High Court of Australia Mason C.J. Mason C.J. Wilson, Brennan, Deane, Dawson, Toohey and Gaudron JJ. Richardson v Forestry Commission (88/007) [1988] HCA 10 ORDER Order that until the hearing and determination of this action, or further order, each defendant by itself, its servants or agents, be restrained from doing any of the following acts during the interim protection period as defined in the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth, namely: (a) for the purposes of, or in the course of carrying out, forestry operations, killing, cutting down or damaging any tree in, or removing any tree or part of a tree from, the area defined in the said Act as the protected area; or (b) constructing or establishing any road or vehicular track within the said protected area, except with the consent in writing of the plaintiff given pursuant to the Act. That until the hearing and determination of this action, or further order, the first-named defendant by itself, its servants or agents be restrained from doing any of the following acts during the said interim protection period, namely, permitting, authorizing, directing or ordering or purporting to permit, authorize, direct or order any person to do any act referred to in sub-pars. 1(a) or 1(b) hereof, except with the consent in writing of the plaintiff given pursuant to the said Act. And it is further ordered that the costs of this application be the plaintiff's costs in the action. Answer the questions as follows: 1. Q. To what extent, if any, is the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 (Cth) invalid? A. The Act is valid. 2. Q. In point of law is any, and if so, which, of the allegations made: (i) in par. 17 of the defence of the first defendant (ii) in par. 15 of the defence of the second defendant (iii) in par. 16 of the defence of the second defendant, an answer to the relief claimed by the plaintiff against the respective defendants? A. (i) Paragraph 17 of the defence of the first defendant is not an answer to the relief claimed. (ii) Paragraph 15(b) of the defence of the second defendant is not an answer to the relief claimed. (iii) Not answered. Order that the defendants pay the plaintiff's costs of the hearing and determination of the questions reserved for the consideration of the Full Court. Cur. adv. vult. 1987, Sept. 3 Mason C.J. delivered the following written judgment:— This is an application for an interlocutory injunction restraining the defendants in the action from doing certain acts alleged to be unlawful under the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act"). The Act provides for the establishment of a Commission of Inquiry into the Lemonthyme and Southern Forests which are situated in fairly close proximity to and to the east of the World Heritage Area in Tasmania. The Act seeks to give effect to Australia's obligations under the Convention for the Protection of the World Cultural and Natural Heritage which is set out in the Schedule to the World Heritage Properties Conservation Act 1983 Cth. Articles 3 and 4 of that Convention provide: 3. It is for each State Party to this Convention to identify and delineate the different properties situated on its territory mentioned in articles 1 and 2 above. 4. Each State Party to this Convention recognizes that the duty of ensuring the identification, protection, conservation, presentation and transmission to future generations of the cultural and natural heritage referred to in Articles 1 and 2 and situated in its territory, belongs primarily to that State. It will do all it can to this end, to the utmost of its own resources and, where appropriate, with any international assistance and co-operation Article 5 provides: To ensure that effective and active measures are taken for the protection, conservation and presentation of the cultural and natural heritage situated on its territory, each State Party to this Convention shall endeavour, in so far as possible, and as appropriate for each country: (d) to take the appropriate legal, scientific, technical, administrative and financial measures necessary for the identification, protection, conservation, presentation and rehabilitation of this heritage The "cultural heritage" as defined by Art. 1 includes under the heading "monuments": "elements or structures of an archaeological nature, inscriptions, cave dwellings and combinations of features, which are of outstanding universal value from the point of view of history, art or science." The "cultural heritage" as so defined also includes under the heading "sites": "works of man or the combined works of nature and man, and areas including archaeological sites which are of outstanding universal value from the historical, aesthetic, ethnological or anthropological points of view." The "natural heritage" as defined by Art. 2 embraces natural features consisting of: physical and biological formations or groups of such formations, which are of outstanding universal value from the aesthetic or scientific point of view; geological and physiographical formations and precisely delineated areas which constitute the habitat of threatened species of animals and plants of outstanding universal value from the point of view of science or conservation; natural sites or precisely delineated natural areas of outstanding universal value from the point of view of science, conservation or natural beauty. Section 4 of the Act states that the: object of this Act is to provide for measures that will enable effect to be given, in relation to the Lemonthyme area and the Southern Forests area, to Australia's obligations under the Convention, in particular the obligations to: (a) identify and delineate the natural heritage and cultural heritage; and (b) take appropriate measures to protect and conserve that heritage. With this object in view, s. 7(1) provides for the appointment of the Commission of Inquiry as soon as practicable after the commencement of the Act, which occurred on 8 May 1987. The Commission has been appointed and is now conducting its inquiry. The Commission is required to report the results of its inquiry to the Minister for the Environment and the Arts before the end of the inquiry period (s. 8(4)) which is the period ending one year after 8 May 1987: s. 3. As a preliminary to understanding the scope of the inquiry to be undertaken by the Commission, it is necessary to look at the definition of the expression qualifying area in s. 3. It is defined to mean: so much of any area that is: (a) wholly or partly within the Lemonthyme area or the Southern Forests area; and (b) and world heritage area or an area that contributes to the integrity or values of: (i) a world heritage area that is wholly or partly within the Lemonthyme area or the Southern Forests area; or (ii) a nominated world heritage area; as is not a nominated world heritage area. The expression "world heritage area" is defined to mean "an area that forms part of the cultural heritage or the natural heritage". The principal matters into which the Commission is required to report are (s. 8(1)(a) and (b)) (a) whether there are any qualifying areas; (b) where there are qualifying areas: (i) whether there are, within Tasmania outside the qualifying areas and national estate areas, alternative forestry resources capable of exploitation without detriment to the Tasmanian forestry industry, and which it would be environmentally and economically prudent and feasible to exploit; (ii) where there are not — whether there are within Tasmania (including national estate areas other than nominated world heritage areas) outside the qualifying areas, alternative forestry resources capable of exploitation without detriment to the Tasmanian forestry industry; and (iii) where there are not — which of the means of exploiting the forestry resources of Tasmania (including the qualifying areas but not including any nominated world heritage areas) without causing any detriment to the Tasmanian forestry industry will cause least damage to the qualifying areas. There are other related matters into which the Commission is required to inquire: s. 8(1)(c), (d) and (e). The Commission is directed to give priority to identifying any part or parts of the Lemonthyme area and the Southern Forests area that are definitely not qualifying areas and to report to the Minister as soon as practicable the identification of any such part or parts, specifying the area concerned: s. 8(5). Part III of the Act deals with the interim protection of the protected area which is defined by s. 3 to mean the Lemonthyme area and the Southern Forests area other than any part that is an excluded area. Section 16 provides: (1) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, to do any of the following acts during the interim protection period: (a) for the purposes of, or in the course of carrying out, forestry operations, to kill, cut down or damage a tree in, or remove a tree or a part of a tree from, the protected area; (b) to construct or establish a road or vehicular track within the protected area; (c) to carry out any excavation works within the protected area; (d) to do any other act prescribed for the purposes of this paragraph, being an act capable of adversely affecting the protected area. (2) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, during the interim protection period to permit, authorise, direct or order or to purport to permit, authorise, direct or order any person to do an act that is unlawful under subsection (1). (3) Except with the consent of the Minister, it is unlawful for a person who is the owner or occupier of any part of the protected area to fail to take reasonable steps to prevent the doing within that part of the protected area of any act that is unlawful under subsection (1). The "interim protection period" is so defined by s. 3 that it commenced on 8 May 1987, the date the Act came into operation, and will continue until 19 June 1988, unless in the meantime notice of receipt by the Minister of the Commission's final report is published in the Commonwealth of Australia Gazette. The Act confers jurisdiction on the High Court or the Federal Court to grant an injunction to restrain a person from doing an act that is unlawful under s. 16: s. 17(1). The jurisdiction extends to granting an interim injunction: s. 17(2). An injunction may be granted (a) whether or not it appears to the Court that the person intends to do again, or to continue to do, an act of that kind; (b) whether or not the person has previously done an act of that kind; or (c) whether or not there is an imminent danger of damage to the protected area if the person does an act of that kind: s. 17(3). The Act confers a right to statutory compensation. Section 19(1) provides: Where: (a) a person refrains from doing an act, being an act of a kind made unlawful by subsection 16(1), by reason only that: (i) the act is made unlawful by that subsection; or (ii) an injunction or interim injunction is granted under section 17 restraining the person from doing the act; and (b) because the person refrains from doing the act, the person suffers loss or damage; the Commonwealth is liable to pay compensation to the person in respect of the loss or damage. Compensation is payable in other circumstances as well: s. 19(2) and (3). Failing agreement compensation is to be determined by the Federal Court: s. 19(4). The plaintiff commenced an action in this Court against the Forestry Commission, which is the statutory authority under the Forestry Act 1920 Tas. having control and management of forest policy and State forest timber in Tasmania, and Gunns Kilndried Timber Industries Ltd. ("Gunns"), a company which carries on business as a harvester and miller of timber in Tasmania. By its amended statement of claim the plaintiff alleges that the Forestry Commission and Gunns have each done acts, during the interim protection period, which are unlawful under s. 16 of the Act in the protected area and that each of them will continue to do so unless restrained by injunction. The plaintiff seeks injunctions restraining each defendant from doing such acts during the interim protection period. Each defendant has demurred to the amended statement of claim on the ground that the Act, in particular Pt III, is ultra vires. By its defence the Forestry Commission has pleaded that no part of the protected area is or could, on any reasonable view of the facts, be part of the natural and cultural heritage (par. 10), alternatively that any such part of the protected area is no more than 2,000 ha. and is easily defined and separate from the remaining part of the protected area (par. 11), and that accordingly the Convention creates no obligations with respect to the protected area or, alternatively, obligations with respect to the area of not more than 2,000 ha.: par. 12. The Forestry Commission also pleads that the protected area is subject to rights, titles and interests which are property rights within the meaning of Art. 6 of the Convention and are excluded from the operation of the Convention by that Article (pars. 14 and 15) and that the relief claimed is not appropriate in the circumstances: par. 17. The defence also puts in issue the substantive allegations in the amended statement of claim. By its defence Gunns admits that it has done acts without the Minister's consent which the plaintiff claims to be unlawful under s. 16, but otherwise puts in issue the substantive allegations in the amended statement of claim. Gunns pleads the property rights exclusion in Art. 6 of the Convention: par. 5(d). Gunns also pleads that the Act was not enacted for the purpose of giving effect to the Convention (par. 15(a)), that the plaintiff made an unambiguous promise or assurance intended to affect the legal relations of the parties on which Gunns acted to its detriment (par. 15(b)), that the plaintiff was guilty of inordinate delay in having the Act enacted thereby causing Gunns to believe that the plaintiff did not intend to make the claim asserted in this action whereby Gunns acted to its detriment (par. 15(c)), that the consequences of granting the relief would inflict damage on Gunns out of all proportion to the relief the plaintiff ought to obtain (par. 15(d)), as well as considerable hardship (par. 15(e)), and that the relief is contrary to the public interest: par. 15(f). Gunns finally pleads that the plaintiff has waived its claim to relief and it would be inequitable to grant it: par. 16. I have reserved for the consideration of the Full Court the following questions: 1. To what extent, if any, is the Act invalid? 2. Is any, and if so, which of the allegations made: (i) in par. 17 of the defence of the Forestry Commission; (ii) in par. 15 of the defence of Gunns; (iii) in par. 16 of the defence of Gunns; are an answer to the relief claimed by the plaintiff? The plaintiff now seeks the following interim orders: 1. That until the hearing and determination of this action, or further order, each defendant by itself, its servants or agents, be restrained from doing any of the following acts during the interim protection period as defined in the Act, namely: (a) for the purposes of, or in the course of carrying out, forestry operations, killing, cutting down or damaging any tree in, or removing any tree or part of a tree from, the area defined in the said Act as the protected area; or (b) constructing or establishing any road or vehicular track within the said protected area, except with the consent in writing of the plaintiff given pursuant to the Act. 2. That until the hearing and determination of this action, or further order, the first-named defendant by itself, its servants or agents be restrained from doing any of the following acts during the said interim protection period, namely, permitting, authorizing, directing or ordering or purporting to permit, authorize, direct or order any person to do any act referred to in sub-pars 1(a) or 1(b) hereof, except with the consent in writing of the plaintiff given pursuant to the said Act. According to the evidence given by Mr. Skuja, the Chief Commissioner of Forests for Tasmania, the Lemonthyme part of the protected area consists of 14,300 ha. approximately and the Southern Forests part 269,000 ha. approximately. Together they represent about 4.5 per cent of Tasmania's land surface. To the west of the protected area lie the Western Tasmanian Wilderness National Parks, covering 698,200 ha. In 1983 the World Heritage Committee included this area in the World Heritage List. The western boundary of the Lemonthyme area is approximately 50 km. long and is the eastern boundary of the World Heritage Area. The western boundary of the Southern Forests area is approximately 320 km. long and is, for 220 km. of its length, the eastern boundary of the World Heritage Area. The northern portion of the Southern Forests area is separated from the World Heritage Area, by State forest not within the protected area, Lake Gordon and the South West Conservation Area. The protected area contains substantial areas of State forest. Twelve per cent of the total area of State forest, amounting to 193,600 ha., lies within the protected area. Forestry Commission management planning has established that only half the forest in the protected area is suitable for commercial exploitation. In the light of past experience 60 per cent only of the areas of State forest identified as suitable for commercial exploitation will be logged, due to inaccessibility and other factors. According to its affidavit evidence, the Forestry Commission will ensure that all forestry operations in the protected area are carried out in accordance with the Forest Practices Code and either a Working Plan or a Management Plan prepared by the Forestry Commission. The Management Plan for the Lemonthyme area took into account submissions from environmental groups and is designed to protect and preserve environmental values. The forestry operations planned for the interim protection period in the Lemonthyme area relate to tree felling of over-mature eucalyptus in three coupes totalling 145 ha. as well as certain road-works. In coupe LA45 (45 ha.), though some felling remains to be carried out, felling has been largely completed. The removal of logs already cut will take place, its seems, by agreement between the parties. Coupe LA49 (35 ha.) is uncut. Coupe GA120B (65 ha.) has been previously cut over and is scheduled for selective logging. Mr. Skuja says that forestry planning in LA45 and 49 included visual management planning as well as botanical and archaeological surveys, directed to the preservation of any outstanding values the area may possess. No like surveys were undertaken for GA120B because it had been previously cut over. Mr. Skuja says that the stands of timber to be logged are not of outstanding botanical value and that the logging will not affect any archaeological sites, flora having outstanding value or world heritage areas. Stands of Eucalyptus simulans on the Forth River, having outstanding botanical value, have been reserved from logging and will not be affected. Logging plans for the Lemonthyme area in the interim protection period, if carried out, would yield 6,900 cubic metres of sawlogs and 20,700 tonnes of pulpwood, having an estimated total value of $2,750,000. Three coupes to be logged in the Southern Forests area are PC48A (50 ha.), WR9A (36 ha.) and DN10C (65 ha.). PC48A is 8 km. from the World Heritage Area and consists mainly of over-mature eucalyptus. Logging will not affect nearby stands of Huon pine, which are reserved, and archaeological sites at Judd's Cavern which is 8 km. distant. WR9A is low in the Huon Valley, 14 km. distant from the World Heritage Area. It has previously been cut over. DN10C is partly within and partly outside the protected area and is 18.5 km. distant from the World Heritage Area. Logging plans in the Southern Forests area in the interim protection period, if carried out, would yield 8,230 cubic metres of sawlogs, 1,400 cubic metres of veneer logs and 53,190 tonnes of pulpwood, having a total ex-mill value of approximately $5,800,000. Planned road-works in the Lemonthyme area would involve clearing for and construction of a logging road from LA49 for a distance of 5.5 km. through over-mature eucalyptus having commercial value only. Planned road-works in the Southern Forests area in the period relates to coupes UC10, WE3, JB4, SN21 and DN10C. In UC10 the road-work is 28 km. distant from the World Heritage Area and is 2 km. in length. The making of the road will involve felling Eucalyptus regnans, an ecologically significant timber in short supply, and it is possible that additional selective logging of this species will be carried out. Mr. Skuja asserts that there are adequate representative stands of this species elsewhere in State forests. WE3 is 14 km. distant from the World Heritage Area. Road-work planned is 2.4 km. in length giving access to old-growth eucalyptus. JB4 is 14 km. from the World Heritage Area. Planned road-work is 3.4 km. in length. The coupe contains re-growth and fire-damaged old-growth eucalyptus, predominantly Eucalyptus regnans. Similar comments apply to SN21 where the planned road-work is 2.4 km. in length. In addition there are road-works planned east of the Picton River, 12 km. distant from the World Heritage Area. The importance of the road-works planned for the summer of 1987-1988 is that they are necessary for the logging in the following summer of the areas to which they give access. Mr. Skuja says that the Forestry Commission's planning does not enable it to make available to the logging industry alternative timber reserves in State forests outside the protected area for logging in the 1987-1988 season. If planned logging operations in the protected area are restrained, this, according to Mr. Skuja, would result in a loss to industry of the total sawlog and veneer log which would have been available from the area. This, he claims, would result in loss of employment in the forest and forest support industries in the Lemonthyme and Southern Forests areas. Gunns plans to extract from LA49 in the 1987-1988 season 3,540 cubic metres of category 1 sawlogs for conversion into sawn timber, apart from completing the logging of LA45. Gunns claims that if it cannot carry out these operations it will suffer a loss of profits of $368,000 and the scaling down of its operation will result in the loss of employment of seven men. Gunns also plans to extract from the three coupes in the Lemonthyme area through the use of contractors, 20,700 tonnes of pulpwood for supply to a company known as A.P.P.M. to be converted into woodchips by that company and supplied to Japanese customers under a continuing agreement. The major proportion of this pulpwood would be lost to A.P.P.M. if operations are restrained, leaving that company unable to perform its contract and damaging its reputation in the eyes of Japanese customers and investors. This, along with the sense of instability arising from government intervention in the Tasmanian timber industry, it is claimed, would have detrimental consequences for the export trade in Tasmanian timber and would endanger forest investment in the industry, notably in a $1 billion export pulpmill planned for Devonport. Australian Newsprint Mills Ltd. ("A.N.M.") and Huon Forest Products Pty. Ltd. are interveners who have commercial logging interests in the Southern Forests area. The interim relief sought by the plaintiff would affect the planned road-work to be carried out in the interim protection period for coupes UC10, WE3, JB4 and SN21, as well as the road-works east of the Picton River and those relating to DN10C, the completion of which is essential for the logging operations which A.N.M. plans for the following season. The grant of relief would result in a valuable loss of leadtime. Huon Forest Products Ltd. would be similarly affected if the Forestry Commission is restrained from undertaking the planned operations for coupes PC43A, PC48A, WR9A, DN10C and, particularly, the road-works east of the Picton River. This intervener has already expended $1,211,214 on preliminary work for a $40 million timber mill at Port Huon. The mill is planned for construction between November 1987 and June 1989. The company will employ 185 persons for forestry operations in the Southern Forests area and eighty in its mill operations. The mill will process pulp woodchips for export from timber logged in concessions in the Southern Forests area. The company's plans call for a throughput of 500,000 tonnes per annum of export chips. Japanese buyers have entered into an agreement in principle to take this amount. If the Forestry Commission's proposed activities described above in the interim protection period are restrained, the company's logging for the following season will be severely disrupted and this may lead to termination of the mill project with consequential loss of the expenditure incurred. The plaintiff's case rests largely on the affidavit of Dr. Kirkpatrick, who is an expert in conservation and plant geography. He identifies in the Southern Forests area four stands of old-growth wet sclerophyll forest (including Eucalyptus regnans) as being of the highest botanical importance. One large stand is in the Picton River Valley. He says there is only one stand of comparable size outside the protected area and that is in the Franklin River region. The four stands of forest should be preserved in their natural state for their intrinsic worth and scientific study. He also identifies a 50 km.2 stand of timber dominated by King Billy pine (found in conjunction with deciduous beech) which, he considers, answers the description of natural heritage in the Convention. He likewise identifies alpine plant communities and an area of Huon pine which also answer this description. He further says that many parts of the protected area can be identified as wilderness having outstanding universal value from the aesthetic point of view and from the point of view of conservation and natural beauty. In identifying all these features he has had regard to the criteria stated in the "Operation Guidelines for the Implementation of the World Heritage Convention" published by the Intergovernmental Committee for the Protection of the World Cultural and Natural Heritage. All the features thus identified by Dr. Kirkpatrick appear to be in the Southern Forests area. He does not identify any world heritage values in the Lemonthyme area except to say that it has wilderness values and abuts the World Heritage Area and is within the viewfield afforded by parts of that area. This is not surprising because he lacks direct field experience in the Lemonthyme area. He then says he considers the Lemonthyme area to be an integral part of the adjacent World Heritage Area and that there are no reasons why that area should terminate on the northern side of the Lemonthyme area as opposed to its southern boundary. However, he goes on to say that forestry works undertaken in the Lemonthyme area have robbed it of any true wilderness character and that it is therefore not a true wilderness buffer but forms part of the immediate viewfield of the World Heritage Area and therefore needs to remain untouched by forestry operations. I am not sure what is the precise effect of Dr. Kirkpatrick's statement about this area. On one view he may be saying that its claim to world heritage values is that it is within a viewfield of the existing World Heritage Area, a claim which for present purposes is not particularly persuasive because the proposed forestry operations, if carried out, would not seem to injure the scenic panorama from the viewing vantage points in the World Heritage Area. On balance I treat Dr. Kirkpatrick as saying that the Lemonthyme area naturally forms part of the World Heritage Area and that it has some wilderness values, despite the fact that its general wilderness character has been adversely affected by forestry works which have already been carried out. This is not to say that the area may not qualify for nomination as a world heritage area, as it may have other natural heritage features or cultural heritage monuments or sites as defined in the Convention which Dr. Kirkpatrick is not in a position to evaluate, not having any direct field experience in the Lemonthyme area. Map overlays exhibited to the affidavit of Mr. Felton, the Commissioner Management of the Forestry Commission, show that there are significant areas of tall eucalypt, some being old-growth taller than 41 metres, in the Lemonthyme area. The plaintiff also relies on an affidavit by Mr. Cosgrove, a professional archaeologist who says that the protected area has the potential to yield archaeological sites of outstanding importance. One such site has been identified: the Warragarra rock shelter in the southern part of the Lemonthyme area. It is distant from the three coupes in the northern part of that area. Mr. Cosgrove mentions another significant archaeological site in the northern part of the Lemonthyme area as well as other sites just outside the Lemonthyme area that have been damaged by forestry operations. He also refers to an important site at the headwaters of the Weld River Valley, 10 km. south of Mt. Mueller in the Southern Forests area. And he makes the point that much more archaeological work needs to be done in the region for there must be many sites of archaeological significance yet to be found. He asserts that all coupes should be examined by a professional archaeologist for possible archaeological significance before any forestry operations proceed. The Forestry Commission admits that damage has been done to archaeological sites in the past before procedures were adopted to protect such sites. A full-time archaeologist is about to be employed jointly by the Forestry Commission and industry to assist with identification and preservation of such sites. The evidence before the Court suggests it is possible that the Lemonthyme area may have features or qualities which would warrant the protection afforded by world heritage listing. This is a matter which the Commission will be in a better position to establish. One problem with Dr. Kirkpatrick's evidence is that he is not specific in terms of stating that a particular surrounding area is to be retained as an area immune from forestry or other development in order to constitute a buffer protection zone for those features identified as having world heritage values as it will vary with each location. He does consider that effective preservation requires that the outstanding features be protected from damage by fire and the introduction of exotic species. He points out that fire is an integral part of Tasmanian forestry operations and that it is carried out in cut-over areas to stimulate regeneration of growth. Such fires occasionally escape. He says that exotic seeds are liable to be introduced by machinery and forest workers after roads are constructed and such seeds will readily take root in soil disturbed by forestry operations. The defendants strongly contest Dr. Kirkpatrick's claims that the risk of damage by fire and the introduction of exotic species is a significant threat. They rely on the affidavit of Mr. Skuja and the affidavit of Mr. Whyte, an Executive Forester for A.P.P.M. Forest Products. They make the point that the prevailing winds are from the north-west or west, i.e., from the World Heritage Area, not from the east where the roads originate, that all forestry fires are carefully managed, having regard to weather and other conditions and that, in the light of the location of the coupes and their distance from the World Heritage Area and the situation of the outstanding features in the protected area identified by Dr. Kirkpatrick, the risk of damage by fire and by the introduction of exotic seeds, if it exists at all, is almost non-existent. Although Mr. Whyte's evidence is impressive, this being an interlocutory application, I am unable to resolve this issue of fact. The affidavit evidence of the deponent is untested by cross-examination. I therefore conclude that there is evidence of some risk of damage, though it may be slight, to the World Heritage Area and to the outstanding features in the protected area, particularly through fire, if the forestry operations planned for the interim protection period go forward. The plaintiff's evidence in this respect is somewhat stronger in relation to the Southern Forests area than to the Lemonthyme area. That there is a serious question to be tried in the action is not in doubt, the serious question being the validity of the Act. The plaintiff's affidavit evidence raises a prima facie case that each of the defendants has done acts without the consent of the Minister in the protection area during the interim protection period, such acts being prohibited by s. 16 of the Act, on the assumption that it is valid. The defendants have not asserted that they will not continue to do such acts if no injunction is granted. The fact that the defendants are not presently carrying on forestry activities in the protected area is entirely due to the fact that winter weather conditions make such operations impossible before September at the earliest. I am therefore satisfied that the defendants intend to continue their activities and to put their forestry plans into operation, if not restrained. In a case such as the present it is somewhat artificial to say that the plaintiff must establish irreparable injury. The plaintiff seeks injunctions to protect the integrity of the area pending the outcome of an inquiry concerning the values or qualities of the area or any part of it as a world heritage area or as a contributor to the integrity or values of a world heritage area. The defendants and the interveners ask me to refuse the injunctions sought on the ground that what they propose to do in the relevant period will not impinge on any such values or qualities that the area or the World Heritage Area may possess. In this respect the defendants and the interveners ask me to pre-judge a portion of that part of the inquiry to which the Commission is directed by s. 8(5) to give priority, i.e., finding that the areas in which the planned activities are to be carried out are not qualifying areas. To put the matter this way may state the point too favourably to the plaintiff in that it is the plaintiff who bears the onus of establishing irreparable injury. It is enough for me to say that on the evidence I conclude that there is a real, as distinct from a bare, possibility that the last-mentioned areas form part of, or contribute to the integrity or values, of a world heritage area and that it is equally possible that the planned activities may adversely affect the integrity or values of a world heritage area. Despite statements that the plaintiff must show that it is probable that the plaintiff will suffer irreparable injury if no injunction is granted (Clements and Marshall Pty. Ltd. v. Field Peas Marketing Board (Tas.) [1] ), in a case such as the present it is enough for the plaintiff to show that irreparable injury is a possibility in the sense stated. The object of the Act being to preserve intact that which may be a unique heritage, the possibility of injury is enough to sustain an interlocutory injunction by way of protecting the area in question, thereby preserving the subject-matter of the inquiry pending its completion at least. 1. (1947) 76 C.L.R. 401, at p. 407. What I have just said conforms to the general principle that, in the absence of compelling grounds, it is the duty of the court to respect, indeed, to defer to the enactment of the legislature until that enactment is adjudged ultra vires: Castlemaine Tooheys Ltd. v. South Australia [2] ; Davids Holdings Pty. Ltd. v. Byrnes [3] . Furthermore, the application of this principle forecloses the issue of balance of inconvenience in favour of the plaintiff. In any event, quite apart from the application of the principle to which I have referred, the balance of convenience favours the plaintiff. Notwithstanding evidence that the defendants and the interveners will suffer substantial loss by reason of the grant of the relief sought and that the injunctions will cause substantial consequential loss to persons engaged in the forestry industry, the timber industry and related activities in Tasmania, the possible loss of, or injury to, what may be a unique heritage must be regarded as the paramount factor. 1. (1986) 60 A.L.J.R. 679; 67 A.L.R. 553. 2. (1987) 71 A.L.R. 251. I am reinforced in reaching this conclusion by the liability to pay compensation which is imposed on the plaintiff by s. 19 and by the statement made by Mr. Black Q.C., during the course of the proceedings on behalf of the plaintiff in these terms: where it is clearly demonstrated to the Commonwealth that a person has suffered loss or damage as a direct result of the cessation of activities; where they would be unlawful or because of an injunction and where that person has made reasonable efforts to mitigate that loss then, in those cases the Commonwealth would provide compensation for that loss. The defendants submit that, despite the conclusions which I have reached, the claim for interlocutory relief should be refused on the ground that the plaintiff has stood by, acquiesced or given ground for supposing that it has consented to the activities sought to be restrained. The defendants rely on the observations in Associated Minerals Consolidated Ltd. v. Wyong Shire Council [4] and Brickworks Ltd. v. Warringah Corporation [5] , to support the proposition that the Court has a discretion in a suit brought to enforce the public interest to refuse an injunction on the ground of acquiescence or misleading conduct. 1. [1975] A.C. 538, at pp. 559-560. 2. (1963) 108 C.L.R. 568, at p. 579. The basis for this submission is that at an earlier time the plaintiff acted inconsistently with the case it now seeks to make. First, the plaintiff did not include the Lemonthyme and Southern Forests area in its nomination to the World Heritage Committee of the existing World Heritage Area. Further, the plaintiff did not nominate the area in question when the Committee invited the plaintiff to include in the World Heritage Area buffer zones. Secondly, the plaintiff made no submission or representation to the Forestry Commission in the course of its seminars and public discussions preparatory to the settlement of the Lemonthyme Management Plan. Again the plaintiff made no submission that the area in question possessed world heritage values when an environmental impact study was made in 1985. Later ministerial statements were made inconsistent with any then claim on the part of the plaintiff that the area possessed such values, culminating in the plaintiff entering into a memorandum of understanding on 12 June 1986 whereby the plaintiff agreed to forestry operations in the area on conditions which are and will be observed in connexion with the defendants' and interveners' proposed activities. Finally the plaintiff allowed the activities which took place during the 1986-1987 season, which I have already described, to go forward without interference. In my view these matters do not constitute a sufficient ground for refusing the relief sought. With the exception of activities at the end of the 1986-1987 season the matters relied on antedate the enactment and commencement of the Act. On the evidence before me the plaintiff's intentions have been clearly manifest from the time of the passing of the Act. There has been no acquiescence, standing by or consent since then and, on the footing that there is a possibility of irremediable injury to the public interest sought to be protected by the Act, antecedent acquiescence or misleading conduct is not an answer to the application for interlocutory relief. It would be in the public interest, and in the interests of the defendants in particular, if the Commission, as a matter of urgency, pursuant to s. 8(5) of the Act, were to give priority to identifying any parts of the protected area, especially in relation to the Lemonthyme area, which are not qualifying areas. In the result I grant injunctions in terms of orders 1 and 2 of the plaintiff's summons. Costs will be the plaintiff's costs in the action. Cur. adv. vult. The following written judgments were delivered:— 1988, March 10 Mason C.J. and Brennan J. Part II (ss. 7-15 inclusive) of the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act") makes provision for the establishment of a Commission of Inquiry into the "protected area", being the Lemonthyme area and the Southern Forests area in Tasmania, other than any part which is excluded (s. 3), with a view to ascertaining, amongst other things, whether any part of the area is, or contributes to, a world heritage area. Part III (ss. 16-19 inclusive) provides for the interim protection of the protected area during the "interim protection period", an expression which is defined in s. 3 by reference to another defined expression, the "inquiry period", to which we shall refer subsequently. In this action the plaintiff, who is the federal Minister for the Environment and the Arts and as such is responsible for the administration of the Act, seeks to enforce the provisions of s. 16(1) and (2) of the Act which prohibit, except with the consent in writing of the plaintiff, the doing of certain acts in the protected area during the interim protection period. The defendants in the action are the Forestry Commission, which is the statutory authority created by the Forestry Act 1920 Tas. having control and management of forest policy and State forest timber in Tasmania, and Gunns Kilndried Timber Industries Ltd., which carries on business as a harvester and miller of timber in Tasmania. On 3 September 1987 Mason C.J. granted interlocutory injunctions restraining the defendants until the hearing and determination of the action from cutting down and removing any tree or constructing any road or vehicular track and from permitting, authorizing, directing or ordering any person to do any such act in the protected area during the interim protection period. The Court is now required to consider two questions which Mason C.J. reserved, on 30 July 1987, for the consideration of the Full Court. The first question is: "To what extent, if any, is the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth invalid?" The parties are agreed that the statement of facts contained in Mason CJ.'s judgment delivered when the interlocutory injunctions were granted, except in so far as it deals with disputed facts, may be referred to for the purpose of determining the question of validity. The plaintiff's case is that the Act is valid as an exercise of the legislative power with respect to external affairs (s. 51(xxix) of the Constitution), being an implementation of the Convention for the Protection of the World Cultural and National Heritage ("the Convention") to which Australia is a party. The Parliament has by the World Heritage Properties Conservation Act 1983 Cth, adopted and given effect to the Convention. The thrust of the defendants' case is that the Act is invalid to the extent to which it prohibits the doing of acts in the protected area during the interim protection period. The defendants submit that ss. 16 and 18 of the Act are beyond power on the ground that they go beyond any legitimate implementation of the Convention. Section 4 states that the "object of this Act is to provide for measures that will enable effect to be given, in relation to the Lemonthyme area and the Southern Forests area, to Australia's obligations under the Convention, in particular the obligations to: (a) identify and delineate the natural heritage and cultural heritage; and (b) take appropriate measures to protect and conserve that heritage". The Lemonthyme and Southern Forests areas are situated in fairly close proximity and to the east of the existing World Heritage Area in western Tasmania, known as the Western Tasmanian Wilderness National Parks, covering 698,200 ha., which in 1983 was included in the World Heritage List maintained pursuant to Art. 11(2) of the Convention. The Lemonthyme area consists of 14,300 ha. approximately and the Southern Forests area 269,000 ha. approximately. Together they represent about 4.5 per cent of Tasmania's land surface. The western boundary of the Lemonthyme area is approximately 50 km. long and is the eastern boundary of the World Heritage Area. The western boundary of the Southern Forests area is approximately 320 km. long and is, for 220 km. of its length, the eastern boundary of the World Heritage Area. The northern portion of the Southern Forests area is separated from the World Heritage Area by State forest not within the protected area, Lake Gordon and the South West Conservation Area. The protected area is largely wilderness in which forestry operations are carried on. A large part of the area is subject to Tasmanian legislation which grants or authorizes the grant of rights and licences for forestry operations. Apart from forestry operations it seems that the only significant activities conducted in the area are grazing operations undertaken on 155 ha. of land in private ownership in the Lemonthyme area and 80 ha. privately owned in the Southern Forests area. Section 7(1) provided for the appointment of the Commission as soon as practicable after the commencement of the Act on 8 May 1987. The Commission has been appointed and is conducting its inquiry. The Commission is required to report the results of its inquiry to the Minister before the end of the inquiry period: s. 8(4). The inquiry period is defined as the period of one year after 8 May 1987: s. 3. The principal matters into which the Commission is required, by s. 8(1)(a) and (b), to report are: (a) whether there are any qualifying areas; (b) where there are qualifying areas: (i) whether there are, within Tasmania outside the qualifying areas and national estate areas, alternative forestry resources capable of exploitation without detriment to the Tasmanian forestry industry, and which it would be environmentally and economically prudent and feasible to exploit; (ii) where there are not — whether there are within Tasmania (including national estate areas other than nominated world heritage areas) outside the qualifying areas, alternative forestry resources capable of exploitation without detriment to the Tasmanian forestry industry; and (iii) where there are not — which of the means of exploiting the forestry resources of Tasmania (including the qualifying areas but not including any nominated world heritage areas) without causing any detriment to the Tasmanian forestry industry will cause least damage to the qualifying areas. There are other related matters into which the Commission is required to inquire: s. 8(1)(c), (d) and (e). The Commission is to give priority to identifying any part or parts of the Lemonthyme and Southern Forests areas that are definitely not qualifying areas and to report to the Minister as soon as practicable the identification of any such part or parts, specifying the area concerned: s. 8(5). The expression "qualifying area" is defined by s. 3 to mean: so much of any area that is: (a) wholly or partly within the Lemonthyme area or the Southern Forests area; and (b) a world heritage area or an area that contributes to the integrity or values of: (i) a world heritage area that is wholly or partly within the Lemonthyme area or the Southern Forests area; or (ii) a nominated world heritage area Section 3 defines a number of expressions which appear in the Act. Thus, "nominated world heritage area" means "any area of Tasmania that the Commonwealth has, under Article 11 of the Convention, submitted to the World Heritage Committee as suitable for inclusion in the World Heritage List ". "World heritage area" means "an area that forms part of the cultural heritage or the natural heritage". The expressions "cultural heritage" and "natural heritage" bear the same meanings as they have in the Convention. At this point it is convenient to refer to the provisions of the Convention. The object of the Convention, as stated by the ninth recital, is to establish "an effective system of collective protection of the cultural and natural heritage of outstanding universal value, organized on a permanent basis and in accordance with modern scientific methods". Articles 3 and 4 of the Convention provide: 3. It is for each State Party to this Convention to identify and delineate the different properties situated on its territory mentioned in Articles 1 and 2 above. 4. Each State Party to this Convention recognizes that the duty of ensuring the identification, protection, conservation, presentation and transmission to future generations of the cultural and natural heritage referred to in Articles 1 and 2 and situated on its territory, belongs primarily to that State. It will do all it can to this end, to the utmost of its own resources and, where appropriate, with any international assistance and co-operation Article 5(d) provides: To ensure that effective and active measures are taken for the protection, conservation and presentation of the cultural and natural heritage situated on its territory, each State Party to this Convention shall endeavour, in so far as possible, and as appropriate for each country: (d) to take the appropriate legal, scientific, technical, administrative and financial measures necessary for the identification, protection, conservation, presentation and rehabilitation of this heritage The "cultural heritage" as defined by Art. 1 includes under the heading "monuments": "elements or structures of an archaeological nature, inscriptions, cave dwellings and combinations of features, which are of outstanding universal value from the point of view of history, art or science". The "cultural heritage" as defined also includes under the heading "sites": "works of man or the combined works of nature and man, and areas including archaeological sites which are of outstanding universal value from the historical, aesthetic, ethnological or anthropological points of view". The "natural heritage" as defined by Art. 2 embraces natural features consisting of: physical and biological formations or groups of such formations, which are of outstanding universal value from the aesthetic or scientific point of view; geological and physiographical formations and precisely delineated areas which constitute the habitat of threatened species of animals and plants of outstanding universal value from the point of view of science or conservation; natural sites or precisely delineated natural areas of outstanding universal value from the point of view of science, conservation or natural beauty. The thrust of these definitions is to emphasize that, in order to constitute part of the world heritage, a property must possess characteristics of outstanding universal value. We use the expressions "world heritage" and "heritage" to signify properties which collectively fall within the cultural and natural heritage as so defined. The defendants do not dispute that inquiry is integral to the process of identification and delineation. Indeed, the defendants acknowledge the validity of Pt II of the Act. The argument is that Pt II goes beyond identification of the world heritage in that it authorizes the Commission to inquire into the forestry industry in Tasmania and the availability of forest resources in the State. This argument may be disposed of quite shortly. The scope of the inquiry which the Commission is undertaking is designed to inform the Executive Government so that it may determine the course which it is to take with respect to the areas in question, having regard to its obligations under the Convention. As will appear hereafter, the Convention permits the State in whose territory part of the world heritage is situated to take into account economic and other factors in deciding how it will discharge the duty imposed upon it by the Convention. Part II authorizes the Commission to inquire into various matters relevant to the Government's making an informed decision as to how it will discharge this duty. What the defendants dispute is the validity of the regime of protection for which Pt III provides. This regime centres on s. 16, which provides: (1) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, to do any of the following acts during the interim protection period: (a) for the purposes of, or in the course of carrying out, forestry operations, to kill, cut down or damage a tree in, or remove a tree or a part of a tree from, the protected area; (b) to construct or establish a road or vehicular track within the protected area; (c) to carry out any excavation works within the protected area; (d) to do any other act prescribed for the purposes of this paragraph, being an act capable of adversely affecting the protected area. (2) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, during the interim protection period to permit, authorise, direct or order or to purport to permit, authorise, direct or order any person to do an act that is unlawful under subsection (1). (3) Except with the consent of the Minister, it is unlawful for a person who is the owner or occupier of any part of the protected area to fail to take reasonable steps to prevent the doing within that part of the protected area of any act that is unlawful under subsection (1). The section needs to be read with the definition of "interim protection period". This expression is defined by s. 3 to mean: the period commencing at the commencement of the inquiry period and ending at the end of the forty-second day after: (a) where paragraph (b) does not apply — the end of the inquiry period; or (b) where, before the last day of the inquiry period, notice of the receipt by the Minister of the final report is published in the Gazette under subparagraph 20(a)(ii) — the day on which that notice is published. Section 16 is linked to s. 18 which provides: (1) In determining whether or not to give a consent under section 16, the Minister shall have regard only to Australia's obligations under the Convention. (2) A consent given by the Minister under section 16 may relate to: (a) a particular act or particular acts or a particular class or particular classes of acts; or (b) a particular person or particular persons or a particular class or particular classes of persons. Jurisdiction is conferred on the High Court or the Federal Court to grant an injunction to restrain the doing of an act that is unlawful under s. 16: s. 17(1). An injunction may be granted (a) whether or not it appears to the court that the person intends to do again, or to continue to do, an act of that kind; (b) whether or not the person has previously done an act of that kind; or (c) whether or not there is an imminent danger of damage to the protected area if the person does an act of that kind: s. 17(3). Section 19(1) confers a right to statutory compensation. The sub-section is in these terms: Where: (a) a person refrains from doing an act, being an act of a kind made unlawful by subsection 16(1), by reason only that: (i) the act is made unlawful by that subsection; or (ii) an injunction or interim injunction is granted under section 17 restraining the person from doing the act; and (b) because the person refrains from doing the act, the person suffers loss or damage; the Commonwealth is liable to pay compensation to the person in respect of the loss or damage. Compensation is payable in other circumstances as well: s. 19(2) and (3). Failing agreement compensation is to be determined by the Federal Court: s. 19(4). The defendants submit that, on its true construction, the Convention does not impose any obligations on Australia with respect to the Lemonthyme and Southern Forests areas before Australia accepts that the land has world heritage values or until the land is entered on the World Heritage List. The defendants read the opening words of Art. 3, "It is for each State to identify and delineate the different properties situated on its territory", not as imposing an obligation, but as asserting that it is the prerogative or the province of the State to take the action described. This view of Art. 3 is, so the argument runs, reinforced by Art. 11(3) which states: "The inclusion of a property in the World Heritage List requires the consent of the State concerned." This submission fails to take sufficient account of the nature of the obligations imposed by the Convention, especially the obligations imposed on each State with respect to the cultural and natural heritage in its territory. In The Commonwealth v. Tasmania ("the Tasmanian Dam Case ") [20] , the Court held that the external affairs power enables the Parliament of the Commonwealth to give effect to the Convention as an international treaty to which Australia is a party. The majority of the Court (Mason, Murphy, Brennan and Deane JJ.) considered that, when Parliament exercises the external affairs power so as to carry into effect or give effect to such a treaty, it is for Parliament to choose the means by which this is to be achieved, provided at any rate that the means chosen are capable of being reasonably considered appropriate and adapted to that end [21] . The majority expressly recognized that the power was not limited to the implementation of obligations imposed on Australia by a treaty which Australia is bound to implement [22] . 1. (1983) 158 C.L.R. 1. 2. (1983) 158 C.L.R., at pp. 130-131, 172, 232, 259. 3. (1983) 158 C.L.R., at pp. 129-130, 171-172, 177, 226, 258-259. However, in that case the Court held that the relevant legislation implemented obligations cast upon Australia by the Convention, thereby rejecting the view put forward by the defendants that Arts. 3, 4 and 5 amounted to no more than a statement of general political accord which left it open to each State to determine its course of action concerning the world heritage. Article 6(1), whilst respecting the sovereignty of the States on whose territory the cultural and natural heritage is situated, and "without prejudice to property rights provided by national legislation", makes the point that "such heritage constitutes a world heritage for whose protection it is the duty of the international community as a whole to co-operate" (our emphasis). Within the framework of this general duty the Convention imposes particular duties on each State with respect to the world heritage on its territory. Thus Art. 4 involves each State in acknowledging that the duty of ensuring the identification, protection, conservation and presentation of the world heritage situated on its territory belongs primarily to that State. And Art. 5, with a view to ensuring the protection, conservation and presentation of the heritage, requires each State to take appropriate legal and other measures necessary to bring this about, making specific mention in par. (d) of the identification of the heritage. Viewed in this setting, Art. 3 does not qualify the duty imposed on each State with respect to the heritage on its territory. Rather it reinforces the imposition of that duty by making it plain that in the matter of identification and delineation the obligation rests exclusively, not primarily, with that State. The terms of Art. 3, together with the second sentence of Art. 4 and the qualifications in the opening words of Art. 5 are entirely consistent with the acknowledgment of State sovereignty in Art. 6 and with the recognition that each State, in giving effect to the obligations imposed by the Convention, with respect to the heritage situated on its territory will naturally have to take account of competing considerations, economic and otherwise. Thus though each State has a duty to identify and delineate the heritage in its territory, the performance of this duty will depend in many respects on the judgment of that State. The reservation with respect to property rights is designed to ensure that the operation of the Convention does not in itself derogate from property rights under national laws, especially in countries where adherence automatically results in the Convention becoming part of the law of the land. What we have said so far is not necessarily fatal to the defendants' principal submission that there is no obligation to protect a particular property unless and until Australia identifies and delineates it as part of the heritage. But it is significant, as the ninth recital and the opening words of Art. 5 so clearly indicate, that the object of the Convention is to protect that heritage. In this setting identification is not an obligation independent and distinct from the obligation to ensure protection. Identification is an element in the duty to ensure protection, though the responsibility to identify rests solely with the particular State. Identification and for that matter delineation contribute to the attainment of the ultimate object which is protection of the heritage; indeed, they are the means of achieving that object. So interpreted, the Convention does not sustain the view that the duty to ensure protection does not arise or attach to land until the State identifies and delineates that land as part of the heritage. This is not to say that a failure on the part of a State to protect land, which is ultimately identified as part of the heritage, pending that identification is a breach of duty capable of enforcement. It is for each State to determine what it will do by way of protecting a particular property pending resolution of its status as part of the heritage. But the taking of action by a State to protect or conserve a particular property in its territory pending resolution of the status of that property as part of the heritage is to carry out and give effect to the Convention because the taking of the action is incidental to the State's duty to ensure protection of the heritage and to the attainment of the object of the Convention. Granted ultimate identification of the property as part of the heritage, the absence of such action by way of interim protection in the meantime would expose the property to the possibility of irreparable damage. The taking of action by way of interim protection pursuant to the external affairs power, e.g., by the enactment of legislation prohibiting destruction of, or damage to, particular property, pending a determination of its status as a property to be nominated for inclusion in the World Heritage List may be supported as action which can reasonably be considered appropriate and adapted to the attainment of the object of the Convention, namely the protection of the heritage. However, the defendants challenge the legitimacy of this action on the footing that there is no basis, or no reasonable basis, for concluding that the land in question might constitute part of the heritage. Whether there is such a basis in the present case is a question which we leave for later consideration because it is convenient now to deal with other aspects of the defendants' challenge to Pt III of the Act. The defendants submit that the legislative scheme in Pt III is not in conformity with Australia's obligations under the Convention or lacks the necessary proportionality to those obligations. They point to that part of the decision in the Tasmanian Dam Case whereby it was declared that s. 9(1)(a) to (g) of the World Heritage Properties Conservation Act was invalid and particularly to the reasons given by Brennan and Deane JJ. for reaching that conclusion. According to their Honours, those provisions generally prohibited the kinds of acts therein specified whenever done on any property to which the prohibitions were expressed to apply. As it was impossible to conclude that these prohibitions, in their application to all such properties at all times, would contribute to the protection and conservation of those properties, the provisions were too wide. They were not saved by the limitation placed by s. 13 on the Minister's discretion to grant or refuse written consent to the doing of an act otherwise prohibited. Section 13 did not restrict the operation of the provisions to a faithful pursuit of the objects of the Convention. In this respect there was a lack of reasonable proportionality between the provisions of s. 9(1)(a) to (g) and the purpose of protecting and conserving the relevant property: see the Tasmanian Dam Case [23] . 1. (1983) 158 C.L.R., at pp. 236-237, 266-267. The defendants make a similar attack on ss. 16 and 18. They make the point that s. 16(1)(a) is directed against forestry operations rather than damage howsoever caused. No doubt this aspect of s. 16 is explicable by reference to the fact that forestry operations present the principal possibility of damage to the character of the area in question — a consideration which tells in favour of, not against, validity — and to the circumstance that the area is the subject of existing State legislative regulation. The Forestry Act 1920 Tas. prohibits the cutting and removal of timber in State forests otherwise than in accordance with that Act. And, as already mentioned, a large part of the area is, or may be made, the subject of statutory rights or licences for forestry operations. No doubt some of the acts prohibited by s. 16(1)(a), (b) and (c) may be so trivial that they do not present a significant risk of real impairment to the world heritage characteristics of the land in question. None the less the class of acts prohibited, namely tree-felling and removal in the course of forestry operation, road and track construction and excavation, are generally speaking acts involving a potential risk of injury to any qualifying areas which may be in the Lemonthyme and Southern Forests areas. It is therefore appropriate to single them out as objects of prohibition unless the plaintiff consents in writing to them. We should have thought that only by such a means of regulation is it possible to ensure protection of the land in conformity with the Convention. But it is not necessary to go so far. It is enough to say that, subject to the question which we have reserved for later consideration, the provisions are a means for effectuating a desired end which is within power, namely ensuring protection of land which may be identified as part of the world heritage. We refer to the remarks of Kitto J. in Herald and Weekly Times Ltd. v. The Commonwealth [24] . 1. (1966) 115 C.L.R. 418, at p. 437. The prohibition in s. 16(1)(a) affects forestry operations planned in the interim protection period covering an area of 145 ha. in the Lemonthyme area and 151 ha. in the Southern Forests area, together with road-works associated with planned logging operations. The prohibition contained in s. 16(1)(a) would have no application to grazing activities. The remaining prohibitions in s. 16(1)(b) are capable of applying to acts done in the course of such activities subject of course to the plaintiff's power to consent. The defendants submit that the exercise of the power to grant or refuse consent in writing under s. 18 is not reviewable. The ambit of the discretion is limited by sub-s. (1), which requires the plaintiff to "have regard only to Australia's obligations under the Convention". Nevertheless the defendants contend that, on its true construction, s. 18 makes the plaintiff's opinion the decisive consideration. If the section is so framed that the relationship between the act for which consent is sought and the attainment of the object of the Convention would depend on the opinion of the plaintiff as to fact or law, the section cannot be upheld: Hughes and Vale Pty. Ltd. v. New South Wales [No. 2] [25] ; MacCormick v. Federal Commissioner of Taxation [26] . That is not how we read the sub-section. It should be understood as disentitling the plaintiff to refuse consent except when refusal is necessary for the protection of the heritage or otherwise for the satisfaction of Australia's obligations under the Convention: see Art. 5(d). The plaintiff must form an opinion in order to make his decision. So to read the sub-section is consistent both with its plain meaning and with the principle of interpretation which requires a statute to be read in such a way that will preserve its validity. As Dixon J. observed in Attorney-General (Vict.) v. The Commonwealth ("the Pharmaceutical Benefits Case") [27] : In discharging our duty of passing upon the validity of an enactment, we should make every reasonable intendment in its favour. We should give to the powers conferred upon the Parliament as ample an application as the expressed intention and the recognized implications of the Constitution will allow. We should interpret the enactment, so far as its language permits, so as to bring it within the application of those powers and we should not, unless the intention is clear, read it as exceeding them. (Our emphasis.) Construed in this way, s. 18 merely empowers the plaintiff to refuse consent when refusal to relax the statutory prohibition against the doing of the proposed act is necessary to the attainment of the object of the Convention. The section does not enable the plaintiff to refuse consent on general environmental grounds, e.g., in order to preserve the wilderness characteristics of an area, as distinct from the world heritage characteristics of that area, that is characteristics having outstanding universal value within the meaning of the definitions in Arts. 1 and 2 of the Convention. The Minister's decision will be subject to review under the Administrative Decisions (Judicial Review) Act 1977 Cth and under the general law, for example, by way of prerogative writ or declaratory relief. 1. (1955) 93 C.L.R. 127, at pp. 165-166. 2. (1984) 158 C.L.R. 622, at pp. 639-640, 658. 3. (1945) 71 C.L.R. 237, at p. 267. The defendants then submit that Pt III violates the implied prohibition upon discrimination against a State. The argument is that a law which singles out for protection a particular area of a particular State in purported pursuance of an international obligation applying to the whole of Australia, in the absence of any special threat to that particular area is a discrimination against that State. It is pointed out that no such regime as Pt III protects other parts of Australia which are said to be under threat, notably areas of rainforest in Queensland. The short answer to this submission is that the defendants have not established any foundation for a case of invalid discrimination in the sense of a differential treatment of Tasmania which is not occasioned by the subject to which the law relates. The obligation of protection necessarily falls to be discharged with respect to particular properties and a law which is calculated merely to discharge Australia's treaty obligations with respect to a particular property does not invalidly discriminate against the State in whose territory the property is situated. In any event, there is no evidence to suggest that there are areas in other States which have equal or stronger claims to protection under the Convention. In relation to validity it remains for us to consider the defendants' submission that there is no sufficient basis for concluding that the area has potential world heritage characteristics and for subjecting the entirety of the protected area to the regime of protection during the interim protection period. It has been said that the Court must be satisfied of every fact the existence of which is necessary in law to provide a constitutional basis for legislation: Australian Communist Party v. The Commonwealth [28] ; Hughes and Vale [No. 2] [29] ; Commonwealth Freighters Pty. Ltd. v. Sneddon [30] , notwithstanding that it is "[h]ighly inconvenient" for the Court to be engaged in making factual inquiries, as Dixon C.J. noted in Commonwealth Freighters [31] and Breen v. Sneddon [32] . 1. (1951) 83 C.L.R. 1, at p. 222. 2. (1955) 93 C.L.R., at p. 165. 3. (1959) 102 C.L.R. 280, at p. 307. 4. (1959) 102 C.L.R., at p. 292. 5. (1961) 106 C.L.R. 406, at p. 411. Here, however, we are not concerned with the making of a conclusive finding of constitutional facts necessary to support the exercise of a legislative power with respect to a head of power. Rather we are concerned to ascertain whether there is a basis for invalidating the legislative judgment that the area in question may possess world heritage characteristics which justify on an interim footing the freeze on activities for which Pt III provides. The defendants' case challenging the legislative judgment rests largely on the fact that Pt III of the Act imposes a freeze on an area constituting 4.5 per cent of Tasmania's land surface, there being an absence of findings or evidence to justify a conclusion that the whole of the area, as distinct from particular locations within it, possesses or may possess world heritage characteristics. Mason CJ.'s judgment on the interlocutory application sets out what is known of the area in terms of characteristics that may be relevant to world heritage values. Broadly speaking, that evidence indicates that there are particular stands of rare timber, aboriginal cave dwellings and archaeological sites. It also indicates that the area, especially the Southern Forests area, which is less well known, may possess important world heritage characteristics, particularly cave dwellings and archaeological sites, as yet unidentified. The fact is that the area in general has not yet been closely examined with a view to determining its eligibility for entry on the World Heritage List, this being the reason for establishing the present inquiry and imposing the freeze during the interim protection period. Moreover, in identifying and delineating any property as part of the world heritage it is necessary to allow for the protection of an adequate "buffer zone". Paragraph 14 of the World Heritage Committee's Operational Guidelines for the Implementation of the World Heritage Convention defines a "buffer zone" as "an area surrounding the property which has an essential influence on the physical state of the property and/or on the way in which the property is perceived". The plaintiff's case is that the delineation of any relevant part of the area will involve the identification of a buffer zone, not only in relation to world heritage characteristics of the area, but also in relation to the existing world heritage area. The plaintiff claims that in identifying the buffer zone it is necessary to take account of the need to protect world heritage characteristics from the added risks of fire and the introduction of exotic flora which may result from commercial operations in the area. How real these risks are may be a matter of conjecture. Paragraph 14 also makes the point that "the area constituting the buffer zone should be determined in each case through technical studies". The Guidelines recognise that the identification and delineation of a property require investigation, including technical studies, and this inevitably takes time. The matters to which we have referred provide a basis for a legislative judgment that substantial parts of the area, the location of which cannot be identified at this time with any certainty, may conceivably possess world heritage characteristics which should be protected. If part of an area might possess world heritage characteristics and if that part might be damaged unless the area is protected by legislative measures appropriate to preserve that part, a failure to take those measures involves a risk that the Convention obligation will not be discharged. It is only by taking those measures that the risk of failing to discharge the Convention obligation can be avoided. As the external affairs power is a plenary power, it extends to support a law calculated to discharge not only Australia's known obligations but also Australia's reasonably apprehended obligations. The power extends to support a law required to discharge a treaty obligation which is known to exist and also a law which is required to ensure the discharge of a treaty obligation which is reasonably apprehended to exist. In making provision for the establishment of the Commission of Inquiry and for the regime of interim protection of the protected area, Parliament has made a legislative judgment about the situation and the Convention obligation that may be proved to exist. It is not for us to impugn the bona fides of that judgment. It is enough that the legislative judgment could reasonably be made or that there is a reasonable basis for making it. Particularly is this so when the ultimate decision to be made by the Executive Government, whether the area, or parts of it, should be proposed for inclusion in the World Heritage List, involves a calculus of factors, including factors which are cultural, economic and political. Of course, if the legislative judgment cannot reasonably be supported, the Court will not hesitate to declare that it is invalid as an excess or abuse of power: see Gerhardy v. Brown [33] . 1. (1985) 159 C.L.R. 70, at p. 139. Consequently we would answer the first question by declaring that the Act is valid in its entirety. The second question which Mason C.J. reserved for the consideration of the Full Court is: In point of law is any, and if so, which, of the allegations made: (i) in par. 17 of the Defence of the First Defendant (ii) in par. 15 of the Defence of the Second Defendant (iii) in par. 16 of the Defence of the Second Defendant, an answer to the relief claimed by the plaintiff against the respective defendants? Paragraph 17 of the defence of the first defendant pleads: "The relief claimed against it is not appropriate relief in all the circumstances." The first defendant furnished particulars of par. 17 of which the first defendant now relies only on the following: The First Defendant further says that the granting of relief claimed is inappropriate in that it will, in the manner sought, cause economic hardship to the First Defendant and to the economy of the State of Tasmania generally, whereby it would be contrary to the public interest. The second defendant now relies only on par. 15(b), (d), (e) and (f) of its defence. Paragraph 15(b) pleads the making by the Commonwealth of an unambiguous promise or assurance which was intended to affect the legal relations between the parties and the second defendant and has acted upon the promise or assurance, thereby altering its position to its detriment. Paragraphs 15(d), (e) and (f) plead matters similar to the matters pleaded in par. 17 of the defence of the first defendant. The defendants submit that the determination of the second question reserved should be left to the trial judge on the footing that the defences pleaded are discretionary defences. The plaintiff opposes this course on the ground that under s. 17 a court, in deciding whether or not to grant an injunction, cannot take account of the matters pleaded on a discretionary basis. The matters pleaded in par. 17 of the first defendant's defence cannot constitute a defence to the action. As to par. 15(b) of the second defendant's defence, it is not claimed that the promise or assurance was given after the Act came into operation. And in any event the giving of the promise or assurance could not amount to a defence. It is not easy to envisage situations in which the second defendant's discretionary defences (pleaded in par. 15(d), (e) and (f)) will be an effective answer to the action. None the less there is the difficulty of dealing with the matter in the abstract in the absence of agreed facts. In these circumstances we would not answer the question so far as it relates to these paragraphs. In the result we would answer the questions reserved as follows: 1. The Act is valid. 2. (i) Paragraph 17 of the defence of the first defendant is not an answer to the relief claimed. (ii) Paragraph 15(b) of the defence of the second defendant is not an answer to the relief claimed. (iii) Not answered. Wilson J. In this matter, the Chief Justice has reserved two questions for the consideration of the Full Court. The first asks to what extent, if any, is the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act") invalid? The second question involves discretionary considerations relating to injunctive relief. The defendants requested that those matters be left for determination by a single justice in the event of the case proceeding to hearing for the grant of a final injunction. In consequence of that request the Court did not hear full argument on the question. Nevertheless, I agree that it should be dealt with in the manner proposed by the Chief Justice and Brennan J. The object of the Act is described in s. 4 as follows: The object of this Act is to provide for measures that will enable effect to be given, in relation to the Lemonthyme area and the Southern Forests area, to Australia's obligations under the Convention, in particular the obligations to: (a) identify and delineate the natural heritage and cultural heritage; and (b) take appropriate measures to protect and conserve that heritage. The material provisions of the Act and a description of the circumstances leading to its enactment are contained in the reasons for judgment prepared by the Chief Justice and Brennan J. and it is unnecessary to repeat them in their entirety. The reference in s. 4 to "the Convention" is a reference to the Convention for the Protection of the World Cultural and Natural Heritage, the same Convention as was considered by this Court in The Commonwealth v. Tasmania ("the Tasmanian Dam Case ") [34] . So far as is material, the crucial questions in that case were whether in the relevant respect the Convention imposed any obligations upon Australia and, if so, whether those obligations were of such a character as to be capable of attracting the power of the Commonwealth Parliament to legislate for the peace, order and good government of the Commonwealth with respect to external affairs: Constitution, s. 51(xxix). The Court, by majority (Mason, Murphy, Brennan and Deane JJ., Gibbs CJ., Wilson and Dawson JJ. dissenting), resolved each question in the affirmative. In substance, the view of the minority justices was that the Convention in the relevant respect was of a hortatory nature which fell short of imposing binding obligations upon Australia with respect to the cultural and natural heritage ("the world heritage") situated within its territory, but that in any event the power to legislate with respect to external affairs did not extend to the enactment of a law having only a domestic operation within Australia upon a topic lacking an international character. On the other hand, the majority decided that the Convention imposed binding obligations upon Australia with respect to the heritage within its bounds and that a law discharging those obligations was a law with respect to external affairs. Although I remain convinced of the correctness of the view I expressed in the Tasmanian Dam Case — and indeed the argument in the present case has served only to strengthen that sense of conviction — unless and until the decision is reviewed I am obliged to accept its authority. Unfortunately, this must be so, despite the serious implications that flow from the expansive interpretation of the power to legislate with respect to external affairs, an interpretation which in my opinion proceeds without regard to the context of par. (xxix) in s. 51 and to the federal character of the Constitution. The wider interpretation is not one which has the support of any binding authority to be found in any decision of this Court prior to the Tasmanian Dam Case. I have referred to the serious implications of such an interpretation in Koowarta v. Bjelke-Petersen [35] and in the Tasmanian Dam Case [36] . There is no point in repeating what I then wrote. The present case must be approached on the basis that the Tasmanian Dam Case established both the existence of certain obligations imposed upon Australia by the Convention and the legislative power of the Commonwealth with respect to their observance. Nevertheless, consideration will need to be given both to the precise scope of the relevant obligation and to the scope of the legislative power which is attracted by reason of it. 1. (1983) 158 C.L.R. 1. 2. (1982) 153 C.L.R. 168, at pp. 251-252. 3. (1983) 158 C.L.R., at pp. 196-198. The striking feature which serves to distinguish the facts of the present case from those of the Tasmanian Dam Case is that no provision of the Act applies to any area which is known to form part of the world heritage. There is no suggestion that the provisions of the World Heritage Properties Conservation Act 1983 Cth, which apply to property forming part of the world heritage, have any application. Indeed, the primary task of the Commission of Inquiry into the Lemonthyme and Southern Forests ("the Commission") established by the Act is to inquire into and report whether there are any qualifying areas: s. 8(1)(a). A "qualifying area" is defined to mean, in substance, so much of any area that is (a) wholly or partly within the Lemonthyme area or the Southern Forests area, and (b) is a world heritage area or an area that contributes to the integrity or values of a world heritage area: s. 3. Part III of the Act deals with the interim protection of the "protected area": s. 3, being the Lemonthyme area and the Southern Forests area, other than any part of either area which is excluded from the protected area in the course of the inquiry: see the definition of excluded area in s. 3. The following description of the protected area is taken from the judgment of the Chief Justice granting an interlocutory injunction restraining the defendants from doing certain acts alleged to be unlawful under the Act: the Lemonthyme part of the protected area consists of 14,300 ha. approximately and the Southern Forests part 269,000 ha. approximately. Together they represent about 4.5 per cent of Tasmania's land surface. To the west of the protected area lie the Western Tasmanian Wilderness National Parks, covering 698,200 ha. In 1983 the World Heritage Committee included this area in the World Heritage List. The western boundary of the Lemonthyme area is approximately 50 km. long and is the eastern boundary of the World Heritage Area. The western boundary of the Southern Forests area is approximately 320 km. long and is, for 220 km. of its length, the eastern boundary of the World Heritage Area. The northern portion of the Southern Forests area is separated from the World Heritage Area, by State forest not within the protected area, Lake Gordon and the South West Conservation Area. The protected area contains substantial areas of State forest. Twelve per cent of the total area of State forest, amounting to 193,600 ha., lies within the protected area. The Court was informed that in excess of 200 ha. within the protected area are privately owned in fee simple. The defendants, supported by the Attorney-General for the State of Queensland as an intervener, argue that the Act, in particular Pt III, is invalid. A number of distinct arguments are advanced in support of that contention. First, it is submitted that, on the proper construction of the Convention, Australia is under no obligation to the international community to take measures for the protection of property which has not been identified by Australia as part of the world heritage situated within its territory. By way of answer, the Commonwealth relies on Arts. 3, 4 and 5 of the Convention, in particular upon Art. 5(d) which reads: To ensure that effective and active measures are taken for the protection, conservation and presentation of the cultural and natural heritage situated on its territory, each State Party to this Convention shall endeavour, in so far as possible, and as appropriate for each country: (d) to take the appropriate legal, scientific, technical, administrative and financial measures necessary for the identification, protection, conservation, presentation and rehabilitation of this heritage . It is submitted that the interim protection of an area during the process of identification and delineation of the world heritage (Art. 3) is a matter of express obligation under Art. 5(d) or alternatively is a matter which is reasonably incidental to the discharge of the obligation therein to identify the heritage. I do not think that the first of these propositions can be accepted, even allowing for the relaxed concept of "obligation" to be derived from the views of the majority in the Tasmanian Dam Case [37] . However, on the authority of that case, there is no escape from the conclusion that an obligation rests upon Australia to "endeavour, in so far as possible, and as appropriate to take the appropriate measures necessary for the identification of" the world heritage situated within its territory. That being so, the Commonwealth is on strong ground in relying on the authority of the Tasmanian Dam Case [38] for the further proposition that if and when the Commonwealth Parliament enacts legislation with the object of discharging an international obligation, the choice of means for achieving that object is for the Parliament and not for this Court so long as the law is capable of being reasonably considered to be appropriate and adapted to carrying out that object. The Parliament having established the Commission as a means of discovering whether there is located within the protected area any world heritage area or any area that contributes to the integrity or values of a world heritage area, there must be conceded to it the right to determine whether some form of interim protection of the protected area is appropriate. One may infer from s. 4 of the Act an expectation, albeit undefined, that some part of the protected area will be found to contain property which is fit for nomination to the World Heritage Committee for inclusion in the World Heritage List. It is impossible to deny to the Parliament, when once it has set in train procedures designed to identify within a defined area the existence of a world heritage area, a power to take appropriate measures to ensure that a world heritage is not damaged or destroyed during the process of identification. 1. (1983) 158 C.L.R., at pp. 132-136, 177-178, 220-228, 261-264. 2. (1983) 158 C.L.R., at pp. 130, 182, 232, 259-260. Of course, much may depend upon the protective measures that are put in place. The second submission of the defendants is that Pt III of the Act is invalid because it goes beyond what is capable of being reasonably considered to be appropriate and adapted to securing the object of identifying a world heritage. It is not reasonably proportionate to the end to be achieved. Reliance is placed upon a number of considerations: the absence of any defined expectation as to the existence of a world heritage area within the protected area; the size of the protected area, constituting about 4.5 per cent of the entire land mass of Tasmania; the comprehensive nature of the actions that are declared, unless done with the consent of the Minister, to be unlawful; the imposition on owners or occupiers of land within the protected area of a positive duty to take reasonable steps to prevent the commission on that land of any act rendered unlawful by the Act; the comparatively small part of the protected area which was intended to be the scene of forestry operations; the lack of regard to property rights within the area; the character of the dispensing power reposed in the Minister by s. 18(1), and the alleged unreviewability of the exercise of that power. In support of this submission, an analogy is sought to be drawn by the defendants between the acts rendered unlawful by s. 16(1) of the Act and the unlawful acts described in pars. (a) to (g) inclusive of s. 9(1) of the World Heritage Properties Conservation Act. In the Tasmanian Dam Case, both Brennan J. and Deane J. held those paragraphs to be invalid because they lacked proportionality to the obligation, to the discharge of which they were said to be related. But the vice of those paragraphs was the breadth of their application. Brennan J. [39] , explained his view thus: pars. (a) to (g) prohibit the doing of specified acts on every kind of identified property that Australia is obliged to protect and conserve. The protection and conservation of some properties may be ill-served by the imposition of such restrictions . The fact is that protection and conservation are functions that can only be performed with respect to an individual property; those functions have to be performed according to the condition of the property at the time and with reference to any threat that may then be posed by specific dangers . The difficulty with pars. (a) to (g) of s. 9(1) is that they generally prohibit the kinds of acts therein specified whenever done on any property to which s. 9 applies or may be made to apply. It is impossible to say that such provisions, in their application to all such properties at all times, would conduce to the protection and conservation of those properties. They are too wide. His Honour then considered whether the paragraphs were saved by the Minister's power to consent in writing to the doing of the acts mentioned. In providing a negative answer his Honour concluded that the statute failed "to provide an administrative system by which the discretion conferred on the Minister might ensure that the operation of the Act faithfully pursues the purpose of protection, conservation and presentation under the Convention" [40] . 1. (1983) 158 C.L.R., at pp. 236-237. 2. (1983) 158 C.L.R., at p. 237. To similar effect, Deane J. said [41] : The overall effect of s. 3(2), s. 6(2) and (3), s. 9(1) and s. 13(1) is that all of the prohibitions contained in pars. (a) to (g) (inclusive) of s. 9(1) are automatically imposed in respect of any property which is proclaimed by the Governor-General pursuant to s. 6(3) regardless of their appropriateness for the purpose of protecting or conserving the property and regardless of whether any relationship at all exists between all or any of the prohibited acts and the nature and source of likely damage to the property. In these circumstances, there is a lack of any reasonable proportionality between the provisions of s. 9(1)(a) to (g) and the purpose of protecting and conserving the relevant property. 1. (1983) 158 C.L.R., at pp. 266-267. The present Act is markedly different in several respects from the statute under consideration in the Tasmanian Dam Case. First, the range of acts declared by s. 16 to be unlawful is more circumscribed. Secondly, the prohibitions apply only within the protected area. Thirdly, the Minister may, either generally or as otherwise provided by the instrument of delegation, delegate his powers under s. 16: s. 23. In my opinion, these considerations render the attempted analogy inapt. There is no doubt as to the test which is to be applied in determining the defendants' submission on proportionality. It was stated succinctly by Barwick C.J. in Airlines of New South Wales Pty. Ltd. v. New South Wales [No. 2] [42] : Whilst the choice of the legislative means by which the treaty or convention shall be implemented is for the legislative authority, it is for this Court to determine whether particular provisions, when challenged, are appropriate and adapted to that end. 1. (1965) 113 C.L.R. 54, at p. 86. The Tasmanian Dam Case is authority for a somewhat expanded statement of the test, namely, that provided a law is capable of being reasonably considered to be appropriate and adapted to carrying out or giving effect to an object that impresses it with the character of a law with respect to external affairs, the choice of legislative means for achieving that object is for the Parliament and not for the Court. The application of the test to the circumstances of this case is not without difficulty. It cannot be said to be inappropriate for the Commonwealth to establish the Commission in order to ascertain the extent of its obligation, if any, in relation to the protected area. Nor is it unreasonable to suppose that the Commission may find that some part of the protected area will satisfy the definition of cultural or natural heritage set out in the Convention. That being so, the question is whether the protective provisions contained in s. 16(1) are capable of being seen as reasonably appropriate and adapted to enabling the fulfilment of Australia's obligations to identify and delineate the world heritage. The extent of the protected area is very large. The effect of Pt III of the Act is that 4.5 per cent of the land area of Tasmania is for all practical purposes transferred to the control of the Commonwealth. It at once raises the question — can such a serious interference with the affairs of Tasmania be justified as appropriate means directed to the achievement of the end? If forestry operations constitute the main threat to any world heritage that might be found to exist in the protected area, as would appear from a general reading of the Act to be the case, was it reasonably necessary to extend the control over 283,300 ha. when the threat was confined, according to the evidence received by the Chief Justice in the interlocutory proceeding already referred to, to an area of approximately 300 ha? On the other hand, there are countervailing considerations. Despite the size of the protected area, much of it is a wilderness area and the real impact of the protective provisions will be confined to the forestry operations. The protective regime is limited in duration to not later than the duration of the inquiry (which must be concluded within a period of twelve months: s. 3, definition of inquiry period) and forty-two days: s. 3, definition of interim protection period. The Commission is obliged to give priority to identifying any part or parts of the protected area that are definitely not qualifying areas and to report thereon as soon as practicable: s. 8(5). Within 14 days after receiving such a report, the Minister shall arrange for notice to be published in the Gazette , specifying the area or areas identified in the report: s. 20. Upon publication of the notice in the Gazette , the area or areas specified therein cease to be part of the protected area: s. 3, definition of excluded area and protected area. Provision is made for the payment of compensation to a person who suffers loss or damage because he refrains from doing an act made unlawful by s. 16(1) or is otherwise restrained by injunction from doing the act: s. 19(1). The compensation provisions extend to an owner of any part of the protected area who suffers loss or damage because another person has refrained from doing an act made unlawful by s. 16(1): s. 19(2). The prohibitions under s. 16(1) are not absolute, being subject to the consent of the Minister: s. 16(1) and s. 18(1). The Minister may delegate his power to grant consent: s. 23. Finally, the exercise of the Minister's power to consent or to withhold consent is subject to judicial review under the provisions of the Administrative Decisions (Judicial Review) Act 1977 Cth or by resort to the original jurisdiction of this Court conferred by s. 75(v) of the Constitution: cf. also s. 39B, Judiciary Act 1903 Cth. When all these various matters are taken into account, it is not possible, within the constraints imposed by the Tasmanian Dam Case, to uphold the second submission of the defendants. The protective provisions fall within the range of the discretion conceded to the Parliament in carrying out the obligation which the Convention imposes upon it. Finally, the defendants submit that the provisions of the Act, or alternatively the provisions of Pt III, are invalid because they interfere with, curtail or impair the legislative and executive functions of the State of Tasmania and the prerogative of the Crown in right of Tasmania in relation to its lands. Reliance is placed upon Melbourne Corporation v. The Commonwealth [43] and Queensland Electricity Commission v. The Commonwealth [44] . In the course of argument, counsel for the defendants pressed the argument on the basis that the Act discriminated against Tasmania. But, however the argument is put, in my opinion it cannot succeed. It cannot be said that the Act is discriminatory, in the sense that it singles out Tasmania. The protected area, in relation to which the object of the Act is to identify the existence of world heritage areas, if any, happens to be situated within Tasmania. The Act is not directed at Tasmania in any other sense or for any other reason. If the argument is put on the basis that the Act interferes with the legislative and executive functions of a State, that in itself is not sufficient to attract the limitation on Commonwealth legislative power that is to be implied from the Constitution. A similar argument was advanced and rejected in the Tasmanian Dam Case. There, Mason J. said [45] : To fall foul of the prohibition, in so far as it relates to the capacity of a State to govern, it is not enough that Commonwealth law adversely affects the State in the exercise of some governmental function as, for instance, by affecting the State in the exercise of a prerogative. Instead, it must emerge that there is a substantial interference with the State's capacity to govern, an interference which will threaten or endanger the continued functioning of the State as an essential constituent element in the federal system. See also per Brennan J. [46] ; and Deane J. [47] A little later in his judgment, Mason J. mentioned an aspect of the matter which may be thought to have some relevance to the present case. His Honour said [48] : It is perhaps possible that in some exceptional situations if the area of land affected by Commonwealth prohibitions similar to those imposed by reg 5 forms a very large proportion of the State, the imposition of the prohibitions would attract the Melbourne Corporation principle. But this is certainly not the case here, where the Regulations affect 14,125 ha. only. As I have said, the Commonwealth's assertion of authority affects some 283,300 ha., amounting to about 4.5 per cent of the entire territory of Tasmania. However, despite the size of the affected area, having regard to the nature of the area, the limited scope that it offers for the exercise of ordinary governmental functions, the limited duration of Commonwealth control and the procedure for the early exclusion of parts of the protected area from that control, there is no warrant for invoking an implied limitation upon the exercise of a legislative power expressly granted to the Commonwealth by s. 51 of the Constitution. 1. (1947) 74 C.L.R. 31. 2. (1985) 159 C.L.R. 192. 3. (1983) 158 C.L.R., at p. 139. 4. (1983) 158 C.L.R., at pp. 208-216. 5. (1983) 158 C.L.R., at pp. 280-281. 6. (1983) 158 C.L.R., at p. 141. Before concluding, I should refer to another argument advanced by counsel for the Attorney-General for Queensland. Counsel drew attention to the reference in the definition of qualifying area in s. 3 to "an area that contributes to the integrity or values of a world heritage area". He submitted that because the Commission is required merely to report on whether there are any qualifying areas within the protected area without distinguishing between those parts which constitute a world heritage area and those parts which merely contribute to the integrity or values of a world heritage area, it cannot be said that the Act is a faithful pursuit of the international obligation to identify a world heritage area. A reading of the Act does not make clear the legislative purpose leading to the inclusion of the reference to areas contributing to the integrity or values of a world heritage area in the definition of qualifying area. The Convention does not use the phrase. It may be wondered why an area that contributes to the integrity or values of a world heritage area is not so intimately connected to the latter as to form part of it. However, such an approach might encounter difficulty with the specific wording of the relevant part of the definition of "natural heritage" in the Convention which refers to "precisely delineated natural areas of outstanding universal value from the point of view of science, conservation or natural beauty": Art. 2. Alternatively, it is conceivable that a duty to protect an identified world heritage area would attract a power to extend the protection to an area which contributes to the integrity or values of the former; however, that proposition cannot avail the Commonwealth here, because there is as yet no identified world heritage area within the protected area. Furthermore, the Act does not require the Commission to distinguish between the two kinds of area. Nevertheless, despite the intriguing questions that the use of the phrase is capable of raising, I do not think that its inclusion has the effect of placing the Act beyond power. It must be remembered that it is not the task of the Commission itself to identify and delineate the world heritage area that may be situated within the protected area. Its task is to produce a report which the Parliament anticipates will assist the Commonwealth in discharging its obligation to "endeavour, in so far as possible, and as appropriate to take the appropriate measures necessary for the identification of [the] heritage" (Art. 5(d)) that may be present within the protected area. In the same way as the task imposed upon the Commission by s. 8 to report on matters relating to the exploitation of forestry resources elsewhere in Tasmania is calculated to assist the Commonwealth in deciding what is appropriate and possible in the matter of identifying and protecting additional areas of world heritage situated within the protected area, it is not unreasonable to suppose that the report of the Commission in relation to areas within the protected area that contribute to the integrity or values of a world heritage area therein will assist the Commonwealth in its appreciation of the heritage potential of the area. It is sufficient for validity that the appointment of the Commission with its terms of reference is a measure that will facilitate governmental decisions respecting Australia's obligations under the Convention, in particular the obligation to identify and delineate the world heritage, if any, within the protected area in so far as it is possible and appropriate to do so. I would hold the Act valid. Deane J. It is now more than half a century since this Court recognised, in R. v. Burgess; Ex parte Henry [49] , that the grant of legislative power contained in s. 51(xxix) of the Constitution must be given its full effect and is not to be limited by reference to preconceptions of the extent of the residue of legislative powers retained by the States or by the notion that to give the words comprising that grant their full effect would somehow imperil the constitutional balance between the Commonwealth and the States. In that regard, Burgess effectively represented no more than the application of the compelling reasoning of the Engineers' Case [50] . Indeed, it would have been to turn logic on its head to define the content of a specific grant of Commonwealth legislative power by reference to a counterpoint measure which could only be identified after the full scope of that Commonwealth power had been determined or to see acceptance of the effect of the actual words of the Constitution conferring legislative power as imperilling an overall constitutional balance which could only be struck after full account had been taken of those same words: see Burgess [51] . 1. (1936) 55 C.L.R. 608. 2. (1920) 28 C.L.R. 129. 3. (1936) 55 C.L.R., at pp. 636-637, 680. That is not to say that the specific grants of Commonwealth legislative power are to be construed as in a vacuum or without regard to their context in the constitution of a federation. In particular, that constitutional context precludes the approach that the Parliament of the Commonwealth itself can foreclose, by express assertion either of statutory character or of legislative intention or purpose, the question whether a proposed law is or is not one with respect to a designated head of Commonwealth legislative power. It is to this Court that the people have entrusted the ultimate responsibility of determining whether a law which the Parliament has purported to impose comes within the scope of the legislative powers which they have conferred upon the Parliament. The settled judicial process by which the Court must discharge that responsibility is that of characterization of the impugned law by reference to its substantive operation. Ordinarily, that process of characterization will involve no more than consideration of the law's objective legal operation without regard to any ulterior legislative purpose or object. There are, however, circumstances in which characterization of a law requires that regard be paid to any such purpose or object. The obvious example of such circumstances is the case where the direct legal operation of a law does not of itself suffice to characterize it as a law with respect to a subject-matter of Commonwealth legislative power but some ulterior purpose or object which the law was enacted to serve may suffice to warrant characterization of it as a law with respect to such a subject-matter. Such characterization by reference to underlying purpose or object will only be possible if the designated legislative power itself "involves the notion of purpose or object": see per Dixon J. Stenhouse v. Coleman [52] . The "naval and military defence" of the Commonwealth and the States (Constitution, s. 51(vi)) is one of the main subject-matters of Commonwealth legislative power which fall within that category. External affairs is another: see the Tasmanian Dam Case [53] . The primary purpose or object of the one is the conduct, advancement and discharge of the nation's naval and military defence and the power extends to authorize the enactment of some purely civilian measures for the pursuit of that purpose or object. The primary purpose or object of the other is the conduct of the nation's international affairs, including the advancement of its international relations and interests and the discharge of its international obligations, and the power extends to authorize the enactment of some purely domestic measures for the pursuit of that purpose or object. As Latham C.J. commented in Burgess [54] : The execution and maintenance of the Constitution, particularly when considered in relation to other countries, involves not only the defence of Australia in time of war but also the establishment of relations at any time with other countries, including the acquisition of rights and obligations upon the international plane. The Commonwealth Parliament was given power to legislate to give effect to international obligations binding the Commonwealth or to protect national rights internationally obtained by the Commonwealth whenever legislation was necessary or deemed to be desirable for this purpose. Thus, the external affairs power encompasses the purposive power to carry out treaties by domestic legislation: "all powers necessary or proper for performing obligations towards foreign countries, arising under treaties": cf. British North America Act 1867, s. 132 and per Latham C.J., Burgess [55] . It authorizes not only domestic laws enacted for the purpose of "a carrying out" of the external obligation but also laws providing for "anything reasonably incidental to the execution of [that] purpose" per Dixon J. [56] . In Burgess [57] Dixon J., having commented that the view that the external affairs power conferred legislative authority to implement an international agreement relating "only to matters otherwise only" of internal concern "seems" an extreme one, deferred a consideration of the validity of that view "until questions arise under" such agreements. No such reservation was made by Latham C.J., Evatt and McTiernan JJ. however and Burgess is plain authority for the proposition that the legislative power includes the power to execute within the Commonwealth treaties and conventions entered into with foreign powers regardless of their subject-matter. The power also authorizes domestic laws "designed to promote friendly relations with all or any of the nations" (per Evatt and McTiernan JJ. [58] ) or to achieve some other international purpose or object. 1. (1944) 69 C.L.R. 457, at p. 471. 2. (1983) 158 C.L.R. 1, at pp. 259-261. 3. (1936) 55 C.L.R., at p. 644. 4. (1936) 55 C.L.R., at pp. 637-643. 5. (1936) 55 C.L.R., at p. 674. 6. (1936) 55 C.L.R., at p. 669. 7. (1936) 55 C.L.R., at p. 684. When the direct operation of a law is with respect to an external or international subject-matter, ordinary processes of characterization can be applied and the nature of the law as a law with respect to external affairs will be disclosed by its bare legal operation. A law authorizing the establishment of an overseas embassy and a law ratifying or approving an international treaty or the constitution of an international organization (see, e.g., s. 3 of Acts Nos. 79, 80, 81, 82 and 83 of 1947 and s. 2 of Act No. 24 of 1947) are examples of a law with such direct operation. On the other hand, a law whose direct operation is solely with respect to a domestic subject-matter which is not of itself within the ambit of external affairs may, in some circumstances, properly be characterized as a law with respect to external affairs for the purposes of s. 51(xxix) of the Constitution by reference to some identified purpose or object which its operation is designed to advance or achieve. The mere fact that there can be discerned some purpose or object, being a legitimate subject-matter of external affairs, which the impugned law is designed to advance or achieve will not, of itself, suffice for such characterization. Such a purpose or object must pervade and explain the substantive operation of the impugned law to an extent that warrants characterization of the law as a law with respect to external affairs notwithstanding the fact that its bare legal operation is with respect to a domestic or completely internal subject-matter. At a later stage of this judgment, I examine this requirement in some detail. There is inevitably a degree of tension between the legislative function of the Parliament and the judicial function of the court in cases where legislative competence is claimed by reference to such an underlying purpose or object rather than by reference to the bare operation of the particular law. It is for the Parliament and not for the court to decide what are the appropriate legislative provisions to achieve a desired result. On the other hand, nowhere is the role of the court as the ultimate custodian of the provisions of the Constitution more critical than in a case where challenged legislation is claimed to be within legislative competence on the ground that, notwithstanding that it does not directly operate with respect to a designated subject-matter of legislative power, its underlying purpose or object gives it the character of a law with respect to external affairs (s. 51(xxix)) or defence: s. 51(vi). In the context of the scope of contemporary international relations and of the nature of modern warfare, there are few domestic laws which could not arguably be seen as capable of affecting or bearing upon the country's external affairs or defence. It would, however, be to ignore the constitutional context of the specific grants of legislative power contained in pars. (xxix) and (vi) of s. 51 to hold that the fact that the economic, social and moral well-being of the Commonwealth and its citizens is conducive to international standing and prestige, to the domestic observance of fundamental human rights and other standards or objectives enshrined in international conventions and to an adequate defence establishment or capacity, means that the combined effect of those two sub-sections is effectively to confer general legislative powers on the Parliament with respect to the economic, social and moral well-being of the Commonwealth and its citizens, subject only to the proviso that it must be possible to identify, in the case of an impugned law, a relevant purpose of advancing or serving the nation's external affairs or defence. More particularly, and closer to the present case, it would be to ignore the constitutional context of s. 51(xxix) to hold that the mere legislative or administrative assertion of the existence of an underlying purpose of ensuring local observance of such international standards or objectives would suffice to impart the character of a law with respect to external affairs to the legislative imposition of a Commonwealth regime of complete control or compulsory inactivity upon the whole or a significant part of a particular State. In the Tasmanian Dam Case [59] , I sought to explain what I see as the appropriate test for determining whether a law whose direct operation is upon a domestic subject-matter can properly be characterized as a law with respect to external affairs by reason of some ulterior legislative purpose or object which it was enacted to advance or achieve. I did so in terms which were largely borrowed from the cases to which I there referred. In the following paragraph, I venture to repeat, in a slightly expanded form, what I there wrote. 1. (1983) 158 C.L.R., esp. at pp. 259-269. First, there must be identified a purpose or object, itself a legitimate subject of external affairs: eg the carrying into effect of a treaty, the performance of an international obligation or the obtaining of an international benefit. The reference to such a purpose or object is not, of course, to the subjective motives or purposes of the various members of the Parliament which enacted the law. It is a reference to the purpose or object of the law itself — that which it can be seen to be designed to serve or achieve. As Dixon J. commented in Stenhouse v. Coleman [6] : "No doubt it is possible that the "purpose" here may be another example of what Lord Sumner described as "one of those so-called intentions which the law imputes; it is the legal construction put on something done in fact": Blott's Case [7] ." Dixon J. went on to note that "apparently the purpose must be collected from the instrument in question, the facts to which it applies and the circumstances which called it forth". Secondly, to repeat what has been said above, that purpose or object must pervade and explain the operation of the law to an extent that warrants the overall characterization of the law as one with respect to external affairs; it "must be seen, with "reasonable clearness", upon consideration of its operation, to be "really referable" to and explicable by the purpose or object which is said to provide its character": the Tasmanian Dam Case [8] . While the question of what is the appropriate method of achieving a desired result is a matter for the Parliament and not for the court, the operation of a law will not properly be seen as explained by the designated purpose or object unless it appears that that operation is capable of being reasonably considered to be appropriate and adapted to achieve it. Such a law will not be capable of being so seen unless it appears that there is "reasonable proportionality" between that purpose or object and the means which the law adopts to pursue it. The reason for such a requirement was explained, again by Dixon J., in Burgess [9] when his Honour commented that the nature of the external affairs power "necessitates a faithful pursuit of the purpose before it can support the imposition upon citizens of duties and disabilities which otherwise would be outside the power of the Commonwealth". His Honour added [10] that "under colour of carrying out an external obligation the Commonwealth cannot undertake the general regulation of the subject-matter to which it relates". 1. (1944) 69 C.L.R., at p. 471. 2. [1921] 2 A.C. 171, at p. 218. 3. (1983) 158 C.L.R., at p. 260. 4. (1936) 55 C.L.R., at p. 674. 5. (1936) 55 C.L.R., at pp. 674-675. It should be mentioned that, in the above formulation, I have stated the requirement relating to the impugned law being "appropriate and adapted" in less stringent terms (from the point of view of the Commonwealth) than those used in some previous judgments in this Court. In particular, in Airlines of New South Wales Pty. Ltd. v. New South Wales [No. 2] [11] , Barwick C.J. expressed the view that "it is for this Court to determine whether particular provisions, when challenged, are appropriate and adapted to" the particular "end". In my view, it is not necessary for this Court to be persuaded that the particular provisions are, in fact, appropriate and adapted to the designated purpose or object. That is a matter for the Parliament. Obviously, the relevant requirement will be satisfied if the Court is so persuaded. As I have indicated however, it will, in my view, suffice if it appears to the Court that the relevant provisions are capable of being reasonably considered to be so appropriate and adapted: cf. per Starke J., Burgess [12] . In a case where the direct operation of a law is with respect to purely domestic matters, it is, however, for the Commonwealth or those who would sustain the validity of the law by reference to ulterior object or purpose to point to material which makes it possible to say that the law can be characterized as a law with respect to external affairs by reason of that underlying purpose or object. 1. (1965) 113 C.L.R. 54, at p. 86. 2. (1936) 55 C.L.R., at pp. 659-660. The first question reserved for the decision of this Full Court in the present case raises for consideration the validity of the provisions of the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act") which was purportedly enacted by the Parliament of the Commonwealth in reliance upon the external affairs power. The contextual facts, the relevant statutory provisions and the critical clauses of the Convention for the Protection of the World Cultural and Natural Heritage ("the Convention") are set out or summarized in the judgments which precede this. Except to the extent necessary for meaningful discussion, I shall avoid repetition of them. The provisions of the Act, read in the context of the material before the Court, disclose that a purpose or object which the Act as a whole is designed to serve is the identification, delineation and protection of actual and potential world heritage areas and the procurement of information and advice with respect to that identification and delineation and with respect to related questions, such as the relationship between world heritage areas and adjoining areas and the availability of alternative resources. Those are all matters involved in, or conducive to, the identification, discharge and pursuit of the international obligations, aspirations and objectives which Australia undertook or to which it subscribed by becoming a party to the Convention. That being so, an underlying purpose or object which the Act manifests is a legitimate subject of external affairs, namely, the discharge and pursuit of obligations, aspirations and objectives imposed or recognized and accepted by an international treaty to which Australia is a party. It will, on occasion, be convenient to refer to that purpose or object as "the international purpose or object". It can be said at once that the provisions of Pt II of the Act, which are concerned with the actual establishment and conduct of the Commission of Inquiry into the Lemonthyme and Southern Forests areas (the protected areas) and which are plainly severable from the provisions of Pt III (see below), are plainly within the legislative competence of the Parliament to make laws with respect to external affairs. There is much to be said for the view that the bare legal operation of those provisions is, in the context of the nature of the subject-matters entrusted to the Commission for investigation and advice, such as to warrant their characterization as a law with respect to external affairs without there being any need to take account of underlying purpose or object. However, it is unnecessary to pursue that question since, even if it be necessary to resort to the international purpose or object, it is apparent that that purpose or object, being itself a legitimate subject of external affairs, pervades and explains those particular provisions of the Act in a way that would, in any event, warrant their characterization as a law with respect to external affairs. Plainly, those particular provisions are capable of being reasonably considered to be appropriate and adapted to achieve that underlying purpose or object. In that regard, the wide extent of the areas in respect of which the Commission is charged to inquire and advise is unimportant. Indeed, it would not affect the validity of the provisions of the Act actually establishing the Commission and regulating its conduct if the Commission had been entrusted with obtaining information of the relevant type and formulating advice of the kind which it is required to provide in respect of the whole land area of the Commonwealth. It follows that, even if it be assumed that the direct operation of those particular provisions is in relation to domestic matters, they are properly to be characterized as a law with respect to external affairs and are accordingly within the legislative power conferred upon the Parliament by s. 51(xxix). Once one passes from the provisions of the Act concerned with the actual establishment and conduct of the Commission (i.e. Pt II) to the provisions of the Act concerned with the interim preservation and protection of the protected areas (i.e. Pt III), one passes from provisions aimed at obtaining information and advice to provisions establishing a legislative regime which, to a significant degree, prevents or freezes the development and inhibits the use of the lands to which it applies. As has been said, the protection of actual and potential world heritage areas is a purpose or object to which Australia has subscribed by becoming a party to the Convention. It is, however, far from self-evident that a law establishing a conservation regime of direct Commonwealth control, in relation to domestic matters which are not of themselves subjects of Commonwealth legislative or administrative powers, over a large area of State territory containing no listed or nominated world heritage areas, can properly be characterized, for the purposes of s. 51(xxix), as a law with respect to external affairs simply because the affected territory is adjacent to World Heritage areas or is said to include some parts which could be considered as natural or cultural heritage appropriate for nomination for World Heritage listing. Even if it be accepted that the international purpose or object underlies the provisions of the Act imposing the restrictive Commonwealth regime, those provisions will, as has been seen, bear the character of a law with respect to external affairs for the purposes of s. 51(xxix) only if it appears that their domestic operation to impose and provide for the enforcement of restrictions and restraints in relation to the protected areas is reasonably capable of being seen as appropriate and adapted to the genuine pursuit of that purpose or object. It is the question whether it appears that the domestic operation of those provisions is reasonably capable of being so seen which lies at the heart of the present case. I turn to a consideration of it. Section 16 of the Act would, if valid, effectively prohibit logging operations within the protected areas for a period which might persist for 12 months from the time of the establishment of the Commission. The prohibition would not be confined to felling trees in the course of forestry operations. It would extend to removal of any part of a tree in the course of such operations, even one felled before the enactment of the Act. More important, the protective regime which s. 16 of the Act purports to establish would involve much more than a prohibition of logging operations. As has been said, it would represent an effective prohibition or freeze of any development be it, e.g., for minor tourist purposes or even for protective purposes (eg the building or maintenance of fire-breaks), within the areas to which it applied. No vehicular track, however narrow, temporary or short or for whatever purpose, could be constructed: s. 16(1)(b). No excavation work, however small, could be made: s. 16(1)(c). No other act which "is capable of" adversely affecting the protected areas and which is "prescribed for the purposes of this paragraph" could be done even though in actual fact it would, on balance, benefit the area: s. 16(1)(d). The imposed regime would go even further and encompass the imposition of an obligation to take positive action: the owner or occupier of any part of the protected areas would be obliged to take reasonable steps to prevent the doing within that part of any of the prohibited acts. It is true that the prohibition might be lifted by the Minister with respect to particular acts or classes of acts or persons or classes of persons. The fact that a prohibition upon acts in a remote area of Tasmania will be lifted if a discretionary permission can be obtained from a Commonwealth Government Minister does not, however, change its nature as a prohibition either in regard to its primary operation or in so far as the citizen who remains subject to it is concerned: cf. Swan Hill Corporation v. Bradbury [13] ; Hughes and Vale Pty. Ltd. v. New South Wales [14] . Nor, in my view, does the fact that a refusal to grant such a discretionary permission may, if the person concerned has the necessary knowledge, means and determination, be reviewed pursuant to the Administrative Appeals Tribunal Act 1975 Cth effect such a change. Moreover, any such power to grant permission either initially or on review is strangely confined in that the Minister, "[i]n determining whether or not to give a consent" (emphasis added), is constrained to have regard " only " to Australia's obligations under the Convention: s. 18(1). If that precludes the Minister from having regard to considerations such as the hardship suffered by the particular applicant for consent, the power to relax the prohibition would border upon the illusory. It is, however, unnecessary to pursue that point. 1. (1937) 56 C.L.R. 746, esp. at p. 762. 2. (1954) 93 C.L.R. 1, at p. 26. There could be circumstances in which the establishment, on an interim or permanent basis, of a legislative regime of the type established by Pt III of the Act could be justified as capable of being reasonably considered to be appropriate and adapted to achieving the discharge of Australia's obligations under the Convention and the pursuit of international aspirations and objectives in relation to the Convention. In the present case, however, no real attempt has been made to demonstrate that the overall protective regime established by Pt III is in fact capable of being reasonably considered to be so appropriate and adapted. There is nothing at all to suggest that there exists an identified threat of anything other than logging operations to any part of the protected areas. Indeed, there has been no effort to identify to the Court the activities of those persons, other than forestry operators, whose use of land or earning of livelihood might be interfered with or precluded by the operation of the protective regime. The Court was informed that there are areas of freehold land owned by individuals within the protected areas. Insignificant though those areas may be in the overall perspective from Canberra, their owners, few though they may be, are citizens whose lives and property are beyond the reach of the Parliament except to the extent authorized by a relevant grant of Commonwealth legislative power. Yet there was no effort by the Commonwealth to justify the application of the protective regime, with all its stringency, to those privately owned areas of freehold land. Indeed, at times in the argument, it seemed that the Commonwealth had not ascertained what the practical impact of the imposition of the restrictive regime would be on the lives and livelihood of those who own or use land within the protected areas for other than logging purposes. Be that as it may, the blanket prima facie prohibition throughout the whole of the protected areas of the making of even a minor temporary vehicular track or small excavation works remains without plausible justification. If the protected areas were of small dimensions, the above considerations may be less than compelling. The Court was informed, however, that the protected areas represent some 4.5 per cent of the whole land surface of the State of Tasmania. If it could be said that the Commonwealth had had no opportunity to acquire information about any activities, other than the confined (in terms of area) forestry activities, within the protected areas, that would at least provide some explanation of the lack of justification or information. That has not, however, been suggested and the history of past negotiations between the Commonwealth and Tasmania would not lead one readily to assume or to accept the absence of any such opportunity on the part of the Commonwealth. The fact that the material before the Court is unsatisfactory and incomplete cannot absolve the Court of its constitutional responsibility to decide the question whether, to repeat Dixon J.'s words, "the imposition upon citizens of duties and disabilities which otherwise would be outside the power of the Commonwealth" can be justified by resort to the external affairs power. When that question is fairly faced, the material before the Court leads inevitably to the conclusion that there has been no real effort made to confine the prohibitions of the overall protective regime, with the overriding of the ordinary rights of citizens and the ordinary jurisdiction of the State of Tasmania which it would involve, to activities which it might reasonably be thought represented some real actual or potential threat to what might properly be seen, for the purposes of the Convention, as natural or cultural heritage. It is true that the Act contains provisions designed to enable parts which definitely involve no natural or cultural heritage to be subsequently excluded from the protected areas. However, those provisions raise as many questions about the possible justification of the extent of the protected areas as they answer. It is also true that, as has been said, the protective regime will, unless the Act is amended, not last for more than twelve months and that, as has been seen, there is provision enabling the Minister to permit otherwise prohibited acts. However, neither that limited maximum period nor the possibility of such consent changes the essential character of the overall protective regime. On the material before the Court, it is impossible to say that it appears that there is reasonable proportionality between the provisions of Pt III of the Act, when they are viewed as a whole, imposing that overall restrictive regime and the designated intention, purpose or object. That being so, those provisions are not, when so viewed, capable of being reasonably considered to be appropriate and adapted to achieve the purpose or object which is said to provide them with the character of a law with respect to external affairs. Accordingly, the provisions of Pt III of the Act cannot, taken collectively, be sustained by s. 51(xxix) of the Constitution. The question arises whether those provisions of Pt III are all invalid or whether some of them are severable and either valid, when viewed independently, or susceptible of being read down to validity. The starting point of a consideration of that question must lie in an examination of the content of, and the interrelation between, the various paragraphs of s. 16(1) which impose the relevant primary prohibitions. It should be apparent, from what has been said above, that I consider that the blanket proscription of the construction or establishment, without prior ministerial consent, of any road or vehicular track within any part of the protected areas (s. 16(1)(b)) is invalid. The same can be said of the proscription of the carrying out, in any part of the protected areas, of any excavation works (s. 16(1)(c)) and of the proscription of the doing of any act at all which may be prescribed by administrative action (s. 24(a)) and is capable of adversely affecting the protected areas: s. 16(1)(d). None of those proscriptions can properly be read down to validity. They are, however, plainly distinct from that contained in par. (a) of s. 16(1) which can be severed from them. That paragraph makes it unlawful "for the purposes of, or in the course of carrying out, forestry operations, to kill, cut down or damage a tree in, or remove a tree or a part of a tree from, the protected area". As I have indicated the prohibition of removal of a tree from any part of the protected areas would extend to preclude the removal of any timber regardless of when the trees from which it was extracted were felled. There is nothing in the material in evidence which appears to be directed to demonstrating, or even suggesting, that such a prohibition could reasonably be seen as necessary to enable effective enforcement of the prohibition upon felling. To the contrary, the evidence is to the effect that there were quantities of felled timber within the protected areas (in coupe LA45) which all parties agreed should be permitted to be removed. Regardless of whether that removal was to be pursuant to formal consent or informal arrangement, the overall evidence does not support the existence of the requisite element of proportionality between a general prima facie proscription of the removal of any timber and the designated international purpose or object. On the other hand, the prohibition of active logging operations (ie killing, cutting down or damaging a tree or part of a tree for the purposes of, or in the course of carrying out, forestry operations) within the protected areas is severable from the prohibition of removal of a tree or part of a tree. That prohibition of active logging operations falls within a different category from all the other prohibitions contained in s. 16(1) in that it is confined to activities which are obviously capable of being seen as constituting a threat to the preservation of any actual or potential world heritage areas in which they were carried on. If the prohibition of active logging operations throughout the whole of the protected areas was for an indefinite period, it would be difficult to justify it in a context where the evidence indicates that less than one half of the protected areas could, in fact, be realistically seen as under any threat of active logging operations: see, e.g., Richardson v. Forestry Commission [15] . Viewed as a temporary measure designed to provide interim protection pending the receipt of further information and advice however, the proscription of active logging operations is, on the material before the Court, reasonably capable of being seen as appropriate and adapted to the international purpose or object. In that regard, the failure to identify actual or potential world heritage areas within the protected areas is explicable by the need for the interim protection of the whole pending the outcome of an inquiry aimed, among other things, at such identification. The fact that the proscription of active logging operations applies to parts of the protected areas notwithstanding the absence of any real threat of logging operations in respect of those particular parts does not deprive the proscription of the element of proportionality. The reason for that is that the operative effect of the proscription will only be significant in relation to those areas where active logging operations otherwise would or might have occurred. In my view, the proscription of active logging operations contained in s. 16(1)(a) can, when viewed on its own, properly be characterized, by reference to the international purpose or object, as a law with respect to external affairs for the purposes of s. 51(xxix). That proscription is severable from the other provisions of s. 16(1) and is valid. 1. Ante, p. 269. The provisions of s. 16(2) and (3) and the other provisions of Pt III of the Act are dependent for their operation upon the provisions of s. 16(1). Their validity is not, however, affected by the partial invalidity of s. 16(1). They remain valid and operative in relation to so much of s. 16(1) as is valid. It was submitted on behalf of the Commonwealth that if the conclusion would otherwise be reached that, on the material before the Court, some or all of the provisions of Pt III of the Act were invalid, the Commonwealth should be accorded the opportunity of placing further material before the Court. Since a majority of the Court is of the view that the provisions of Pt III of the Act are, in any event, wholly valid, it is unnecessary for me to reach a conclusion in relation to that submission. I shall however, in deference to it, qualify my answer to the first question reserved for the opinion of the Court in so far as that answer relates to that part of s. 16(1)(a) which I would, on the material at present before the Court, hold to be invalid. I would not so confine that answer in so far as it relates to s. 16(1)(b),(c) and (d) since there is nothing which leads me to think that there is any real likelihood that my conclusion that those paragraphs are invalid could be avoided by reference to further material. In terms, question one asks: "To what extent, if any, is the Act invalid?" I would answer it: "The provisions of s. 16(1)(b), (c) and (d) are all invalid. On the material presently before the Court, the proscription in s. 16(1)(a) of the removal of a tree or a part of a tree is invalid." The second question concerns the availability of what were pleaded as discretionary defences against the grant of injunctive relief at the suit of the Commonwealth against alleged breaches by the defendants of the provisions of Pt III. I agree, for the reasons which they give, that that question should be dealt with in the manner indicated in the judgment of the Chief Justice and Brennan J. There is one further matter which I would briefly mention. It is that it should be stressed that the function of the Full Court in these proceedings is confined to determining the legal questions reserved for its consideration. It is no part of that function to determine whether, regardless of performance of international obligation or pursuit of international objective, the obvious general need to safeguard the Australian environment makes it desirable that an overall conservation regime of the type purportedly imposed by the provisions of Pt III of the Act should be imposed in respect of all or part of the protected areas. The point on which this judgment turns is a general principle of constitutional law. It is that, if the Parliament of the Commonwealth seeks to impose restrictions and obligations upon a State and citizens in respect of domestic subject-matters which do not prima facie lie within its legislative competence on the basis that some underlying international purpose or object characterizes the provisions imposing such restrictions and obligations as a law with respect to external affairs, it is for the Commonwealth (in this case through the plaintiff as the relevant Commonwealth Minister) or those who would uphold the validity of those provisions on that basis to point to material which makes it possible to say that the provisions are at least capable of being reasonably seen as appropriate and adapted to advance or achieve that purpose or object. In my view, that is something which the Commonwealth has, in the present case, signally failed to do in so far as the prohibitions which the Act would impose in relation to 4.5 per cent of the State of Tasmania extend beyond active logging operations. Dawson J. In The Commonwealth v. Tasmania ("the Tasmanian Dam Case ") [16] , the majority took the view that legislation implementing the Convention for the Protection of the World Cultural and Natural Heritage was a valid exercise of the external affairs power contained in s. 51(xxix) of the Constitution. That view was taken, as I read the judgments, upon the basis that subject to express constitutional prohibitions, any matters covered by a bona fide international treaty are, by their very inclusion in the treaty, brought within the ambit of the external affairs power. As will be apparent from my reasons for judgment in the Tasmanian Dam Case, I am unable to accept that view. No doubt the activities involved in concluding an international agreement fall within the description of external affairs, but that does not to my mind bring the subject-matter of the agreement, if it is otherwise entirely domestic, within that description. In my view it is quite wrong to conclude that, because the scope of matters which are the subject of treaties has in modern times greatly expanded, the scope of the external affairs power has undergone the same expansion. The fact that an agreement is international in character does not necessarily mean that the matters with which it deals cease to be of a domestic nature and become part of the country's external affairs. Just as, in another context, the Constitution requires us to distinguish between interstate and intrastate trade, so we must distinguish between affairs which are external and those which are not. And just as the fact that a contract is made over State boundaries will not determine whether the subject-matter of the contract is interstate or intrastate trade, so the fact that an agreement is made internationally will not determine whether its subject-matter is external or domestic in character. Since there is no practical limit to those matters which may form the subject of international agreement, the result of taking the opposite view is that there is no practical limit to the scope of the external affairs power. That is to say, the result is that par. (xxix) has the potential to obliterate the division of legislative power otherwise effected by s. 51. Simply as a matter of construction, I cannot believe that such a result was ever intended. 1. (1983) 158 C.L.R. 1. However, I do not refer to these considerations merely to reiterate a view which did not find favour in the Tasmanian Dam Case. I mention them to indicate that my difference with the majority is upon a matter of fundamental importance. The course which I should adopt in these circumstances is not altogether clear. Plainly enough, if, as is the case, I do not think that the Constitution admits of any other interpretation, it is the words of the Constitution rather than authority which should govern any decision I might make. If I were asked to do so, I should find the greatest difficulty, notwithstanding the course taken in Queensland v. The Commonwealth [17] , in deciding that the Constitution said something which I thought it did not. This Court has never held itself to be bound by its own decisions and ultimately it is the Constitution itself, and not authority, which must dictate the answers which we give: see Australian Agricultural Co v. Federated Engine-Drivers and Firemen's Association of Australasia [18] , per Isaacs J.; the Tramways Case [No. 1] [19] , per Isaacs J. 1. (1977) 139 C.L.R. 585. 2. (1913) 17 C.L.R. 261, at pp. 275-279. 3. (1914) 18 C.L.R. 54, at p. 70. Precedent must, however, have a part to play, even in the interpretation of a constitution. Considerations of practicality make it necessary that the law should, as far as possible, take a consistent course. The constant re-examination of concluded questions is incompatible with that aim. That is why this Court has adopted the practice of requiring leave to be granted before it will allow a previous decision to be re-argued: Evda Nominees Pty. Ltd. v. Victoria [20] . The parties in the present case did not seek to question the decision in the Tasmanian Dam Case. In these circumstances, and having made my own view clear, it is, I think, proper to proceed upon the same basis as did the argument in this case and to assume the authority of that decision. 1. (1984) 154 C.L.R. 311. The Tasmanian Dam Case does, I think, provide an answer in the present case because whatever else it decided, it did decide that the legislative implementation of an international treaty concluded in good faith is within the ambit of the external affairs power. True it is that the Tasmanian Dam Case appears to have decided more than this. As I read the judgments of the majority, it is enough to attract legislative power if, even though there is no treaty, a subject-matter is of sufficient international concern per Mason J. [21] ; per Murphy J. [22] ; per Brennan J. [23] ; and per Deane J. [24] . Although the majority did not necessarily place any reliance upon the judgment of Stephen J. in Koowarta v. Bjelke-Petersen [25] , that conclusion flows logically from the view which he expressed that the implementation of a treaty is not automatically an exercise of the external affairs power; the subject-matter of the treaty must also be a matter of international concern. Stephen J. saw the requirement of international concern as a restriction upon the power and I was prepared to view it in that way in the Tasmanian Dam Case. But in reality, as the decision in the latter case shows, the fact that a matter is the subject of a bona fide treaty makes it difficult to say that it is not a matter of international concern and, if international concern is the touchstone, why is a treaty necessary at all? Why is international concern over a matter not sufficient of itself to bring it within the external affairs power? 1. (1983) 158 C.L.R., at pp. 129-132. 2. (1983) 158 C.L.R., at pp. 171-172. 3. (1983) 158 C.L.R., at p. 222. 4. (1983) 158 C.L.R., at pp. 258-259. 5. (1982) 153 C.L.R. 168. If the scope of the matters which may be the subject of treaties has greatly expanded in recent years, the scope of those matters which may be the subject of international concern is even wider. It is not, therefore, surprising to find a search for some limit to the breadth which, upon this expansive view, the external affairs power apparently possesses. In R. v. Burgess; Ex parte Henry ("Burgess' Case") [26] a similarly wide view, described by Dixon J. [27] as extreme, had been expressed by Evatt and McTiernan JJ. but they confined their attention to the implementation of an international convention and saw the outer limits of the legislative power as being fixed by the requirement that any legislation passed pursuant to this power should represent the fulfilment, so far as possible, of all the obligations assumed under the convention. Moreover, they observed [28] that: Any departure from such a requirement would be completely destructive of the general scheme of the Commonwealth Constitution, for, as we are assuming for the moment, it is only because, and precisely so far as, the Commonwealth statute or regulations represent the carrying into local operation of the relevant portion of the international convention, that the Commonwealth Parliament or Executive can deal at all with the subject-matters of the convention. Doubtless this requirement does not necessarily preclude the exercise of wide powers and discretions by the Parliament or the Executive of the Commonwealth, for the international convention may itself contemplate that such powers and discretions should be exercisable by the appropriate authority of each party to the convention. Everything must depend upon the terms of the convention, and upon the rights and duties it confers and imposes. But the general requirement must be fulfilled or the Commonwealth will be exceeding its lawful domain. Upon this view everything must depend upon the terms of the convention or treaty and that, as will appear, is enough to decide this case. But if Evatt and McTiernan JJ. thought that this requirement provided any real limit to the reach of the external affairs power, then history has belied them. The precise terms of the convention for the regulation of aerial navigation, which was the treaty in question in Burgess' Case, are in stark contrast to those of the Convention for the Protection of the World Cultural and Natural Heritage which, in accordance with modern custom, give expression to broad policy, to aspiration and to exhortation. If actual obligations are imposed, they are of the most imprecise kind. And, of course, upon the view adopted by the majority in the Tasmanian Dam Case, the decisive thing must, in the end, be not the treaty but the international concern to which the treaty gives expression. 1. (1936) 55 C.L.R. 608. 2. (1936) 55 C.L.R., at p. 669. 3. (1936) 55 C.L.R., at p. 688. Doubtless it is convenient, and in many cases true, to say that the degree of international concern is accurately reflected in the treaty. And so, accepting the majority view in the Tasmanian Dam Case, it will, in many cases, be sufficient to establish the validity of legislation passed in pursuance of a treaty to say that it is within the contemplation of the treaty. The test to be applied may be expressed in various ways. The approach adopted by the majority in the Tasmanian Dam Case was that the legislation must be reasonably capable of being seen as appropriate and adapted to the purpose of giving effect to the treaty, the precise means adopted being a matter for Parliament. The element of purpose which is introduced by such a test is simply a means of establishing the necessary connexion between the legislation in question and the treaty which it purports to implement. The legislation if it is to be valid must be for the purpose of fulfilling the treaty. It is necessary to look at the purpose of the legislation to see whether it implements the treaty and so deals with a subject-matter which falls within the external affairs power, not for any purpose to be discerned from the legislative power itself. The legislative power is a power to legislate with respect to external affairs and the implementation of the treaty falls within that description not because of any purpose contained in it, but because the implementation of a treaty is a subject with a sufficient degree of externality to answer its requirements. This is reflected in the remarks of Dixon J. in Burgess' Case [29] when, in speaking of the obligation imposed by the convention for the regulation of aerial navigation, he said: It is apparent that the nature of this power necessitates a faithful pursuit of the purpose, namely, a carrying out of the external obligation, before it can support the imposition upon citizens of duties and disabilities which otherwise would be outside the power of the Commonwealth. No doubt the power includes the doing of anything reasonably incidental to the execution of the purpose. But wide departure from the purpose is not permissible, because under colour of carrying out an external obligation the Commonwealth cannot undertake the general regulation of the subject-matter to which it relates. The purpose to which he was referring was the purpose of fulfilling an obligation imposed by a treaty, not some purpose to be gleaned from the external affairs power. Dixon J. did not share the view of the majority in the Tasmanian Dam Case, his belief being that the legislative implementation of a treaty fell within the external affairs power only if it " bound the Commonwealth in reference to some matter indisputably international in character " [30] For Dixon J. the conclusion of a treaty did not of itself confer international character upon its subject-matter. 1. (1936) 55 C.L.R., at pp. 674-675. 2. (1936) 55 C.L.R., at p. 669. It has been said more than once that where legislation implements a treaty, it is the implementation of the treaty which is the subject-matter falling within the external affairs power rather than the subject-matter of the treaty. Thus Mason J. in the Tasmanian Dam Case rejected the notion that once Australia enters into a treaty Parliament may legislate with respect to the subject-matter of the treaty as if that subject-matter were a new and independent head of Commonwealth legislative power. He continued [31] : The law must conform to the treaty and carry its provisions into effect. The fact that the power may extend to the subject-matter of the treaty before it is made or adopted by Australia, because the subject-matter has become a matter of international concern to Australia, does not mean that Parliament may depart from the provisions of the treaty after it has been entered into by Australia and enact legislation which goes beyond the treaty or is inconsistent with it. I must confess that I have some difficulty with those remarks. I cannot see why, if it is international concern which gives a subject-matter the character to bring it within the description of external affairs, the conclusion of a limited treaty upon that subject-matter should place outside the external affairs power that part of the subject-matter which is beyond the limits of the treaty. Nor can I see why legislation passed with respect to a matter of international concern should no longer be legislation with respect to external affairs simply because Australia becomes a party to a treaty upon a more limited basis than is reflected by the legislation. 1. (1983) 158 C.L.R., at pp. 131-132. I suspect that the tendency to bring the focus back to the treaty stems from a desire to find practical limits to the ambit of the external affairs power lest the Court be seen to have relinquished in all but a theoretical sense the capacity to determine for itself the constitutional validity of legislation passed pursuant to that head of power. I think that a similar inclination lies behind the view that the external affairs power, like the defence power, is purposive in nature: see the Tasmanian Dam Case, per Deane J. [32] . 1. (1983) 158 C.L.R., at pp. 260-261. The purposive nature of the defence power, which differentiates it from other heads of power, including the external affairs power, makes it necessary to test the validity of a law passed in reliance upon it by reference to the purpose of the law rather than the subject-matter with which the law deals. Thus, at least in wartime, laws upon a vast number of matters, ranging from such things as capital loans and issues to housing and employment, may be brought within the defence power if it is necessary to do so for the purpose of defending the country. That is because the defence power contains within itself an expressed purpose, namely, the defence of the Commonwealth. It is necessary, because of the nature of that power, to look at what the legislation operates for, not what it operates upon: see Lane, Australian Federal System, 2nd ed. (1979), p. 139. And because conditions may vary from war to peace, what is necessary or appropriate for the defence of the Commonwealth may alter from time to time, giving the defence power an ambit which expands and contracts according to external conditions. Other powers, including the external affairs power, are different. The validity of legislation passed in reliance upon them is tested by reference to the subject-matter of the legislation: whether it falls within the description afforded by the head of power, either directly or incidentally. Thus, to take up the example which I used at the beginning of these reasons, a law will be a law with respect to interstate trade if it has a sufficient operation upon something forming part of interstate trade. Similarly, a law will be a law with respect to external affairs if it operates upon something forming part of the external affairs of the country. The implementation of treaties has been held to be such a thing and once a law can be seen to have been enacted in the implementation of a treaty, it will be held, upon the prevailing view, to be valid. The power to make laws with respect to external affairs contains no expression of purpose and in that respect it is like most of the other powers contained in s. 51 of the Constitution. It is not a power to make laws for the purpose of cementing international relations or achieving international goodwill or even for implementing international treaties. The implementation of treaties falls within the power because it is a subject-matter covered by the expression "external affairs". And the purpose of legislation which purports to implement a treaty is considered not to see whether it answers a requirement of purpose to be found in the head of power itself, but to see whether the legislation operates in fulfilment of the treaty and thus upon a subject which is an aspect of external affairs. If, as the majority in the Tasmanian Dam Case has held, it is international concern which ultimately marks out those matters which fall within the external affairs power, then it may be observed that that power also embraces a range of matters which may expand, and at least theoretically, contract from time to time. The application of the power will vary, not because the means necessary or appropriate to effectuate some purpose contained in the power change according to circumstances as is the case with a purposive power such as the defence power, but because a particular subject-matter may with the passage of time come to answer or cease to answer a description which brings it within the ambit of that power. It may also be observed that the power to implement a treaty may be wide or narrow according to the way in which the treaty is drawn. It is in that way that purpose enters into the exercise because what is appropriate for the purpose of giving effect to a treaty will depend upon how widely or narrowly the treaty is drawn. As Evatt and McTiernan JJ. observed in Burgess' Case, everything must depend upon the terms of the treaty and upon the rights and duties which it confers and imposes and the discretions which it creates. It is for this reason amongst others that the view taken of the external affairs power by the majority in the Tasmanian Dam Case may be described as expansive. The terms of the Convention for the Protection of the World Cultural and Natural Heritage reflect an evident desire to avoid encroachment upon the sovereignty of the nation states which are parties to the Convention. Each party is to determine for itself those measures which are appropriate for the identification and protection of the cultural and natural heritage within its territory. Indeed, if there is any significant obligation to be found in the Convention it must be that of devising and implementing those measures. The discretion reposed in the parties to the Convention to this end is absolute. Any suggestion that the legislation in question in this case goes further than is necessary is countered by the observation that the Convention leaves it to the parties, indeed upon one view imposes an obligation upon them, to decide for themselves what is necessary. The only possible question is whether the measures contained in the legislation are reasonably capable of being considered appropriate by the legislature for the identification and preservation of the nation's heritage and to answer that question in the negative would be tantamount to an imputation of mala fides. No such imputation has been made in this case. The Convention does not require proportionality between its aims and the measures taken to achieve them. That is a matter which is expressly left to the discretion of the parties. If the power thereby bestowed upon the legislature seems somewhat open-ended, it is not the result of any abdication by the Court of its role as an arbiter of constitutional validity but stems from the far-reaching view that a law which fulfils the provisions of a bona fide treaty, whatever they might be, is a law with respect to external affairs. For these reasons and upon the assumptions which I have made I think that the answer to the first question is that the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth is wholly valid. As Mason C.J. and Brennan J. point out, it is inappropriate, apart from pars (i) and (ii) to answer the second question in the absence of agreed facts and as Wilson J. points out, the question was not, in the end, really pressed. I would answer pars. (i) and (ii) in the same way as Mason C.J. and Brennan J. for the reasons which they give and would decline to answer the rest of that question. Toohey J. The defendants challenge the validity of the Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act"), in particular Pt III of the Act, as beyond the legislative competence of the Parliament of the Commonwealth. The long title of the statute describes it as: "An Act to provide for the establishment of the Commission of Inquiry into the Lemonthyme and Southern Forests, and for related purposes." The object of the legislation, as expressed by s. 4, is "to provide for measures that will enable effect to be given, in relation to the Lemonthyme area and the Southern Forests area, to Australia's obligations under the Convention, in particular the obligations to: (a) identify and delineate the natural heritage and cultural heritage; and (b) take appropriate measures to protect and conserve that heritage". The Convention referred to is the Convention for the Protection of the World Cultural and Natural Heritage, adopted by the General Conference of the United Nations Educational, Scientific and Cultural Organisation and to which Australia is party. It is given effect to by the World Heritage Properties Conservation Act 1983 Cth ("the World Heritage Act") to which it appears as a schedule. Part II of the Act establishes the Commission of Inquiry into the Lemonthyme and Southern Forests. The Commission is required to inquire into and report on certain matters. To appreciate the nature of the inquiry, regard must be had to the notion of "qualifying area". Section 3 of the Act defines "qualifying area" to mean so much of any area that is: (a) wholly or partly within the Lemonthyme area or the Southern Forests area; and (b) a world heritage area or an area that contributes to the integrity or values of: (i) a world heritage area that is wholly or partly within the Lemonthyme area or the Southern Forests area; or (ii) a nominated world heritage area; as is not a nominated world heritage area. The expression "world heritage area" is defined by s. 3 to mean: "an area that forms part of the cultural heritage or the natural heritage". Section 3 gives to "cultural heritage" and "natural heritage" the same meanings they have in the Convention. Section 8(1) requires the Commission to inquire into and report on: (a) whether there are any qualifying areas; (b) where there are qualifying areas: (i) whether there are, within areas of Tasmania that are outside the qualifying areas and are not national estate areas, forestry resources capable of exploitation in a way that would cause no detriment to the Tasmanian forestry industry and that would be an environmentally and economically prudent and feasible alternative to the exploitation of any forestry resources in the qualifying areas; (ii) where there are not — whether there are, within areas of Tasmania (including national estate areas other than nominated world heritage areas) that are outside the qualifying areas, forestry resources capable of exploitation in a way that would cause no detriment to the Tasmanian forestry industry and that would be an environmentally and economically prudent and feasible alternative to the exploitation of any forestry resources in the qualifying areas; and (iii) where there are not — which of the means of exploiting the forestry resources of Tasmania (including the qualifying areas but not including any nominated world heritage areas) without causing any detriment to the Tasmanian forestry industry will cause least damage to the qualifying areas; (c) where the first-mentioned forestry resources in subparagraph (b)(i) or (ii) are not capable of exploitation in the way referred to in that subparagraph, whether those forestry resources are capable of exploitation in ways that are environmentally and economically prudent and feasible alternatives to the exploitation of any forestry resources in the qualifying areas, and, if so, which of those ways will cause the least detriment to the Tasmanian forestry industry; (d) where the first-mentioned forestry resources in subparagraph (b)(ii) are capable of exploitation in the way referred to in that subparagraph, whether that exploitation, in so far as it affects national estate areas, is, consistent with proper forestry management, able to be delayed, and, if so, the extent of that delay; (e) where a means of exploiting the forestry resources of Tasmania that will cause least damage to any qualifying areas is identified under subparagraph (b)(iii), whether that exploitation, in so far as it affects either national estate areas or qualifying areas, or both, is, consistent with proper forestry management, able to be delayed, and, if so, the extent of that delay. The Commission is in the course of conducting its inquiry. The Lemonthyme and Southern Forests areas of Tasmania comprise 14,300 and 269,000 hectares respectively. Together they constitute about 4.5 per cent of Tasmania's land surface. They abut part of the eastern boundary of an area listed in the World Heritage List established under the Convention and known as the Western Tasmanian Wilderness National Parks. The land is almost entirely Crown land though there are small pockets of freehold. It is common ground that the areas contain substantial portions of State forest, some but not all of which is suitable for commercial exploitation. Part III of the Act is entitled Interim Protection of Certain Areas. To understand the operation of Pt III it is again necessary to resort to the definition section of the Act. (The Act is very much its own dictionary though some of its expressions derive from the Convention.) Section 3 defines "protected area" to mean "the Lemonthyme area and the Southern Forests area, other than any part of either area that is an excluded area". An "excluded area" is one specified in a notice under s. 20(a)(i) of the Act, a reference to a notice to be published in the Gazette by the Minister on receipt of an interim report from the Commission. The sting of Pt III lies in s. 16, sub-s. (1) of which reads: Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, to do any of the following acts during the interim protection period: (a) for the purposes of, or in the course of carrying out, forestry operations, to kill, cut down or damage a tree in, or remove a tree or a part of a tree from, the protected area; (b) to construct or establish a road or vehicular track within the protected area; (c) to carry out any excavation works within the protected area; (d) to do any other act prescribed for the purposes of this paragraph, being an act capable of adversely affecting the protected area. The "interim protection period" referred to in s. 16 is defined by s. 3 to mean: the period commencing at the commencement of the inquiry period and ending at the end of the forty-second day after: (a) where paragraph (b) does not apply — the end of the inquiry period; or (b) where, before the last day of the inquiry period, notice of the receipt by the Minister of the final report is published in the Gazette under subparagraph 20(a)(ii) — the day on which that notice is published. In determining whether or not to give a consent under s. 16, the Minister "shall have regard only to Australia's obligations under the Convention": s. 18(1). The attack on the validity of the Act is made in the context of an application by the federal Minister of State for the Environment and the Arts to restrain the first defendant, a body established by the Forestry Act 1920 Tas. to control and manage forests in Tasmania, and the second defendant, a timber miller, from continuing logging operations within the protected area. The logging operations planned for the interim protection period involve 145 ha. in the Lemonthyme area and 151 ha. in the Southern Forests area, in both cases with associated road-works. The basis of the attack on the Act lies in the fact that no part of the protected area is "identified property" as that term is defined in the World Heritage Act. Section 3(2) of this Act provides that a reference to identified property is a reference to: (a) property forming part of the cultural heritage or natural heritage, being property that— (i) the Commonwealth has, under Article 11 of the Convention, submitted to the World Heritage Committee as suitable for inclusion in the World Heritage List ; or (ii) has been declared by the regulations to form part of the cultural heritage or natural heritage; or (b) any part of property referred to in paragraph (a). At the time of the hearing of this matter Australia had not sought inclusion in the World Heritage List, whether as part of the Western Tasmanian Wilderness National Parks or otherwise, of either the Lemonthyme or Southern Forests. By requiring the Commission to give priority to identifying any part or parts of the areas "that are definitely not qualifying areas" and reporting to the Minister accordingly (s. 8(5)), the Act contemplates that there will be parts, perhaps substantial parts, that will not meet the criteria for cultural or natural heritage in the Convention. The question of construction posed by the defendants is whether Australia has any obligations under the Convention in respect of the Lemonthyme and Southern Forests, having regard to the absence of those areas from the World Heritage List, indeed from nomination to that list. Articles 1 and 2 of the Convention define what is meant by cultural heritage and natural heritage. Article 3 asserts: It is for each State Party to this Convention to identify and delineate the different properties situated on its territory . By Art. 4 each State Party to the Convention: recognizes that the duty of ensuring the identification, protection, conservation, presentation and transmission to future generations of the cultural and natural heritage referred to in Articles 1 and 2 and situated on its territory, belongs primarily to that State. Article 5 spells out the measures to be taken by a State Party to the Convention "for the protection, conservation and presentation" of its cultural and natural heritage. These include: (d) to take the appropriate legal, scientific, technical, administrative and financial measures necessary for the identification, protection, conservation, presentation and rehabilitation of this heritage. The attack on the Act focuses largely on Pt III, the argument being that, on no view of Australia's obligations under the Convention and the scope of s. 51(xxix) of the Constitution, can the prohibitions in s. 16 of the Act be justified. And, it is said by the defendants, the conduct proscribed by s. 16 includes conduct that may in no way infringe any of the values sought to be protected by the Convention. By way of illustration, the building of a fire-break might constitute "excavation works" and fall foul of par. (c) of s. 16(1), though the fire-break would serve to protect the forest. The defendants further argue that, if the consent of the Minister is sought to such conduct, the Minister may have regard only to Australia's obligations under the Convention, obligations which may have little relevance to the circumstances in which consent is sought. The Convention imposes an obligation on Australia as a State Party to the Convention to ensure that effective and active measures are taken for the protection, conservation, presentation and transmission to future generations of its cultural and natural heritage, including the taking of legal measures to this end: The Commonwealth v. Tasmania ("the Tasmanian Dam Case "), per Mason J. [33] , per Murphy J. [34] , per Brennan J. [35] and per Deane J. [36] . That is sufficient, though not necessary, to bring such measures within the external affairs power of the Constitution: s. 51(xxix). Furthermore the implementation of the Convention is, independently of a specific obligation to do so, an exercise of the external affairs power: the Tasmanian Dam Case, per Mason J. [37] , per Brennan J. [38] and per Deane J. [39] . None of the parties sought to re-argue the decision in that case. 1. (1983) 158 C.L.R. 1, at pp. 132-136. 2. (1983) 158 C.L.R., at pp. 177-178. 3. (1958) 158 C.L.R., at pp. 216-228. 4. (1983) C.L.R., at pp. 253-254, 261-264. 5. (1983) 158 C.L.R., at pp. 129-130. 6. (1983) 158 C.L.R., at p. 226. 7. (1983) 158 C.L.R., at pp. 258-259. Part II of the Act sets up machinery to identify areas that will answer the description of world heritage areas or areas contributing to the integrity or values of world heritage areas. In that way it gives effect to Arts. 3 and 4 of the Convention. But the defendants contend that Pt III of the Act cannot be supported in this way. Except with the consent of the Minister, the conduct set out in s. 16 is proscribed. This proscription is said to be beyond any view of the external affairs power, for two reasons. The first is that it relates to the protected area, meaning the Lemonthyme and Southern Forests (other than an excluded area). And, so the argument runs, there is no necessary correspondence between the protected area and a qualifying area. It may well turn out that little or none of the protected area answers the description of a qualifying area. Nevertheless, during the interim protection period any conduct falling within s. 16 of the Act may be restrained unless the Minister consents to it. Secondly, say the defendants, the conduct proscribed by s. 16 may have no relation to the protection, conservation or presentation of the cultural and national heritage that the Convention aims to save. Such conduct may be neutral in that regard or may positively assist preservation, conservation or presentation of the heritage but be proscribed, either expressly in terms of pars. (a), (b) or (c) or through the operation of par. (d). The Tasmanian Dam Case was of course concerned with land that was on the World Heritage List. None of the Lemonthyme or Southern Forests is on that list. Article 11 of the Convention prescribes the procedure by which property may be included in the list. In effect a State Party to the Convention submits an inventory of property forming part of its cultural and natural heritage. The World Heritage Committee established by the Convention determines whether or not property should be included in the list. It is for each State Party to the Convention to identify and delineate the different properties on its territory constituting its cultural or natural heritage: Art. 3. The role of identification is reinforced by Arts. 4 and 5. The obligations imposed by Art. 5, especially those nominated in par. (d), make it clear that identification is an integral part of the protection of the cultural and natural heritage: see also the Tasmanian Dam Case, per Mason J. [40] and per Brennan J. [41] . 1. (1983) 158 C.L.R., at p. 133. 2. (1983) 158 C.L.R., at p. 228. Counsel for the State of Queensland, an intervener, submitted that the process contemplated by the Convention is identification, then protection. In consequence, it was argued, Pt III of the Act could only be justified if reasonably necessary for the step of identification for, in the absence of identification, it could not be supported as a measure for protection or conservation. This is an unduly narrow view of what the Convention demands. Identification and protection of the cultural and natural heritage do not form discrete compartments nor is there a pre-ordained sequence as between them. And it is significant that Art. 4 of the Convention contains a recognition that it is the duty of each State Party to the Convention to ensure identification and protection. As Mason J. pointed out in the Tasmanian Dam Case [42] : Implementation of the Convention, and of the obligation which it imposes on Australia in relation to the property, calls for the establishment of a regime of control which will ensure protection and conservation of the property. No doubt there are a variety of methods of control which will achieve this result. But it is not for the Court to choose between them, or to prefer one to another. The only question is whether the legislative provisions are appropriate and adapted to the desired end . 1. (1983) 158 C.L.R., at p. 138. The power conferred on the Parliament by s. 51(xxix) is a power to legislate "with respect to" external affairs. What those words require is "a relevance to or connexion with the subject assigned to the Commonwealth Parliament": Grannall v. Marrickville Margarine Pty. Ltd. [43] . The Court continued in Grannall [43] : every legislative power carries with it authority to legislate in relation to acts, matters and things the control of which is found necessary to effectuate its main purpose, and thus carries with it power to make laws governing or affecting many matters that are incidental or ancillary to the subject-matter. 1. (1955) 93 C.L.R. 55, at p. 77. 2. (1955) 93 C.L.R. 55, at p. 77. To return to the Act itself. As mentioned earlier, s. 4 expresses the object of the Act as. "to provide for measures that will enable effect to be given, in relation to the Lemonthyme area and the Southern Forests area, to Australia's obligations under the Convention ". In its language, the section appropriately accommodates the object of the Convention. It is not the Commission's inquiry that is under attack. Indeed no specific head of power is necessary to enable the Commonwealth to conduct an inquiry. It is the use of compulsion and the imposition of prohibitions on conduct that give rise to questions of power: Clough v. Leahy [44] ; Lockwood v. The Commonwealth [45] ; Church of Scientology v. Woodward [1] . 1. (1904) 2 C.L.R. 139. 2. (1954) 90 C.L.R. 177, at p. 182. 3. (1982) 154 C.L.R. 25, at p. 62. Part III of the Act is expressly limited in the duration of its operation. The interim protection period mentioned in s. 16 has already been referred to and its connexion with the duration of the inquiry noted. Given the complexity of the Commission's inquiry, the period cannot be regarded as unreasonable. The acts prohibited by s. 16 are identified in general terms, but with sufficient clarity. They are acts of a nature calculated to have an adverse effect on the wilderness area that is said to constitute the natural or cultural heritage, even though it is not hard to conceive of a prohibited act that may, in some circumstances, not endanger the environment. (The building of a fire-break has already been mentioned in this context.) Though par. (d) of s. 16(1) includes among the prohibited acts "any other act prescribed for the purposes of this paragraph", such an act must be "capable of adversely affecting the protected area". In determining whether or not to give a consent under s. 16, the Minister "shall have regard only to Australia's obligations under the Convention": s. 18. I do not accept the submission of the defendants that the limitation on the matters the Minister may take into account in some way takes s. 16 beyond a legitimate exercise of power. Indeed it is apparent that the protection and conservation of property, in this case the particular forest areas, circumscribes the range of matters to be taken into account by the Minister when deciding whether or not to give a consent under s. 16. A refusal based on other considerations would not be a legitimate exercise of power. An act which falls within pars. (a), (b) or (c) of s. 16(1) but which, in the particular circumstances, is not likely to be destructive of the heritage is an act to which the Minister may give his consent, consistently with Australia's obligations under the Convention. No doubt a refusal of ministerial consent may, in a particular case, cause hardship to an applicant. But s. 19 of the Act imposes a liability on the Commonwealth to pay compensation to a person who suffers loss or damage because he refrains from doing an act made unlawful by s. 16(1). Equally, where the owner of any part of the protected area suffers loss or damage because another person refrains from doing an act made unlawful by s. 16(1), there is a liability on the Commonwealth to pay compensation. Furthermore, a decision by the Minister to grant or withhold consent is susceptible of review under the provisions of the Administrative Decisions (Judicial Review) Act 1977 Cth and in the exercise of the original jurisdiction of this Court and the Federal Court, under s. 75(v) of the Constitution and s. 39B of the Judiciary Act 1903 Cth respectively. Part III is aimed at insulating the protected area from acts that may adversely affect it, but only for the duration of the inquiry. If Pt III was of indefinite duration, a serious question would arise as to its connexion with the obligations of Australia under the Convention. But its life is limited, governed by the life of the inquiry which has as its object the identification of areas that form part of the natural and cultural heritage of this country. It applies only to the protected area; furthermore s. 8(5) of the Act obliges the Commission to give priority to identifying any parts of the areas "that are definitely not qualifying areas" and to report accordingly to the Minister "as soon as practicable". The consequence of such a report is that the area in question becomes an "excluded area" and no longer relevantly part of the Lemonthyme area or Southern Forests area. Overall there is a close connexion between the prohibition in s. 16 and the process of identification and protection in the Convention. The considerations which I have mentioned in regard to s. 16 and Pt III generally distinguish and render inapplicable the reasons that lead Brennan J. and Deane J. to strike down s. 9(1)(a) to (g) of the World Heritage Act in the Tasmanian Dam Case. Thus the Act is consistent with and gives effect to Australia's obligations under the Convention. It is, in the language of Barwick C.J. in Airlines of N.S.W. Pty. Ltd. v. New South Wales [No. 2] [2] , "appropriate and adapted" to the implementation of the Convention. Certainly it is seen by the Parliament to be so; viewed objectively it is capable of being reasonably considered to be so and that is enough to support the means chosen by Parliament to give effect to the Convention: the Tasmanian Dam Case, per Mason J. [3] , per Murphy J. [4] , per Brennan J. [5] , and per Deane J. [6] . The absence of areas from the World Heritage List is no obstacle to the validity of the Act, for the Act constitutes a scheme designed to identify areas that warrant protection under the Convention by their inclusion on the list. 1. (1965) 113 C.L.R. 54, at p. 86. 2. (1983) 158 C.L.R., at pp. 130-132. 3. (1983) 158 C.L.R., at p. 172. 4. (1983) 158 C.L.R., at p. 232. 5. (1983) 158 C.L.R., at pp. 259-261. Equally, the inclusion in the definition of "qualifying area" of land that is not itself a world heritage area but contributes to the integrity or values of such an area cannot invalidate the Act. It may fairly be seen as an aspect of the Commission's inquiry under s. 8 of the Act, designed to assist Australia in its obligations under the Convention to identify and delineate the world heritage that may exist within the Lemonthyme and Southern Forests areas and also to protect that heritage from damaging activities on adjacent land. The defendants make the further point that the Act, in particular Pt III, is invalid because it curtails or impairs the legislative and executive functions of the State of Tasmania and the prerogative of the Crown in right of Tasmania in relation to its lands. But nothing in the Act discriminates against Tasmania as a member of the federation. The Act fastens on to an area of land that, as it happens, is part of Tasmania. But it does so because of the character of that area of land, not because it is part of a particular State. Nor does the Act hinder or impair the continued existence of Tasmania or its capacity to function. The most that can be said is that for a limited time there is a prohibition against certain conduct on the land to which the Act relates: cf. the Tasmanian Dam Case, per Mason J. [7] , per Murphy J. [8] , per Brennan J. [9] and per Deane J. [10] . The argument must fail. 1. (1983) 158 C.L.R., at pp. 139-141. 2. (1983) 158 C.L.R., at pp. 168-170. 3. (1983) 158 C.L.R., at pp. 215-216. 4. (1983) 158 C.L.R., at pp. 280-281. There is a further question reserved for consideration by the Full Court. It is in these terms: In point of law is any, and if so, which, of the allegations made: (i) in par. 17 of the Defence of the First Defendant (ii) in par. 15 of the Defence of the Second Defendant (iii) in par. 16 of the Defence of the Second Defendant, an answer to the relief claimed by the Plaintiff against the respective Defendants? This question and its implications are examined by Mason C.J. and Brennan J. with whose conclusions I agree. Accordingly I agree with the answers proposed by them. Gaudron J. Australia is a State Party to the Convention for the Protection of the World Cultural and Natural Heritage adopted by the General Conference of the United Nations Educational, Scientific and Cultural Organization ("the Convention") in 1972. The Lemonthyme and Southern Forests (Commission of Inquiry) Act 1987 Cth ("the Act") has as its stated object in s. 4 the provision for measures to enable effect to be given to Australia's obligations under the Convention in relation to the Lemonthyme and Southern Forests areas of Tasmania. The primary obligations imposed upon each State Party to the Convention are to identify and delineate the cultural and natural heritage as defined in the Convention, and to protect, conserve, present and transmit that heritage to future generations: Arts. 3 and 4. These obligations are amplified in Art. 5 to include the duty to: endeavour, in so far as possible, and as appropriate for each country: (d) to take the appropriate legal, scientific, technical, administrative and financial measures necessary for the identification, protection, conservation, presentation and rehabilitation of [the] heritage. "Cultural heritage" is defined in Art. 1 to include: elements or structures of an archaeological nature, inscriptions, cave dwellings and combinations of features, which are of outstanding universal value from the point of view of history, art or science; [and] sites: works of man or the combined works of nature and of man, and areas including archaeological sites which are of outstanding universal value from the historical, aesthetic, ethnological or anthropological points of view. No other part of the definition would seem applicable to the Lemonthyme and Southern Forests areas. These consist mainly of wilderness and forest, although they have 155 ha. and 80 ha. respectively in private ownership and used for grazing. "Natural heritage" is defined in Art. 2 as: natural features consisting of physical and biological formations or groups of such formations, which are of outstanding universal value from the aesthetic or scientific point of view; geological and physiographical formations and precisely delineated areas which constitute the habitat of threatened species of animals and plants of outstanding universal value from the point of view of science or conservation; natural sites or precisely delineated natural areas of outstanding universal value from the point of view of science, conservation or natural beauty. The Act establishes a Commission of Inquiry ("the Commission") which by s. 8(1)(a) is required to inquire and report whether there are any qualifying areas, which are defined in s. 3 to mean so much of an area that is: (a) wholly or partly within the Lemonthyme area or the Southern Forests area; and (b) a world heritage area or an area that contributes to the integrity or values of: (i) a world heritage area that is wholly or partly within the Lemonthyme area or the Southern Forests area; or (ii) a nominated world heritage area; as is not a nominated world heritage area. Where there are qualifying areas, the Commission is also required to inquire and report as to forestry resources in Tasmania, and in particular to determine whether there are any such resources outside a qualifying area which might be exploited without detriment to the forestry industry in Tasmania as an alternative to the forestry resources in any areas found to be qualifying areas: s. 8(1)(b). The Commission is also to inquire and report on various matters concerning the possible exploitation of forestry resources in Tasmania. Section 8(5) directs the Commission to give priority to identifying any parts of the Lemonthyme or Southern Forests areas that are definitely not qualifying areas and report the identification of any such part or parts to the Minister as soon as practicable. Section 16 falls within Pt III of the Act, and accords protection to the Lemonthyme and Southern Forests areas for an "interim protection period" which is defined in s. 3 of the Act as: the period commencing at the commencement of the inquiry period and ending at the end of the forty-second day after: (a) where paragraph (b) does not apply — the end of the inquiry period; or (b) where, before the last day of the inquiry period, notice of the receipt by the Minister of the final report is published in the Gazette under subparagraph 20(a)(ii) — the day on which that notice is published. "Inquiry period" is defined as the period commencing when the Act comes into operation and ending one year afterwards. The protection afforded by s. 16 ceases in respect of any area identified by the Commission under s. 8(5) as definitely not a qualifying area upon publication of notice in the Gazette of the area thus identified: see definitions of protected area and excluded area in s. 3 of the Act. In accordance with s. 20(a)(i), a notice specifying the area identified as definitely not a qualifying area must be published within fourteen days of the Minister's receipt of the report. Section 16 provides: (1) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, to do any of the following acts during the interim protection period: (a) for the purposes of, or in the course of carrying out, forestry operations, to kill, cut down or damage a tree in, or remove a tree or a part of a tree from, the protected area; (b) to construct or establish a road or vehicular track within the protected area; (c) to carry out any excavation works within the protected area; (d) to do any other act prescribed for the purposes of this paragraph, being an act capable of adversely affecting the protected area. (2) Except with the consent in writing of the Minister, it is unlawful for a person, whether personally or through a servant or agent, during the interim protection period to permit, authorise, direct or order or to purport to permit, authorise, direct or order any person to do an act that is unlawful under subsection (1). (3) Except with the consent of the Minister, it is unlawful for a person who is the owner or occupier of any part of the protected area to fail to take reasonable steps to prevent the doing within that part of the protected area of any act that is unlawful under subsection (1). Section 18 requires the Minister, when determining whether or not to consent to any act otherwise forbidden by s. 16, to have regard only to Australia's obligations under the Convention. The first question asked in the present case stated is to what extent, if any, is the Act invalid. In the course of argument the area of contest was narrowed to two issues, namely, the validity of the Act in so far as it authorises inquiry as to available forestry resources and alternatives to the exploitation of forest resources in a qualifying area, and the validity of Pt III (which includes ss. 16 and 18) and which may be described as the protective provisions of the Act. The questions arise in a context somewhat different from that which provided the background to the decision in The Commonwealth v. Tasmania ("the Tasmanian Dam Case ") [11] . The legislation there under consideration was challenged with respect to its operation on land which had been identified and delineated as forming part of the cultural or natural heritage the subject of the Convention. It was not in issue that the land so identified and delineated constituted part of the natural heritage as defined in the Convention. It was in that case decided that the Convention gave rise to an obligation with respect to that land and that the legislation, so far as it was held valid, was legislation which implemented that obligation. 1. (1983) 158 C.L.R. 1. The Lemonthyme and Southern Forests areas may, or may not be, or contain, areas of "outstanding universal value". Although s. 4 of the Act speaks of Australia's obligations under the Convention in relation to the Lemonthyme and Southern Forests areas, the Act is not accurately described as one which implements an obligation under the Convention attaching to those areas. Rather, the Act provides the machinery to determine whether there is a Convention obligation in respect of the areas (or part thereof); to determine, in other words, whether any of the areas to which the Commission's attention is directed are part of the heritage to which the Convention applies. It is not necessary that an area be identified or delineated, much less nominated or accepted for inclusion on the World Heritage List, for it to constitute part of the heritage to which the Convention applies. However, where the legislation under consideration posits no more than that an area may consist of (or contain) a world heritage area, or an area may contribute to the integrity or values of a world heritage area (leaving open the possibility that it may contain neither) and the purpose of the legislation is to ascertain whether and, if so, where there are such areas, it is not then possible to assert the existence of a recognizable obligation under the Convention attaching to the relevant area as a heritage area. The absence of a recognizable obligation attaching to the Lemonthyme and Southern Forests areas as heritage areas is not necessarily fatal to the validity of s. 16. However, the question of validity must be answered by reference to other considerations, for the Court cannot uphold the validity of a law by reference to the existence of some fact or state of affairs unless satisfied of the existence of that fact or state of affairs: Australian Communist Party v. The Commonwealth [12] ; Commonwealth Freighters Pty. Ltd. v. Sneddon [13] ; Hughes and Vale Pty. Ltd. v. New South Wales [No. 2] [14] . In satisfying itself on the validity of an enactment, the Court may make "every reasonable intendment" in favour of the legislation: Attorney-General (Vict.) v. The Commonwealth [15] . However, given the uncertainty manifest in the Act as to whether or not any area within the Lemonthyme or Southern Forests areas is a world heritage area or contributes to the integrity or values of a world heritage area, no reasonable intendment in favour of the legislation can be made by reference to any Convention obligation attaching to the areas as heritage areas. 1. (1951) 83 C.L.R. 1, at p. 222. 2. (1959) 102 C.L.R. 280, at p. 307. 3. (1955) 93 C.L.R. 127, at p. 165. 4. (1945) 71 C.L.R. 237, at p. 267. The Tasmanian Dam Case established that a treaty obligation will attract the legislative power of the Commonwealth with respect to external affairs. In that case the majority also gave expression to the view, which I would adopt, that the power may be attracted by a treaty notwithstanding the absence of a treaty obligation. Mason J. [16] observed: If the carrying out of, or the giving effect to, a treaty or convention to which Australia is a party is a matter of external affairs, and so much is now accepted, it is very difficult to see why a law made under s. 51(xxix), i.e., a law with respect to the matter of external affairs, should be limited to the implementation of an obligation. 1. (1983) 158 C.L.R., at pp. 129-130. Murphy J. [17] was of the view that it was sufficient if the law inter alia: (b) implements any treaty or convention whether general (multilateral) or particular, or (c) implements any recommendation or request of the United Nations organization or subsidiary organizations such as the World Health Organization, the United Nations Education, Scientific and Cultural Organization, the Food and Agriculture Organization or the International Labour Organization . 1. (1983) 158 C.L.R., at pp. 171-172. Brennan J. stated [18] : I should wish to guard against a suggestion that it is necessary to find such an obligation before one can find an external affair which enlivens the power under s. 51(xxix). 1. (1983) 158 C.L.R., at p. 222. Deane J. [19] said: It is, however, relevant for present purposes to note that the responsible conduct of external affairs in today's world will, on occasion, require observance of the spirit as well as the letter of international agreements, compliance with recommendations of international agencies and pursuit of international objectives which cannot be measured in terms of binding obligation. 1. (1983) 158 C.L.R., at pp. 258-259. I am of the view that it is not necessary for a treaty to which Australia is a party to impose an obligation upon Australia as a condition precedent to engaging the external affairs power. The fact that Australia is a party to a treaty (leaving to one side a treaty which is not entered into bona fide) will itself suffice to engage the power to legislate with respect to external affairs, and will authorize the passing of a law so long as that law is reasonably capable of being viewed as conducive to the purpose of the treaty if it is also reasonably capable of being viewed as appropriate, or adapted to, the circumstance which engages the power. On the view I adopt it is not necessary for the validity of the Act that there be isolated a Convention obligation with respect to property which may or may not be a world heritage area. However, even if the validity of the Act was to turn upon identifying such a Convention obligation, I am of the view that the Convention obligation in Art. 2 to identify and delineate, and the obligation in Art. 5(d) to take appropriate measures for the identification of world heritage areas, have implicit in them an obligation to take appropriate steps to protect and conserve the features which give to property the quality that it may be part of the world heritage pending a determination as to whether or not it is part of that heritage. To determine whether the disputed provisions of the Act are reasonably capable of being considered conducive to the purpose of the Convention it is, I think, appropriate to accept the legislative judgment that there is a possibility that the areas consist of, or contain, parts which are of world heritage significance. Certainly that judgment is borne out by the non-disputed facts as set forth in the judgment of Mason C.J. which was delivered when granting interlocutory injunctions pursuant to s. 17 of the Act. The purpose of the Convention may briefly be described as the effective protection of the world cultural and natural heritage through measures taken by State Parties to the Convention, supported and assisted, where necessary, by other members of the international community. So much is able to be discerned from the scheme of the Convention, and in particular from Art. 7, which provides: For the purpose of this Convention, international protection of the world cultural and natural heritage shall be understood to mean the establishment of a system of international cooperation and assistance designed to support State Parties to the Convention in their efforts to conserve and identify that heritage. Each State Party undertakes obligations with respect to the identification, protection, conservation, presentation and transmission to future generations of the heritage in its territory, although Art. 5 provides that the active measures required of each State Party in relation to protection, conservation and presentation are those which are possible and appropriate for that country. Given that it is possible that the Lemonthyme and Southern Forests areas are, or contain areas which are, of world heritage significance, and that they also contain timbered areas which are the subject of permits for forestry operations, the ascertainment of the existence and exploitability of forest resources in Tasmania (whether within or without the Lemonthyme or Southern Forests areas) cannot be said to be irrelevant to a consideration of what is possible or appropriate in the event that the areas prove to be, or contain parts, of world heritage significance. Such an inquiry is, in my opinion, capable of being viewed as conducive to the purpose of the Convention, and is capable of being so viewed notwithstanding that it proceeds contemporaneously with the inquiry as to whether or not any part (or parts) of the areas are of world heritage significance. Once it is accepted that the question of validity may be answered by reference to the purpose of the Convention and not merely by reference to whether or not the land or property to which the law applies is part of the heritage as defined in the Convention, it must be accepted, in my view, that the legislative power extends, at once, to all matters conducive to that purpose. To allow that the legislative power extends, at once, to all matters conducive to the purpose of the Convention is to allow that the power extends to a law for the protection or conservation of those features which give to a property the quality that it might possess world heritage significance, at least for such time as is reasonably appropriate for the determination of that issue. If it is established that the property does have the necessary significance, legislative power extends to a law for the protection of the property for such time as is necessary for the determination of what is possible or appropriate in implementation of the Convention in relation to that property. It is established by the Tasmanian Dam Case that where Parliament enacts legislation in implementation of a treaty it is for the Parliament to choose the method by which that object is achieved, provided the method chosen is appropriate and adapted to that object. So too, it seems to me, that where the Parliament enacts legislation for the purpose of bringing about a state of affairs conducive to the purpose of a treaty, it is for the Parliament to choose the method by which that object is to be achieved. However, I do not think that it states the position with sufficient accuracy to say that a law which is enacted for the purpose of bringing about a state of affairs conducive to the purpose of a treaty must be appropriate and adapted to that object. It is clear from the Tasmanian Dam Case that the mere fact that Australia is party to a treaty does not engage the external affairs power so as to authorize a law on the subject covered by the treaty. The power is relevantly confined by the treaty. Mason J. put the matter thus [20] : I reject the notion that once Australia enters into a treaty Parliament may legislate with respect to the subject-matter of the treaty as if that subject-matter were a new and independent head of Commonwealth legislative power. The law must conform to the treaty and carry its provisions into effect. Murphy J. said [21] : The fact that a subject becomes part of external affairs does not mean that the subject becomes, as it were, a separate, plenary head of legislative power. If the only basis upon which a subject becomes part of external affairs is a treaty, then the legislative power is confined to what may reasonably be regarded as appropriate for implementation of provisions of the treaty. Again, if the subject of external affairs is some other circumstance, the legislative power will extend to laws which could reasonably be regarded as appropriate for dealing with that circumstance. Brennan J. observed [22] : The scope of the legislative power is defined by the international obligation and the validity of a law made in purported pursuance of the power depends upon whether "the law can fairly be regarded as providing a way of doing what the Commonwealth has undertaken to do; the choice of ways and means being a matter essentially for the Parliament": per Menzies J. in the Second Airlines Case [23] . Deane J. said [24] : the law must be capable of being reasonably considered to be appropriate and adapted to achieving what is said to impress it with the character of a law with respect to external affairs. See also R. v. Burgess; Ex parte Henry [25] ; R. v. Poole; Ex parte Henry [No. 2] [26] and Airlines of New South Wales Pty. Ltd. v. New South Wales [No. 2] [27] . 1. (1983) 158 C.L.R., at p. 131. 2. (1983) 158 C.L.R., at p. 172. 3. (1983) 158 C.L.R., at p. 232. 4. (1965) 113 C.L.R., at p. 136. 5. (1983) 158 C.L.R., at p. 259. 6. (1936) 55 C.L.R. 608, at pp. 659-660. 7. (1939) 61 C.L.R. 634, at p. 647. 8. (1965) 113 C.L.R. 54, at p. 86. The need for legislation which is enacted in discharge of a treaty obligation to conform to, or to be reasonably capable of being regarded as appropriate or adapted to, the treaty obligation derives not from any particular feature attaching to a treaty or treaty obligation, but rather, from the fact that the treaty obligation is the circumstance which engages the power to legislate with respect to external affairs. Where a law is enacted other than in discharge of a treaty obligation, the touchstone of validity must also be the circumstance which engages the external affairs power: i.e., "[t]he law must be seen, with "reasonable clearness", upon consideration of its operation, to be "really, and not fancifully, colourably, or ostensibly, referable" to and explicable by the purpose or object which is said to provide its character" per Deane J., the Tasmanian Dam Case [28] . 1. (1983) 158 C.L.R., at p. 260. In the present case, whether the question of legislative power be approached in terms of an obligation implicit in the Convention to take appropriate steps to protect the features which give to property the quality that it may form part of the world heritage, or whether it be approached in terms of securing a state of affairs conducive to the purposes of the Convention, at base the circumstance that engages the legislative power is that the Lemonthyme and Southern Forests areas may be (or may contain) world heritage areas. It is to that circumstance, comprehending the possibility that the areas, either in whole or in part, may lack world heritage significance, that the law must be appropriate and adapted. Within the context of the Convention, a law which provides machinery to investigate and determine whether land is, or contains, a world heritage area, and which further provides for a determination of matters relevant as to what is appropriate or possible in discharging obligations arising under the Convention in relation to any land so found, is appropriate and adapted to the circumstance that the land identified in the preamble to the Act may be, or may contain, areas of world heritage significance. Accordingly, in my view, s. 8 of the Act is valid. Within that same context, a law which protects and conserves the qualities or features which give to the land the characteristic that it may be, or contain, a world heritage area, will also be appropriate and adapted to the circumstance which, at base, engages the power to legislate with respect to external affairs. A law which does more lacks proportionality to that circumstance, for as Deane J. observed in the Tasmanian Dam Case [28] , there is "[i]mplicit in the requirement that a law be capable of being reasonably considered to be appropriate and adapted to achieving what is said to provide it with the character of a law with respect to external affairs a reasonable proportionality between the designated purpose or object and the means which the law embodies for achieving or procuring it". A law, therefore, which proscribes activities which pose no threat to the qualities or features which give the land the characteristic that it may be, or may contain, a world heritage area, is not one which (in the context of the Convention) can be said to be a law with respect to external affairs. 1. (1983) 158 C.L.R., at p. 260. In the present case no effort was made to identify the qualities or features giving the land its relevant characteristic beyond those identified in the judgment of Mason C.J. when granting interlocutory relief under the Act. Those so identified include stands of wet sclerophyll forest, a stand of timber containing King Billy pine, communities of Alpine plants, an area of Huon pine, and wilderness areas in the Southern Forests area [29] . In the Lemonthyme, the identified features include areas of tall eucalypt and possibly archaeological sites. It may be accepted that forestry operations, construction of roads or vehicular tracks, or excavation works, which are rendered unlawful by s. 16(1)(a), (b) and (c), constitute a threat to the features identified, if undertaken in, or in proximity to the specific areas in which they are located. However, the proscriptions apply generally, save to the extent that any area is identified as definitely not a qualifying area. They apply to areas of land in private ownership and used for grazing. They apply also to an area in which timber has been felled and to an area that has been previously cut over. There is no material which enables it to be said that each and every act proscribed by s. 16(1)(a), (b) or (c) would, if done in the protected area, constitute a danger to the qualities and features which are relevant to the Lemonthyme and Southern Forests areas as areas which are possibly of world heritage significance. The fact that the areas contain grazing land and an area in which timber has been felled and an area which has been cut over suggests otherwise. In the absence of material to the contrary, s. 16(1)(a), (b) and (c) must be viewed as operating to curtail activities whether or not they constitute a threat to the relevant qualities or features of the area. That is, they must be viewed as operating to protect the general environment of the area, and not merely the features which may be of outstanding universal value within the contemplation of the Convention. With s. 16(1)(d) the legal criterion upon which it is posited is general environmental protection, for it renders unlawful any act "prescribed for the purposes of this paragraph, being an act capable of adversely affecting the protected area " (emphasis added). The same general environmental protection is extended by s. 16(2) and (3) by rendering unlawful the actions of permitting, authorizing, directing or ordering any act which is unlawful under sub-s. (1) (except with the consent of the Minister) and in the case of an owner or occupier of land, the failure to take reasonable steps to prevent the doing of any act proscribed by s. 16(1). 1. Ante, pp. 272-273. Because s. 16 must be viewed as affording general environmental protection rather than protection of the qualities and features which may be of outstanding universal value, it is not on the material before the Court reasonably capable of being viewed as appropriate or adapted to the circumstance that the areas may be or contain areas constituting part of the world heritage. It cannot on the available material be characterized as a law with respect to external affairs. Nor, in my view, is that conclusion altered by the possibility that the proscription may be relaxed with the consent of the Minister. By s. 18 the Minister's consent to an act otherwise unlawful is to be given or withheld having "regard only to Australia's obligations under the Convention". The criterion for the giving or withholding of consent appears to me to lack clarity. Clearly, s. 18 would require the granting of consent to an act necessary or desirable for the protection of qualities or features which give the land the characteristic that it may be or contain a world heritage area. I do not think that s. 18 imports that consent shall be given unless the act threatens those qualities or features. However, even if it were to be so read, on the material before the Court, s. 16 must still be viewed as operating to proscribe activities whether or not they pose a threat to the qualities or features of possible outstanding universal value at least until such time as consent is given. That is different both in legal effect and in operation from a law proscribing only activities which threaten the qualities or features which give the area the characteristic that it may be or contain a world heritage area. It may be that evidence could be called to establish that the activities proscribed by one or all of pars. (a), (b) and (c) of s. 16(1) constitute a threat or may reasonably be apprehended to constitute a threat to the features of the protected area which may be of outstanding universal value if undertaken anywhere in the protected area. Section 16(1)(d) is in a different position. It operates by reference to acts capable of adversely affecting the protected area. Even if the qualities and features which give the protected area the quality that it may be a world heritage area were present throughout the entire area — and the evidence is that they are not — proscription by reference to general environmental considerations cannot be viewed as appropriate or adapted to the protection of the features which give to the protected area the quality that it may be a world heritage area. I would, but for the fact that the majority of the Court is of the view that the Act is entirely valid, stand the matter over to enable the presentation of such further evidence as the parties may wish to put before the Court in support of the validity of s. 16(1)(a), (b) and (c). That course being unnecessary, it is sufficient to answer the first question in the case stated as follows: "Section 16(1)(d) and s. 16(2) and (3) (to the extent that they operate by reference to s. 16(1)(d)) are invalid. On the materials before the Court s. 16(1)(a), (b) and (c) and s. 16(2) and (3) (to the extent that they operate by reference to s. 16(1)(a), (b) and (c)) must be held to be invalid." In the view that I have formed it is unnecessary to answer the second question in the case stated. However, it is appropriate that I state that I agree that the second question should be answered in the manner proposed in the judgment of Mason C.J. and Brennan J.