High Court of Australia Wilson, Brennan, Dawson, Toohey and Gaudron JJ. South Australia v Tanner [1989] HCA 3 ORDER Appeal allowed with costs. Set aside the judgment of the Full Court of the Supreme Court of South Australia made on 3 June 1988 and in lieu thereof order that the plaintiffs' summons dated 2 November 1987 be dismissed with costs. Cur. adv. vult. The following written judgments were delivered:— 1989, Feb. 7 Wilson, Dawson, Toohey and Gaudron JJ. The first and second respondents, Mr. and Mrs. Tanner ("the respondents"), are the owners of land in the town of Hahndorf in the Mount Lofty Ranges in South Australia. They wish to develop the land in accordance with the provisions of the Planning Act 1982 SA. The proposed development comprises a number of shops and offices, an aviary and carparks. A development application was approved by the District Council of Mount Barker subject to the concurrence of the South Australian Planning Commission. That concurrence was required because on the respondents' land stands "Thiele Cottage", an "item of the State heritage" within s. 48 of the Planning Act. In due course the Commission resolved not to concur in the granting of approval and consent to the development was therefore refused. The respondents appealed from that decision to the Planning Appeal Tribunal. In the course of the hearing of the appeal a question arose as to the relevance to the issues in the appeal of reg. 37.2 of the Waterworks Regulations 1974 SA made pursuant to the Waterworks Act 1932 SA. As will be seen, the purported effect of reg. 37.2.1 is that it prohibits absolutely the erection of an aviary on the respondents' land. The hearing of the appeal was stood over to allow the respondents to consider their position. The respondents then instituted these proceedings in the Supreme Court of South Australia, seeking a declaration that reg. 37.2 is beyond the power to make regulations contained in s. 10 of the Waterworks Act. Alternatively, they sought a declaration that the Planning Act, in conjunction with the Development Plan made in accordance with its provisions, operates to supersede and impliedly repeal the regulation. The matter was heard by the Full Court of the Supreme Court. By majority (Jacobs and Millhouse JJ., Cox J. expressing no opinion), the Court declared that reg. 37.2.1 is ultra vires the Waterworks Act and invalid. In addition, the Court was unanimously of the opinion that reg. 37.2.1, in its application to the respondents' land, is inconsistent with s. 47 of the Planning Act and therefore can have no effect on the proceedings before the Tribunal. We turn first to the question of validity. The Waterworks Act is the principal legislation governing the supply of water in South Australia. Section 10(1) provides that the Governor may make regulations, inter alia: XXIV. for regulating, controlling or prohibiting the use of any land within a watershed or within a watershed zone so as to reduce or prevent the deterioration or pollution of any water within a watershed or watershed zone. A "watershed" means any area of land for the time being declared by regulation pursuant to s. 9a(1) of the Waterworks Act to constitute a watershed and a "watershed zone" means a "watershed Zone I or a watershed Zone II constituted pursuant to s. 9a(2)" of that Act. In accordance with the power conferred on the Governor by s. 10, the Waterworks Regulations were made and published in 1974. An extensive area of land extending roughly from Williamstown in the north to Myponga in the south was declared by reg. 37.6 to constitute a watershed known as the Mount Lofty Ranges Watershed ("the Watershed") and within this area certain areas were designated watershed Zone I and watershed Zone II. The town of Hahndorf is located within watershed Zone II. Regulation 37.2, which is headed "Control of Piggeries, Zoos and Feedlots in Watersheds", reads as follows: 27.2.1 No person shall erect, construct, enlarge or establish a piggery, zoo or feedlot on any land within a watershed. 27.2.2 The owner or occupier of any land, within a watershed, upon which a piggery, zoo or feedlot was operating at the time this regulation came into force shall be entitled to maintain such piggery, zoo or feedlot provided that such piggery, zoo or feedlot is not relocated elsewhere in a watershed, extended or materially modified except with the approval of the Minister or in accordance with a direction given pursuant to section 58 of the Act, and provided that the provisions of sections 56, 57 and 58 are fully complied with. 27.2.3 For the purpose of this regulation "feedlot" means any building, enclosure, yard or structure on any land upon or within which cattle, sheep or any other stock or animals whatsoever, are held, confined or kept and are usually fed either wholly or partly, by a feeding method other than natural grazing; "piggery" means any building, enclosure, yard or structure on any land upon or within which one or more pigs are kept or run, whether temporarily or permanently; "zoo" means any building, enclosure, yard or structure on any land upon or within which any animals, birds, reptiles or any creatures whatsoever are kept primarily for the purpose of display or exhibition, irrespective of whether any charge is made or payment required for such display or exhibition. 27.2.4 Any person who commits a breach of this regulation shall be guilty of an offence against these regulations. It is common ground between the parties that the aviary proposed by the respondents comes within the definition of "zoo". The starting point of any consideration of the validity of reg. 37.2.1 must be to determine the "true nature and purpose of the [regulation-making] power", to adopt the words of Dixon J. in Williams v. Melbourne Corporation [1] . In order to reduce or prevent the deterioration or pollution of any water within a watershed, the Governor is empowered to regulate, control or prohibit the use of any land within that watershed. There is conferred, therefore, an extensive power governed by a far-reaching purpose. Each of these features is significant. The power is not limited to regulating or controlling the use of land; it extends to outright prohibition of the use of any land within a watershed, provided, of course, that the prohibition has a sufficient nexus to the expressed purpose. Nor is the power conferred simply to reduce the pollution or deterioration of water that has already occurred or is occurring; the object extends to its prevention. The problem of pollution or deterioration of the water may range from slight to grave, and there may be a whole range of measures that might work to reduce or prevent the problem and from which a choice must be made. In many cases it will be impossible to demonstrate that the measures which are adopted will actually be effective. The prudent choice of measures will often depend on administrative practicalities and the availability of expert advice of a scientific nature. In this context, there must be conceded a broad, rather than a narrow, approach in determining the nexus between the exercise of the power and the achievement of the purpose for which it is conferred. 1. (1933) 49 C.L.R. 142, at p. 155. In considering the present challenge to the validity of reg. 37.2.1, it is necessary for the Court to form a view as to the existence and dimensions of the actual or threatened pollution or deterioration of the water in the Watershed. Those are matters of fact upon which the Court must be instructed by appropriate evidence. They are not questions of which the Court may take judicial notice. Once armed with knowledge of the facts, the Court is in a position properly to determine whether the regulation under attack is reasonably capable of being considered a measure "to reduce or prevent the deterioration or pollution of any water within a watershed or watershed zone". In the course of argument, the parties accepted the reasonable proportionality test of validity (cf. Deane J. in The Commonwealth v. Tasmania (the Tasmanian Dam Case) [2] ), namely, whether the regulation is capable of being considered to be reasonably proportionate to the pursuit of the enabling purpose. However, they differed in the answers to which their application of the test led. The same test, in relation to a power limited to regulation, was expressed by Dixon J. in Williams [3] , as being, in substance, whether the regulation goes beyond any restraint which could be reasonably adopted for the prescribed purpose. 1. (1983) 158 C.L.R. 1, at p. 260. 2. (1933) 49 C.L.R., at p. 156. The evidence before the Court shows that the Watershed, to which reg. 37.2 applies, is unique in that it is particularly vulnerable to pollution compared with watersheds in other States. Unlike the situation interstate, the Watershed is largely inhabited and, coming within less than 10 miles of the centre of Adelaide, is extremely accessible. It is also particularly attractive for rural living. Furthermore, because of low rainfall, the Watershed is relatively large in comparison with its effective yield and this accentuates any potential pollutional effect. Increasing urbanization in the Watershed and increasing demand for primary products by the expanding metropolitan area have stimulated animal husbandry and horticultural activities such as pig and poultry raising, dairying, sheep and cattle grazing, market gardening and fruit growing. Mr. Harvey, a senior planning officer with the South Australian Government, has been closely involved with the management of the Watershed over a number of years. By an affidavit filed in the Supreme Court he testified that the controls imposed by the Waterworks Regulations on animal-keeping activities in the Watershed are essential to prevent further deterioration of water quality. He explained that the more intensive animal-keeping activities such as piggeries, zoos and feedlots pose the greater problem because of the difficulty of disposing of the waste generated by them. In the case of zoos, an additional factor which increases the risk they present to the quality of water in the Watershed is their potential to attract people and motor vehicles. More people and vehicles are likely to lead to the construction of more paved areas such as roads, paths and carparks. Paved areas are more likely than open ground to facilitate pollution entering a watercourse because of the run-off of water when it rains. While the impact of additional people and motor vehicles attracted into the Watershed by a single zoo may not cause a large pollution load, the situation has, according to Mr. Harvey, become so critical that any risk of pollution must be addressed. The existence of many small pollution loads generated by different activities taken together is "very significant". In summary, Mr. Harvey concluded: I am of the opinion that the strict controls imposed by the Waterworks Regulations on animal-keeping activities are justified as assisting in the reduction in the deterioration of water quality in the Watershed. The total prohibition on piggeries, zoos and feedlots can be justified on the ground that on the present state of knowledge these activities potentially pose a greater threat to water quality because of the difficulty in the management of waste generated. The Solicitor-General of South Australia, appearing for the appellant, argued that reg. 37.2.1 is valid because it can reasonably be considered that by prohibiting the stated uses of the land it was likely that water deterioration within the Watershed would be reduced or prevented. The choice of means whereby the purpose is to be achieved is for the Governor, so long as there is a sufficient nexus between the means adopted and the end to be achieved. It is not to the point that the threat of pollution which is implicit in the respondents' proposal, viewed in isolation, may be so slight as not to warrant the complete prohibition of the use of the respondents' land for the purpose of an aviary. The aviary might be quite small. The problem of waste management might be handled without difficulty. The attraction of additional visitors to the town of Hahndorf by reason of the existence of the aviary might not increase the existing threat to water quality within the Watershed. Nevertheless, so the argument ran, the sufficiency of the nexus between the exercise of the power and the purpose for which the power is granted is not to be determined by the operation of the regulation in a particular case. The Solicitor-General relied on the decision of the Supreme Court of Victoria in Seeligson v. City of Melbourne [4] , for the proposition that all legislation must of necessity be in "more or less general terms" and a regulation is not to be rendered invalid because its application to particular circumstances is not warranted in terms of the enabling purpose. 1. [1935] V.L.R. 365, at pp. 369-370. On the other hand, counsel for the respondents argued that the failure of the regulation to make any reference to the purpose for which the power is expressly conferred places it beyond power. Since the enabling power is qualified by the terms "so as to reduce or prevent ", it cannot sustain a regulation which contains an outright prohibition of the uses specified. There is no reasonable proportionality between the designated purpose and the total ban on keeping an aviary in a tourist township such as Hahndorf. In considering the submissions made for the respondents, the definition of zoo in reg. 37.2.3 needs to be borne in mind. It is true that, in terms, reg. 37.2.1 contains no reference to the purpose of reducing or preventing pollution of water supplies. However, the concept of "zoo", as defined, identifies a number of factors which collectively demonstrate the potential polluting effect of an aviary: an enclosure or structure; a plurality of birds; kept primarily for the purpose of display or exhibition. These factors raise the prospect of the gathering of members of the public and a potential waste management problem. As we have said, the parties are agreed that the test of validity is whether the regulation is capable of being considered to be reasonably proportionate to the end to be achieved. The line between the opposing arguments is finely drawn. In the end, the answer is largely a matter of impression. On the one hand, in the application of reg. 37.2.1 to the respondents' land, having regard to the proposed development, one could be led to echo the exclamation of Millhouse J.: "Talk about using a sledge-hammer to crack a nut!" On the other hand, a court must exercise care not to impose its own untutored judgment on the legislator, as we think Mitchell J. may have done in Cooper v. Bormann [5] . It is not enough that the court itself thinks the regulation inexpedient or misguided. It must be so lacking in reasonable proportionality as not to be a real exercise of the power. Nor is it enough to point, as did Jacobs J. in his reasons for judgment, to other provisions in the Waterworks Regulations which impose only qualified prohibitions as a step leading to a conclusion that a total prohibition of the kind contained in reg. 37.2.1 is unjustified. To do that is again to substitute the judgment of the court for that of the legislator. 1. (1979) 22 S.A.S.R. 589. In our opinion the regulation is a valid exercise of the power conferred by s. 10(1)XXIV of the Waterworks Act. The evidence of Mr. Harvey shows that the problem of the quality of water in the Watershed is an acute one and that quite extraordinary measures are justified in order to reduce or prevent its deterioration or pollution. For example, it could not be doubted that the establishment within the Watershed of a zoo, as one ordinarily understands that term, could be prohibited absolutely in order to prevent pollution of the water supply. Considered in isolation, an aviary may represent a considerable extension of the ordinary meaning of a zoo, but we are unable to conclude that it was not reasonably open to the legislator to determine that all aviaries established primarily for the display or exhibition of birds and hence with the intention of attracting members of the public should be absolutely prohibited in furtherance of the stated purpose. It remains for us to consider the second branch of the attack on the regulation, namely, whether it is repugnant to, or has been impliedly repealed by, the provisions of the Planning Act. Section 47 of the Planning Act, so far as material, reads as follows: (1) Subject to this Act, no development shall be undertaken without the consent of the relevant planning authority. (5) Where development of a particular kind is expressed, by use of the word "prohibited" in the Development Plan, to be prohibited in a particular area, zone or locality, then, subject to subsection (6), such development is prohibited within that area, zone or locality. (6) Where a development is proposed that would, apart from this subsection, be prohibited under subsection (5), the relevant planning authority may consent to that development if — (a) where the relevant planning authority is a council — the Commission concurs in the granting of the consent; or (b) where the relevant planning authority is the Commission — the Minister and, if the development is to be undertaken in the area of a council, the council concur in the granting of the consent. (7) A consent under this section shall be subject to such conditions (if any) as the relevant planning authority thinks fit to impose (9) In deciding whether to consent to a proposed development under this section, a planning authority — (a) must have regard to the provisions of the Development Plan so far as they are relevant to that decision; and (b) must not make a decision that is seriously at variance with those provisions. The word "development", in relation to land, is defined widely in s. 4(1) of the Planning Act to mean, inter alia: (a) the erection, construction, conversion, alteration of, or addition to, a building on the land; (b) a change in the use of the land; It is common ground between the parties that the activities prohibited by reg. 37.2.1 may constitute "development" within the meaning of the Planning Act. The scheme of the Planning Act centres on the Development Plan ("the Plan"), which may be amended from time to time by a supplementary development plan. The Plan contains a series of objectives, proposals and principles by which all development throughout the State of South Australia is regulated. It will be noted that s. 47(9) requires a planning authority to have regard to the Plan and forbids the authority from making a decision that is seriously at variance with the provisions of the Plan. Incorporated into the Plan is a supplementary development plan for the town of Hahndorf by which certain kinds of development, including "Intensive Animal Keeping", are prohibited. The term "Intensive Animal Keeping" is defined by regulation to include "a feed lot, piggery, poultry battery, dairy, kennel and stable ": reg. 4, Development Control Regulations 1982 SA, made under the Planning Act. The materials before the Court do not establish whether the aviary proposed to be established by the respondents falls within the term. The case has been argued on the broader basis that the activities that are absolutely prohibited by reg. 37.2.1 correspond substantially with activities which fall within the description of "Intensive Animal Keeping" and are therefore prohibited within the meaning of s. 47(5) of the Planning Act. However, notwithstanding that prohibition, the relevant planning authority may, in accordance with s. 47(6), consent to the development. The argument of inconsistency which succeeded before the Full Court was that there is a basic contrariety between reg. 37.2.1 made under the Waterworks Act and s. 47 of the Planning Act. The former imposes a blanket and unqualified prohibition on a development; the latter permits a planning authority, having regard to the Plan, to give consent to the development. The regulation prohibits that which the later Act may permit. Jacobs J., with whose reasons Cox J. generally agreed on this aspect of the case, concluded that: "control of land use ought now to be regarded as exclusively the province of the Planning Act, with the result that a regulation purporting to control land use, and in a different way, must be regarded as impliedly repealed". Millhouse J., with whose reasons Cox J. also agreed, described the Planning Act as providing "a code for undertaking development". The Solicitor-General argued that there is no inconsistency. Both pieces of legislation can stand together and operate cumulatively. They can do this because each Act has a distinct purpose, different from the other. The Waterworks Act deals, inter alia, with the specific problem of the threat of water pollution in a watershed, an identifiable area of special concern. The Planning Act, albeit later in time than the Waterworks Act, establishes a general regime of planning control covering the whole State. Although the supplementary development plan applicable to the respondents' land recognizes the problem of the threat of pollution to water supplies and therefore raises issues similar to those addressed by the Waterworks Regulations, there is no difficulty in requiring compliance with both legislative schemes. Consent under s. 47(6) removes the prohibition imposed by s. 47(5) but the respondents remain bound by reg. 37.2.1. There is nothing surprising about that, given the different purposes of the two statutes and the generality of the Planning Act.. The Solicitor-General also drew attention to other circumstances where the imposition of planning controls under the Planning Act provides only one regulatory device among others operating with respect to the conduct of operations upon particular land. He referred to the Meat Hygiene Act 1980 SA, the Liquor Licensing Act 1985 SA and the Waste Management Act 1987 SA: see also Associated Minerals Consolidated Ltd. v. Wyong Shire Council [6] . 1. [1975] A.C. 538. The circumstances in which a statute will be held to have impliedly repealed an earlier statute are discussed by Fullagar J. in Butler v. Attorney-General (Vict.) [7] : The books contain, of course, plenty of examples of an implied repeal — total or partial — of an earlier statute by a later statute of the same legislature. But it is a comparatively rare phenomenon, and it has been said again and again that such a repeal will not be held to have been effected unless actual contrariety is clearly apparent. I would say that it is a very rare thing for one statute in affirmative terms to be found to be impliedly repealed by another which is also in affirmative terms there is a very strong presumption that the State legislature did not intend to contradict itself, but intended that both Acts should operate. 1. (1961) 106 C.L.R. 268, at pp. 275-276. In our opinion the submission of the Solicitor-General is correct. There is no reason to suppose that the South Australian legislature intended sub silentio to vary the operation of the stringent controls imposed under the authority of the Waterworks Act. The Planning Act is to be read in the light of the maxim generalia specialibus non derogant. It follows, therefore, on the proper construction of the Planning Act, that s. 47(6) does not have the effect that a consent granted pursuant to its provisions overrides the prohibition imposed by reg. 37.2.1. Such a consent removes the obstacle to development derived from s. 47(5) of the Planning Act, but it does not confer a positive authority to proceed regardless of any other law. A similar operation was ascribed to a law in the somewhat analogous situation in Airlines of N.S.W. Pty. Ltd. v. New South Wales [No. 2] [8] . Regulation 198 of the Air Navigation Regulations (Cth) applied so as to prohibit the use of an aircraft in regular intrastate public transport operations except under the authority of, and in accordance with, an airline licence issued by the Director-General of Civil Aviation. It was held that the grant of such a licence was directed only to the safety, regularity and efficiency of air operations. The licence did not confer upon the licensee positive authority to carry on an intrastate air transport business in New South Wales. That subject-matter was governed by the State Transport (Co-ordination) Act 1931 NSW. In order to carry passengers for reward by aircraft from Sydney to Dubbo, the appellant was therefore obliged to comply with the provisions of both the Commonwealth regulations and the State Act. 1. (1965) 113 C.L.R. 54. For the foregoing reasons, we would allow the appeal. The relief sought by the respondents should be refused. Brennan J. The first and second respondents, who are the registered proprietors of a parcel of land in the township of Hahndorf, appealed to the Planning Appeal Tribunal constituted under the Planning Act 1982 SA seeking consent for a development of the land by the erection of offices, shops, an aviary and fifty-three carpark spaces. Towards the end of a lengthy hearing the Tribunal's attention was drawn to reg. 37.2 of the Waterworks Regulations 1974 which provides: 27.2 Control of Piggeries, Zoos and Feedlots in Watersheds 27.2.1 No person shall erect, construct, enlarge or establish a piggery, zoo or feedlot on any land within a watershed. For the purposes of that regulation "zoo" is defined by reg. 37.2.3 to mean: any building, enclosure, yard or structure on any land upon or within which any animals, birds, reptiles or any creatures whatsoever are kept primarily for the purpose of display or exhibition, irrespective of whether any charge is made or payment required for such display or exhibition. If the regulation be valid, the building of an aviary for the public display of birds in Hahndorf is forbidden. Hahndorf is within the Mount Lofty Ranges Watershed constituted by reg. 37.6. That regulation is enacted pursuant to s. 9a of the Waterworks Act 1932 SA. The tribunal adjourned the further hearing of the appeal, and the respondents sought a declaration from the Supreme Court of South Australia that reg. 37.2 of the Waterworks Regulations is invalid, on the grounds (1) that it is ultra vires the regulation-making power contained in s. 10 of the Waterworks Act; or, alternatively, (2) that reg. 37.2 of the Waterworks Regulations 1974 has been superseded by the incorporation of the Mount Lofty Ranges Watershed Supplementary Development Plan into the Development Plan on 27 June 1986 and the operation of the Planning Act 1982 and the Development Plan as from that date. Jacobs and Millhouse JJ. held that reg. 37.2 is beyond the power conferred by s. 10 of the Waterworks Act and is invalid. Cox and Millhouse JJ. held that reg. 37.2 is invalid on the ground that there is a material inconsistency between reg. 37.2 and s. 47 of the Planning Act. If Jacobs J. had not held the regulation invalid on the first ground, he too would have found a material inconsistency. The Court declared reg. 37.2.1 to be invalid and this appeal is brought by special leave to set aside that declaration. Ultra Vires Regulation 37.2 was made in purported exercise of the powers conferred on the Governor by s. 10(1) of the Waterworks Act. When reg. 37.2 was made, pars. XX and XXIV of s. 10(1) conferred power to make regulations: XX. for regulating, controlling or preventing the impairment of the quality of water within a watershed, watershed zone or waterworks: XXIV. for regulating, controlling or prohibiting the use of any land within a watershed or within a watershed zone so as to reduce or prevent the deterioration or pollution of any water within a watershed or watershed zone. In argument, par. XXIV has been advanced as the chief support for reg. 37.2. In deciding whether an impugned regulation is valid, the court has three steps to take: it construes the terms in which the Parliament has conferred the power to make the regulation, it ascertains the scope and legal effect of the impugned regulation and it determines whether the regulation having that scope and legal effect is within the ambit of the power: see Country Roads Board v. Neale Ads Pty. Ltd. [9] ; Swan Hill Corporation v. Bradbury [10] ; McEldowney v. Forde [11] . This approach is similar to the approach adopted by a court in deciding whether a law enacted by the Parliament of the Commonwealth is within the legislative powers conferred by the Constitution (Bank of N.S.W. v. The Commonwealth [12] ; Fairfax v. Federal Commissioner of Taxation [13] ), but an analogy between a decision upon the validity of subordinate legislation and a decision upon the validity of a law of the Parliament is imperfect. A legislative power conferred by the Constitution must be liberally construed unless there is some other constitutional warrant for a narrower construction (Reg. v. Coldham; Ex parte Australian Social Welfare Union [14] ) but in my opinion the same approach cannot be taken in construing a legislative power delegated by a Parliament. Parliament is the organ of government in which legislative power is vested and Parliament should not be held to have delegated to another repository more power than is clearly denoted by the words it has used. In my opinion, a delegation of legislative power should be narrowly construed unless the Parliament has, by express provision or necessary intendment, revealed a contrary intention. 1. (1930) 43 C.L.R. 126, at p. 135. 2. (1937) 56 C.L.R. 746, at p. 756. 3. [1971] A.C. 632, at p. 658. 4. (1948) 76 C.L.R. 1, at pp. 185-187. 5. (1965) 114 C.L.R. 1, at p. 7. 6. (1983) 153 C.L.R. 297, at p. 314. A different approach might be implied from some of the older cases in which it was said that an exercise of a delegated power to legislate is immune from judicial review, either because of the legislative character of the power or (in cases where the power was conferred on a Governor-General or Governor in Council) because of the Crown's supposed immunity from examination of its motive for making the impugned law. That view and the grounds advanced to support it were rejected in Reg. v. Toohey; Ex parte Northern Land Council [15] . That case affirmed the duty of the courts to ensure that statutory powers, whether legislative or not and whether vested in the Executive Government or in another repository, are exercised only in accordance with law. 1. (1981) 151 C.L.R. 170. Paragraph XXIV of s. 10(1) of the Waterworks Act confers a legislative power which is limited by the expression of an object to be served by any regulation made under the power. A valid regulation must be such "as to reduce or prevent the deterioration or pollution of any water within a watershed or watershed zone". There is no power to make a regulation "for regulating, controlling or prohibiting the use of any land within a watershed or within a watershed zone" which is not conducive to that object. Lord Diplock's analysis of the power considered in McEldowney v. Forde [16] is helpful in analysing the power presently under consideration: The relevant characteristic of regulations to which that description refers is the effect to be achieved by them. To be valid their effect must be to promote the preservation of the peace and the maintenance of order. I use the expression "effect" rather than "purpose", for purpose connotes an intention formed by the maker of the regulation to achieve a particular object, and substitutes for the objective test of the effect which the regulation is in fact likely to achieve, the subjective test of what effect the Minister himself whether rightly or mistakenly believes that the regulation is likely to achieve. The distinction which his Lordship draws between effect and purpose is material in this case, but it must be remembered that Lord Diplock is using the term "purpose" in a subjective sense, not as descriptive of an object which a law is apt to achieve. The power conferred by par. XXIV is not contingent on the Governor's opinion as to the likely effect of the regulation to be made, but on its operation. I shall refer to the reduction or prevention of deterioration or pollution of water in a watershed as "the statutory object" to which a valid exercise of the power conferred by par. XXIV must be directed. 1. [1971] A.C., at p. 660. In earlier times, there was a tendency to regard the question whether a regulation is conducive to the fulfilment of a statutory object to be a question of expediency in the exercise of power and, on that account, to be a matter for determination by the repository of the power, beyond the scope of judicial review: see, e.g., Widgee Shire Council v. Bonney [17] ; Williams v. Melbourne Corporation [18] . Perhaps the spectre of unexaminable executive power to which Lord Hewart (The New Despotism (1929)) drew attention (see, e.g., James v. Cowan [19] ) is responsible for the modern tendency to examine more critically the scope and operation of an impugned regulation. The judgment of Dixon J. in Williams v. Melbourne Corporation [20] , is the foundation of the modern approach: To determine whether a by-law is an exercise of a power, it is not always enough to ascertain the subject-matter of the power and consider whether the by-law appears on its face to relate to that subject. The true nature and purpose of the power must be determined, and it must often be necessary to examine the operation of the by-law in the local circumstances to which it is intended to apply. Notwithstanding that ex facie there seemed a sufficient connexion between the subject of the power and that of the by-law, the true character of the by-law may then appear to be such that it could not reasonably have been adopted as a means of attaining the ends of the power. In such a case the by-law will be invalid, not because it is inexpedient or misguided, but because it is not a real exercise of the power: compare Widgee Shire Council v. Bonney [21] . In that case, McTiernan J. [22] treated a submission that the impugned by-law was unreasonable as raising the question "whether, notwithstanding that on its face it relates to traffic, the operation of the by-law is such that it can have no reasonable relation to the purpose for which the power to make by-laws was granted, namely, the order and convenience of the traffic of the city". When the validity of a regulation (I use the term to describe any kind of subordinate legislation purportedly made under a statutory power) is attacked as ultra vires the court will not hold the regulation invalid unless, having regard to its operation in the circumstances to which it applies and to the statutory object to which it must be directed, the regulation could not reasonably have been adopted to achieve the object. The badge of invalidity is not attached merely because the impugned regulation applies in some instances which are immaterial to the fulfilment of the statutory object. In Clements v. Bull [23] the validity of a regulation made by the Melbourne Harbour Trust Commissioners was challenged. The Commissioners had power to make regulations "for or relating to" a number of subjects including the improvement and management of the port and "generally for carrying out the objects and purposes of this Act". The impugned regulation forbade the holding of a meeting or the addressing of an assemblage within the port without the Commissioners' consent. Williams A.C.J. and Kitto J. who, in dissent, would have upheld the validity of the regulation, said [24] : Its operation must have a direct relevance to the management of the port or to some other purpose of the Act; it is not every tendency, however remote, to assist the more efficient conduct of the affairs of the port which will suffice. The point is that the problem is one of characterization by reference to subject-matter. It is not one to be answered by exercising imaginative ingenuity in order to see whether the effect of the provision in some possible or probable instances of its application may be foreign, or even inimical, to the attainment of purposes which fall within the purview of the Act. The first step must be to inquire, what does the regulation really do by way of altering the law in force in the port. The second question is whether a connexion can be seen between that alteration of the law and the control and management of the port . If there is such a connexion the final question arises, whether that connexion is so direct and substantial that the regulation is seen really to satisfy one of the descriptions by reference to which the regulation-making power is conferred. A regulation which is shown by the answers to these questions to be within power cannot be held ultra vires on the ground that in some circumstances it will produce results which are considered unreasonable. If Parliament confers upon a subordinate body a power to legislate for limited purposes, it authorizes even legislation which may be thought unreasonable, provided that nevertheless it is really legislation for those purposes. It may indeed be held invalid on the ground that no reasonable mind could justify it by reference to the purposes of the power: Brunswick Corporation v. Stewart [25] ; but that is only a way of stating the conclusion that no real connexion with the purposes of the power can be seen. Their Honours were in dissent in this case but not, I think, upon any question of principle. Fullagar J. [26] accepted that it would be a "grave mistake" "when the validity of a by-law is in question, to begin by "thinking up" examples of the possible application of the by-law which are at once seen to be capricious, fanciful or absurd, and then to say that the power cannot possibly extend to the creation of such consequences. It was said that such an approach amounted to a reversion to the discredited idea that a by-law could be held invalid because it appeared to a court to be an "unreasonable" provision: see Williams v. Melbourne Corporation [27] ." His Honour held the by-law invalid, however, not because it could have produced unreasonable results in some instances but because it extended to acts and things which could not "reasonably be regarded as the concern of a corporation charged with the management of a port or harbour". It is only in this sense that unreasonableness is relevant to validity. The approaches of Webb J. [28] and Taylor J. [29] accorded with that of Fullagar J. 1. (1907) 4 C.L.R. 977, at pp. 982-983. 2. (1933) 49 C.L.R. 142, at pp. 149-150, 158. 3. (1930) 43 C.L.R. 386, at p. 406. 4. (1933) 49 C.L.R., at p. 155. 5. (1907) 4 C.L.R., at pp. 982, 986. 6. (1933) 49 C.L.R., at p. 159. 7. (1953) 88 C.L.R. 572. 8. (1953) 88 C.L.R., at p. 577. 9. (1941) 65 C.L.R. 88, at pp. 97, 99. 10. (1953) 88 C.L.R., at p. 581. 11. (1933) 49 C.L.R. 142. 12. (1953) 88 C.L.R., at pp. 579-580. 13. (1953) 88 C.L.R., at p. 588. In McEldowney v. Forde [30] Lord Diplock propounded a test of validity which looks to the likely operation of the regulation in the circumstances to which it applies. After referring to the inquiry which the court must make when a power is contingent on a repository's belief that it will achieve a given effect, his Lordship said: But where, as in the present case, the subordinate legislation which the Minister is empowered to make is described in the statute by reference to the effect to be achieved and not by reference to the Minister's own belief in the effect which it will achieve, the relevant inquiry which the court has to make if the subordinate legislation is challenged is not in my view the same. Omnia praesumuntur rite esse acta and the onus lies upon the party challenging the subordinate legislation to establish its invalidity. The Minister's belief in its necessity or expediency is cogent evidence of its validity but it is not conclusive, and the ultimate decision whether or not the likelihood that it will achieve the effect described in the statute is sufficient to bring it within the words of delegation and whether or not it will have any effects which may be prohibited by those words is one for the court itself to make upon the facts proved in evidence before it, or of such general public notoriety that the court may take judicial notice of them without further proof. What degree of likelihood is sufficient and to what extent the likely effect must be confined to that stated in the description are questions for the court itself to determine by construing the words of delegation in the light of the general object that the statute serves, the gravity of the mischief at which the subordinate legislation is aimed and the effect (if any) which it will have upon otherwise lawful acts or property rights of citizens which neither cause nor contribute to that mischief. Lord Diplock's references to the presumption of validity in the exercise of the power, to the "degree of likelihood", the extent to which the operation of the regulation is confined, to the fulfilment of the statutory object, are consistent with the approach taken by Dixon J. in Williams v. Melbourne Corporation. 1. [1971] A.C., at pp. 660-661. In The Commonwealth v. Tasmania (the Tasmanian Dam Case) [31] , Deane J. and I held certain regulations to be invalid. In my view [32] , the generality of the prohibitions imposed by those regulations was such that, in some instances, they would be inimical to the object which they were intended to achieve and in any event they were so wide that they could not properly be characterized as regulations conducive to that object (namely, the protection and conservation of particular properties). Deane J. adopted the test [33] that the regulations would be valid "if they are capable of being reasonably considered to be appropriate and adapted to the protection and the conservation" of the particular property to which they related "in accordance with Australia's obligations under the Convention to protect and conserve the Wilderness National Parks". His Honour then referred to "proportionality", not as a broad, free-standing test of validity but in a very precise context. He referred to "such a lack of proportionality as to render them incapable of being reasonably considered appropriate for the discharge of Australia's obligations under the Convention". That criterion accords with the cases cited. 1. (1983) 158 C.L.R. 1. 2. (1983) 158 C.L.R., at pp. 236-237. 3. (1983) 158 C.L.R., at p. 278. In the light of these authorities, some general propositions may be stated with reference to the validity of a regulation made in exercise of a power which requires that its exercise be conducive to a statutory object. First, as the validity of the regulation depends on whether it answers the statutory description, the problem is one of characterization. Next, the character of a regulation is ascertained by reference to its operation and legal effect in the circumstances to which it applies. The character of the regulation is ascertained by the court's own assessment of the directness and substantiality of the connexion between the likely operation of the regulation and the statutory object to be served. If the directness and substantiality of the connexion between the likely operation of the regulation and the statutory object is so exiguous that the regulation could not reasonably have been adopted as a means of fulfilling the statutory object, the regulation is invalid. Moreover, it must be steadily borne in mind that the fulfilling of the statutory object is a limitation on the power to make the regulation. A regulation which is so widely drawn as needlessly to embrace a field of operation which is quite unconnected with the statutory object cannot reasonably be adopted in exercise of a power so limited. These are broad tests, involving matters of degree. If upon their application the regulation is found to answer the statutory description, it is immaterial that, in some instances, the regulation will not effect or further the fulfilment of the statutory object. Those instances are material only to the court's assessment of the connexion between the regulation and the statutory object. I would add some subsidiary observations. In this country, when the validity of a law depends on some matter of fact, the fact is not ascertained as though it were a mere issue between the parties. In Commonwealth Freighters Pty. Ltd. v. Sneddon [34] , Dixon C.J. said: Highly inconvenient as it may be, it is true of some legislative powers limited by definition, whether according to subject-matter, to purpose or otherwise, that the validity of the exercise of the power must sometimes depend on facts, facts which somehow must be ascertained by the court responsible for deciding the validity of the law. However, validity is a question of law and questions of law do not depend upon a party's discharge of an onus of proof of facts: Breen v. Sneddon [35] ; Gerhardy v. Brown [36] . The court must discover the facts "as best it can": per Dixon C.J. in Commonwealth Freighters [34] . Lord Diplock is right in saying (McEldowney v. Forde [37] ) that there is a presumption of validity but, to the extent that validity depends on some matter of fact, there is no onus on a challenging party which, being undischarged, will necessarily result in a declaration of validity. 1. (1959) 102 C.L.R. 280, at p. 292. 2. (1961) 106 C.L.R. 406, at p. 411. 3. (1985) 159 C.L.R. 70, at p. 142. 4. (1959) 102 C.L.R. 280, at p. 292. 5. [1971] A.C., at p. 661. Where the directness and substantiality of the connexion between an impugned regulation and a statutory object can be properly assessed only with an appreciation of some matter of fact of which the repository of the power has special knowledge or experience, the court should not lightly substitute its own assessment for the assessment made by the repository in enacting the regulation. And, as Lord Diplock observed, the court treats the making of the regulation as "cogent evidence" of the repository's belief in its necessity and expediency. In this case, a different approach was taken in the Full Court. There Jacobs J. said: [A]n examination [of the operation of this regulation in the local circumstances to which it is intended to apply] leads me inexorably to the conclusion that reg. 37.2.1 is so wide in its unqualified prohibition as to go beyond the stated purpose of the power pursuant to which it was made. It must proceed upon the assumption that every piggery, every feedlot, even for a single animal, every zoo, in every part of the vast area of this watershed — on a very rough estimate somewhere between 500 and 1000 square miles — is an unmanag[e]able threat to the watershed, in terms of pollution. It is unnecessary to do more than state that proposition in order to reject for it is in my opinion plainly untenable, and one does not need to conjure up examples to support that conclusion, even if it were permissible to do so. Millhouse J. thought the relationship between the prohibition of an aviary and control of pollution to be "so tenuous as not to justify the regulation". The fact that reg. 37.2 might apply to a piggery, feedlot or zoo which would pose no threat to water quality in the watershed area does not lead to the conclusion that the regulation fails to answer the description contained in par. XXIV. That fact alone does not show that the regulation could not reasonably be adopted to prevent deterioration or pollution of water within the watershed. Measures designed to prevent risks to public health might have to be drawn in wide terms and their application to some situations which prove to be innocuous is not necessarily demonstrative of invalidity: see, e.g., Colville v. Christie [38] . Moreover, before a regulation is struck with invalidity because it is too wide to be reasonably adopted to fulfil a statutory object, the true operation and effect of the regulation must be ascertained. If its terms are reasonably susceptible of a broad construction which would deny it validity or of a narrow construction which would bring it within power, the narrow construction is preferred (ut res magis valeat quam pereat): Widgee Shire Council v. Bonney [39] , per Griffith C.J. That rule applies to reg. 37.2. 1. (1896) 21 V.L.R. 603. 2. (1907) 4 C.L.R., at p. 983. On a literal construction, reg. 37.2 would prohibit some uses of land which would seem to be incapable of affecting water quality in the watershed area. For example, to keep a canary in a cage may, on a literal construction, be held to amount to the establishment of an enclosure upon land within which a bird is kept primarily for the purpose of display. However, the reference to "whether any charge is made" indicates that the regulation is striking at public displays or exhibitions of animals, birds, etc. — not at the keeping of a domestic pet. This is the preferable construction of reg. 37.2. Construing the regulation as a prohibition on such public displays and exhibitions, the object of safeguarding water quality does not appear so remote. Public displays and exhibitions are likely to bring together a number of animals, birds, etc. and to provide adjacent viewing and other facilities for members of the public who are attracted to the display or exhibition. It is obvious that minds will differ on the directness and substantiality of a connexion between a regulation and a statutory object. Although the sufficiency of the connexion is a matter of degree, validity of an impugned regulation is a question of law. Hence, when that question arises on appeal, the appellate court must determine for itself the sufficiency of the connexion. Here, although the threat of water pollution from animal or bird waste or animal-borne or bird-borne diseases must be accepted, there are two features of the regulation which seem to me to deny its validity: (1) the absence of any attempt to prescribe, even in broad terms, any factors (e.g., the number or species of animals or birds) which would be material to the degree of risk to water supply to be apprehended from use of land in the watershed area in one of the forbidden ways; and (2) the uniformity of the prohibition throughout the whole of the watershed area, including the township of Hahndorf, irrespective of the distance of any part of the area from the area of the reservoir and irrespective of the access of the land to any watercourse or other means of transmitting pollution or disease to the water supply. The undiscriminating nature of the regulation certainly reveals that, in many instances, the regulation would apply to an activity which does nothing to enhance the risk of pollution; but it also reveals — and this is relevant to validity — that the regulation has been framed without regard to the limitation contained in par. XXIV. It might have been framed so as to discriminate between those aviaries which pose a risk to water quality (whether by reason of size or number of birds or position or any other material consideration) and those aviaries which do not pose such a risk. Although there is no evidence to describe the risk which aviaries pose to water quality and although there is a presumption in favour of validity, I am unable to conclude that the regulation could not have been framed with more particularity without adversely affecting the fulfilment of the statutory object. Lacking that particularity, reg. 37.2 is too wide and exhibits such a want of proportionality that it could not have been reasonably adopted as a means of fulfilling the statutory object. I would therefore hold that reg. 37.2 is not supported by par. XXIV. Paragraph XX confers no wider power. Regulation 37.2 is invalid. As this is a minority view, I should also state my opinion on the ground of implied repeal. The ground of implied repeal is of some importance for the various licensing regimes in South Australia. The assumption which I make in discussing that ground is, of course, that reg. 37.2 is valid. Implied Repeal by Operation of the Planning Act and Development Plan Section 46(1) of the Planning Act provides: A person must not undertake development contrary to this Division. Section 47(1) provides: Subject to this Act, no development shall be undertaken without the consent of the relevant planning authority. The term "development" in relation to land is defined by s. 4(1) to mean: (a) the erection, construction, conversion, alteration of, or addition to, a building on the land; (b) a change in the use of the land; (c) the construction (except by the Crown, a council or other public authority) of a road, street or thoroughfare on the land (including any excavation or other preliminary or associated works); (d) prescribed mining operations on the land; (e) where the land is an allotment — the division of the allotment (except by strata plan); (f) where the land is an item of the State heritage or is, or forms part of, a State Heritage Area — the demolition, conversion, alteration of, or addition to, the item or the State Heritage Area; or (g) an act or activity in relation to land declared by regulation to constitute development, but does not include an act or activity in relation to land that is excluded by regulation from the ambit of this definition. A planning authority is required to have regard to relevant provisions of a Development Plan in deciding an application for development consent: s. 47(9). A Development Plan includes "principles" which may prohibit a particular kind of development but a planning authority with the consent of the Commission or the Commission with the consent of the Minister may give consent to a development otherwise prohibited: s. 47(5), (6). The Development Plan applicable to Hahndorf (District Council of Mount Barker — Hahndorf Zoning Supplementary Development Plan) prohibits a number of land uses including "Intensive Animal Keeping". That phrase is defined by regulation to include "a feed lot, piggery, poultry battery, dairy, kennel and stable, but does not include a stock slaughter works". The objectives of the applicable plan include two objectives expressed in the Outer Metropolitan Development Plan: Watershed Protection Objective 36: The protection of the Mount Lofty Ranges Watershed against pollution and contamination. Objective 37: The prevention of development which could lead to a deterioration in the quality of surface or underground waters within the Mount Lofty Ranges Watershed. The respondent submits that the Planning Act and the regime established under it now contain the controls over land use in Hahndorf. If so, the prohibition imposed by reg. 37.2 has been impliedly repealed and the only applicable prohibition on land use is the prohibition on development contained in s. 46 of the Planning Act and that prohibition can be lifted by a consent under s. 47. The proposition which was accepted in the Supreme Court was stated by Cox J. in these terms: In my opinion, reg. 37.2.1 of the Waterworks Regulations is inconsistent with s. 47 of the Planning Act in so far as it relates to a proposed change in the use of land or other "development", within the meaning of the definition in s. 4 of the Act, by the erection of a zoo (as the regulation understands that term) on the plaintiffs' land. Jacobs J. found it "impossible to reconcile the blanket and unqualified prohibition on development of the kind referred to in reg. 37.2.1 with the power of a planning authority to consent to the self same development". Millhouse J. concluded that: "[c]ontrol and prohibition cannot exist side by side. One must yield: the regulation, subordinate legislation made earlier, must give way to the later Act." It is implicit, if not express, in the Full Court's finding of inconsistency that the prohibitions in reg. 37.2 of the Waterworks Regulations and in s. 46(1) of the Planning Act are not independent and cumulative. If those prohibitions are independent and cumulative, it is clear that a consent given by a relevant planning authority pursuant to s. 47(1) is effective to lift only the prohibition imposed by s. 46(1). On that hypothesis, there would be no need to reconcile the unqualified prohibition in reg. 37.2 with the power to consent conferred by s. 47(1): the reg. 37.2 prohibition stands whether or not the s. 46(1) prohibition is lifted. In my opinion, the prohibitions contained in reg. 37.2 and s. 46(1) are independent and cumulative. The definition of development in the Planning Act does not embrace every activity prohibited by reg. 37.2.1. For example, a piggery, zoo or feedlot could be enlarged in breach of reg. 37.2 without changing the use of land or converting a building in breach of s. 46(1). And the uses prohibited by the principles of the applicable Supplementary Development Plan do not include a prohibition on the use of land for aviaries, whether containing many birds or few. Although the objectives of planning control include the protection of water quality, the legal controls to effect that object under the Planning Act are simply the prohibition on development and the provision for consent by the relevant planning authority. The Planning Act contemplates that a number of possibly competing objectives may bear upon the desirability of a particular development and that a consent may be granted in some instances even though the preservation of water quality is prejudiced. The legal control for which reg. 37.2 provides is different both in the singularity of its purpose and the absoluteness of its terms. The two statutory regimes have different, though partly coincident, purposes and they may co-exist: see, by way of analogy, Associated Minerals v. Wyong Council [40] . 1. [1975] A.C. 538, at p. 554. If the prohibition on development contained in s. 46(1) were held to repeal any statute which imposed a prohibition on activity which might constitute a "development", some important licensing laws affecting the use of land or premises would be affected. The Solicitor-General offered as instances s. 62(1) of the Liquor Licensing Act 1985 SA, s. 22(1) of the Meat Hygiene Act 1980 SA and s. 17(1)(e) of the Waste Management Act 1987 SA. It is unlikely that the complex of regulatory laws in South Australia was intended to be swept away by the Planning Act and the sundry licensing powers conferred by those laws were intended to be concentrated in the relevant planning authority. In my view, the prohibitions imposed by reg. 37.2 and by s. 46(1) stand independently and cumulatively, and the enactment of the Planning Act left the operation of reg. 37.2 intact. Had I been of the opinion that reg. 37.2 was within power, I would have allowed the appeal. But as the regulation is, in my opinion, invalid, the appeal must be dismissed.