Appeal Panel - Internal CITATION: IPART v Services Sydney Pty Ltd (GD) [2008] NSWADTAP 79 APPELLANTS (1) Independent Pricing and Regulatory Tribunal (2) Premier of New South Wales PARTIES: RESPONDENTS (1) Services Sydney Pty Ltd (2) Sydney Water Corporation FILE NUMBER: 089036 HEARING DATES: 18 July 2008 DATE OF DECISION: 5 December 2008 BEFORE: O'Connor K - DCJ (President); Pearson L - Judicial Member; Blake C - Non-Judicial Member Freedom of Information - Restricted Documents - Reasonable Grounds - Nature of Jurisdiction of Tribunal - section 57 - Relationship with section 63. CATCHWORDS: - Freedom of Information - Business Affairs, Internal Working Documents, Confidential Information Exemptions - Public Interest - Whether Information can be obtained by Use of Powers of Compulsion - Relevance. DECISION UNDER APPEAL: Services Sydney Pty Ltd v Independent Pricing and Regulatory Tribunal and Anor [2008] NSWADT 100 FILE NUMBER UNDER APPEAL: 073180 DATE OF DECISION UNDER APPEAL: 04/03/2008 Administrative Decisions Tribunal Act 1997 LEGISLATION CITED : Freedom of Information Act 1982 (Cth) Freedom of Information Act 1989 Therapeutic Goods Act 1966 (Cth) Attorney General's Department v Cockcroft (1986) 64 ALR 97 Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321 Bag and Jute Co (Tw'th) Pty Ltd and Collector of Customs [1993] AATA 350; (1993) 18 AAR 477 BY -v- Director General, Attorney General's Department [2002] NSWADT 79 Chief Executive Officer, State Rail Authority v Woods (No. 2) (GD) [2003] NSWADTAP 39 Commissioner of the Australian Capital Territory Revenue v Alphaone Pty Ltd (1994) 49 FCR 576 Craig v South Australia (1995) 184 CLR 163 CASES CITED: Dranichnikov v Minister for Immigration and Multicultural Affairs (2003) 197 ALR 389 Harshaw and Australian Competition and Consumer Commission [2007] AATA (26 October 2007) McKinnon v Secretary, Department of Treasury (2006) 228 CLR 423 Minister for Immigration and Multicultural Affairs v Yusuf (2001) 206 CLR 323 Neary v State Rail Authority [1999] NSWADT 107 Re Organon (Australia) Pty Ltd and Department of Community Services and Health: Public Interest Advocacy Centre (1987) 13 ALD 588 Services Sydney Pty Ltd v Independent Pricing and Regulatory Tribunal and anor [2008] NSWADT 100 University of New South Wales v McGuirk [2006] NSWSC 1362 FIRST AND SECOND APPELLANTS M Izzo, counsel/G Shirm, Crown Solicitor's Office REPRESENTATION: FIRST RESPONDENT No appearance SECOND RESPONDENT No appearance 1. Appeal allowed. 2. Orders 2 and 3 of the Tribunal set aside, as they relate to Documents 2, 5, 16, 23, 24 and 27. ORDERS: 3. Order 4 vacated. 4. Leave granted to extend the appeal to the merits. 5. Determination under review affirmed as to Documents 23, 24 and 27. 6. Registrar to arrange a directions hearing attended by the review applicant and the first and second respondents to the review application for the purpose of making directions in relation to the future course of this matter as it relates to the agency's determination in relation to Documents 2, 5 and 16. REASONS FOR DECISION 1 The Independent Pricing and Regulatory Tribunal (IPART) refused Services Sydney Pty Ltd access to some of the documents it sought by an access request made under the Freedom of Information Act 1989 (the FOI Act). Services Sydney applied to the Tribunal for review. 2 The Tribunal delivered a decision on 3 April 2008 with two limbs: one ruling is final, and orders release of some documents, while the other is a ruling as to a contested preliminary issue relating to the operation of s 57 of the FOI Act: see Services Sydney Pty Ltd v Independent Pricing and Regulatory Tribunal and anor [2008] NSWADT 100. 3 IPART now appeals against aspects of both rulings. The documents included documents exclusive to IPART and some which contained material supplied to IPART by a third party, Sydney Water Corporation (Sydney Water). Sydney Water is second respondent to the review application, and second respondent to this appeal. 4 The Tribunal made the following orders: '1. The decision of IPART in regard to Document 3 is affirmed 2. The decision of IPART in regard to Document 2, 5, 16 and 22 is set aside and in substitution thereof a decision that Services Sydney be granted access to these Documents 3. On or before Tuesday 22 April 2008, IPART to provide to the Tribunal, on a confidential basis, a copy of Document 23, 24, 25, 26 and 27 and any other relevant document 4. The application in so far as it relates to Document 23, 24, 25, 26 and 27 is set down for further Directions on Tuesday 6 May 2008 at 10:00am.' 5 Orders 1 and 2 are final, order 3 is interlocutory and order 4 follows on from order 3. Order 1 is not contested. 6 IPART's original notice of appeal put in issue order 2 as it related to documents 2, 5 and 16 and order 3. After the appeal hearing it modified its appeal as it related to order 3, and did not continue to press its case in relation to documents 25 and 26. Its appeal in relation to order 3 is now confined to documents 23, 24 and 27. 7 The Premier has exercised the right given to the Minister administering the Act to be joined to proceedings affected by s 57: see s 57(6). The Premier's interest is in the ruling giving rise to orders 3 and 4. The Premier is the second appellant, and supports the submissions of IPART on the s 57 issue. Order 2 directly affects Sydney Water. Sydney Water took an active part in the proceedings before the Tribunal, but has not taken any active part in the appeal. It relies on the submissions of IPART. 8 The principal respondent, Services Sydney, relies on the decision of the Tribunal, and has not made any additional submissions. 9 Services Sydney and Sydney Water were excused from attendance at the appeal hearing. As a consequence, only the appellants appeared at the appeal hearing, represented by Mr Izzo of counsel. The FOI Requests 10 Services Sydney applied to IPART in March 2007 for access to: 'all information held by IPART related to Sydney Water's 2005 pricing review that among others, include those documents sought in our 2006 FOI application'. 11 The 2006 application sought access to: 'information concerning the building block operating and capital expenditures and cost data used by the Tribunal in its May 2003 Determination on Metropolitan Water Prices for Sydney Water Corporation (including information sighted by the Tribunal's consultants Atkins/Cardino in their assessment of the prudency of Sydney Water's expenditure)'. Background 12 IPART has a number of functions in relation to the regulation of the prices charged to consumers by authorities that have a monopoly to supply infrastructure services such as water and electricity. Sydney Water is a monopoly supplier, responsible for provision of water, wastewater and stormwater services in the Sydney, Illawarra and Blue Mountains areas. Services Sydney is interested in entering into business in the same region for the supply of sewage and water management services. In effect, it is a potential competitor to Sydney Water in part of Sydney Water's monopoly market. 13 Services Sydney has already secured determinations from the relevant authorities permitting it to enter the retail market for sewage collection services, and declaring open to competition, wastewater, transportation and interconnection services provided by the North Head, Bondi and Malabar waste water systems. These matters are outlined in greater detail in the decision under appeal. 14 In its decision the Tribunal explained the process that IPART follows when undertaking a review of proposed prices by a body regulated by the Act, such as Sydney Water. 15 One of the steps involves incorporating data supplied by the regulated body into financial models used by IPART to assist it in determining the price or in approving pricing methodologies. Document 2 and Document 5 are documents generated by IPART but which include data supplied by Sydney Water. They were given the same description in IPART's schedule of documents, i.e. 'IPART Draft Regulatory financial model for metropolitan water agencies'. Document 5 is, according to the Tribunal at [22], an updated version of Document 2. Document 16 was a document supplied to IPART's decision making process. It was described in the schedule of documents as 'Revised and updated page of Sydney Water's draft pricing submission'. 16 On the other hand, Documents 23, 24 and 27 are said by IPART to be connected with the Cabinet process. IPART invoked the Cabinet documents exemption (cl 1) in refusing to release them. It also withheld the documents from the Tribunal, and placed evidence before the Tribunal in support of the submission that IPART had 'reasonable grounds' within the meaning of s 57 of the Act to withhold the documents. 17 The Act, s 3, provides that a restricted document means a document referred to in any one or more of the provisions of Part 1 of Schedule 1. The Cabinet documents exemption appears in Part 1 of Schedule 1. 18 Section 57 provides: ' 57 Consideration of restricted documents (1) The Tribunal may, on the application of the review applicant, consider the grounds on which it is claimed that a document is a restricted document, but only if the document is not subject to a Ministerial certificate. (2) In any proceedings under this section, the Tribunal is, on the application of the Minister administering this Act, or the agency or Minister concerned, to receive evidence and hear argument in the absence of: (a) the public, and (b) the review applicant, and (c) if in the opinion of the Tribunal it is necessary to do so to prevent the disclosure of any exempt matter the review applicant's representative. (3) If the Tribunal is not satisfied, by evidence on affidavit or otherwise, that there are reasonable grounds for the claim, it may require the document to be produced in evidence before it. (4) If, after considering any document produced before it, the Tribunal is still not satisfied that there are reasonable grounds for the claim, the Tribunal is to reject the claim when determining the review application. (5) The Tribunal is not to reject the claim unless it has given the Minister administering this Act a reasonable opportunity to appear and be heard in relation to the matter. (6) For the purposes of any proceedings under this section, the Minister administering this Act is a party to the proceedings.' 19 The documents were described in the schedule of documents as follows: Document 23 : File copy, Appendices A-D to an October 2004 confidential Report to Government by the Institute for Sustainable Futures, University of Technology, Sydney and Centre for International Economics (ISF/CIE) – 'Meeting Sydney's water-demand supply balance'. Document 24: Full copy, Report to the Department of Infrastructure, Planning and Natural Resources by ISF/CIE – 'Meeting Sydney's water-demand supply balance'. Document 27: Letter, dated 25 October 2004, from James Cox, acting IPART Chairman to Director General, the Cabinet Office. 20 The Tribunal held that the evidence established that IPART had 'reasonable grounds' for the claim that Documents 23 and 24 were covered by the Cabinet documents exemption. 21 It was not satisfied that the evidence established 'reasonable grounds' in relation to Document 27. 22 In the instance of documents 23 and 24, it nonetheless held on two bases that it was entitled to call for the documents – one, s 57 did not have the effect of preventing the Tribunal from exercising its usual jurisdiction in FOI review applications requiring it to make the 'correct and preferable' decision in relation to the determination under review (see Administrative Decisions Tribunal Act 1997 (the ADT Act), s 63), and, two, s 57 did not prevent it from exercising the discretion given to an agency under the Act to release documents even though they contain exempt matter (FOI Act, s 25(1)(a)). The Appeal 23 An appeal from a Tribunal decision in relation to an application for review may be made, as of right, in respect of a 'question of law'. By leave of the Appeal Panel it may be extended to the merits: ADT Act, ss 112, 113. It is not necessary for an appellant to establish an error of law as a precondition to the granting of leave to extend to the merits. On the other hand, it would be most unusual to interfere on appeal with a trial decision if there were no error of law of a material kind, and there was no other extenuating factor such as relevant evidence that had not been known or had not been available at the time of the trial. 24 IPART submits that the Tribunal's decision was affected by errors of law, and seeks leave to have the appeal extended to the merits, and for the review application to be finally disposed of by the Appeal Panel without remittal. 25 We will deal first with the objections to the Tribunal's reasoning in respect of Documents 23, 24 and 27. 26 In relation to documents 23 and 24, the submission is that the Tribunal's jurisdiction under the FOI Act is exhausted once it makes a finding of 'reasonable grounds' in relation to a document for which 'restricted document' status is claimed. In this instance a 'reasonable grounds' finding was made. It is submitted that, therefore, the Tribunal should have affirmed IPART's determination instead of making an order requiring IPART to make the documents available to it so that it could determine whether the 'correct and preferable' decision was to refuse or to release the documents. In making the further order, the Tribunal followed the reasoning of the President (the presiding member of this Appeal Panel) in BY -v- Director General, Attorney General's Department [2002] NSWADT 79, leading to the conclusion: 'If the Tribunal finds that there are reasonable grounds for the claim, its jurisdiction remains unaffected and it may go on to ascertain whether the decision to claim the exemption is the correct and preferable decision.' 27 The President said: ' Does s 57 fetter the Tribunal's ordinary jurisdiction (Contention (c))? 68 As I see it, for the reasons given, section 57 operates as a precondition to jurisdiction in relation to the consideration of claims for restricted document status. But the question remains whether s 57 then fetters the ordinary jurisdiction of the Tribunal to ascertain the correct and preferable decision. 69 As noted earlier, Mr Robertson submits that the Tribunal's jurisdiction is ousted because s 57 stands as a 'contrary provision' to the ordinary jurisdiction of the Tribunal to determine what was the correct and preferable decision in the circumstances. 70 It is not clear that s 57 constitutes a 'contrary provision'. One would expect that a provision ousting or limiting the jurisdiction of the Tribunal would be expressed in clear terms, not found by implication. The FOI Act is an Act designed to promote openness in government and enable citizens to understand better the basis for government actions and decisions. It is often described as promoting the democratic objective. The substantial system for review of negative agency determinations reflects the concern that such determinations be sound. There are mechanisms for internal review, review by the Ombudsman and review by the Tribunal. In the case of review by the Ombudsman there is an express limitation on the power of that office to review Ministerial certificate cases. [See s 52(3)] There is no limitation on its power of review in respect of non Ministerial certificate restricted document cases. These are all reasons for expecting that had the Parliament intended to deprive the Tribunal of its ordinary merits review powers in these cases, it would have said so expressly. 71 Mr Robertson relies on the Ministerial certificate cases, Hawker and the Commonwealth cases, to support his position. I agree with their conclusions as they relate to the kind of cases they were dealing with, ones of conclusive certificates. 72 As I see it, the reason that the external review body in the Ministerial (or 'conclusive') certificate case does not proceed any further is that s 59 (in this jurisdiction, and the parallel provisions in the Commonwealth sphere) places an evidentiary bar on it proceeding any further. It is noteworthy in my view that s 59 does not refer to the jurisdiction of the Tribunal. (The first Government version of the 1989 FOI Bill used the term 'evidentiary certificate' before replacing it in the second version with the term 'Ministerial certificate': see Hansard, LA, 3163, 10 November 1988, Mr Moore, Minister for Environment.) 73 Obviously an evidentiary bar of the kind found in s 59 has the same effect as a direct ouster of jurisdiction. In cases where the review body for certificates (the Supreme Court in New South Wales, and the special bench of the Administrative Appeals Tribunal in the Commonwealth) finds reasonable grounds, there is nothing more that can practically be done as the evidentiary bar means that the inquiry is brought to an end. As a result any competing evidence can not be considered and the substantive merits of the claim is thereby determined. 74 In the instance of cases like the present - where a restricted documents exemption is invoked but no conclusive certificate has been issued (presumably because the Administering Minister was not consulted, or, if consulted, did not think it was a situation of such public or political importance that a certificate should issue) - the Parliament could have, but did not, make any provision as to the evidentiary effect of such a claim. 75 Section 59 does not impose any evidentiary bar on the Tribunal in cases where no certificate has been issued. There is no indirect jurisdictional limitation of this kind. Nor is there a direct jurisdictional limitation in that provision or elsewhere in the Act. 76 Accordingly, I consider that s 57 does not operate as a jurisdictional bar in the way suggested by the Administering Minister. In this important respect I agree with the earlier Tribunal decisions, though my reasons are different.' 28 The President refers in the above extract to the 'ordinary jurisdiction' of the Tribunal in FOI matters. 29 The right to make a review application to the Tribunal is conferred by s 53 of the FOI Act. The categories of agency decisions that may be the subject of an application are set out in s 53(3). The ADT Act regulates the jurisdiction of the Tribunal in relation to review of reviewable decisions. 30 The FOI Act does not positively state that the ADT Act's provisions apply to FOI review. However, that is the necessary conclusion from the way the FOI Act deals with the interaction between the FOI Act and the ADT Act at: s 53(4) (internal review provisions of the FOI Act displace ADT Act's provisions); and s 53(5) (provides for the displacement of three only of the provisions of the ADT Act dealing with the Tribunal's review jurisdiction). Sub-section (5) provides: '(5) The provisions of this Division apply to a review application to the exclusion of section 55 (1) (d), section 58 and Division 2 of Part 3 of Chapter 5 of the Administrative Decisions Tribunal Act 1997 .' 31 Accordingly, the Tribunal has proceeded on the basis in dealing with FOI applications that it has the duty set out in s 63 of the ADT Act, i.e.: ' 63 Determination of review by Tribunal (1) In determining an application for a review of a reviewable decision, the Tribunal is to decide what the correct and preferable decision is having regard to the material then before it … (2) For this purpose, the Tribunal may exercise all of the functions that are conferred or imposed by any relevant enactment on the administrator who made the decision.' 32 It will be seen that the reasoning set out above differentiated the position under s 57 from s 59 of the FOI Act. Section 59 allows the Minister to issue a Ministerial Certificate stating that a document is a restricted document. The consequence is that the certificate is to be taken as 'conclusive evidence that the document is a restricted document': s 59(1). There is a procedure to enable such a Ministerial Certificate to be re-examined. The affected party must first bring a review application to the Tribunal, and then the review applicant may make an application to the Supreme Court under s 58A for the Supreme Court to assess whether there are 'reasonable grounds' for the issuance of the certificate. 33 In rejecting this reasoning, IPART relies on dicta in the recent High Court case, McKinnon v Secretary, Department of Treasury (2006) 228 CLR 423. That case arose under the Commonwealth Freedom of Information Act 1982. The Minister issued conclusive certificates under s 36 certifying that disclosure of the internal working documents would be contrary to the public interest. Section 58(5) of the Commonwealth Act provided: '(5) Where application is or has been made to the Tribunal for the review of a decision refusing to grant access to a document in accordance with a request, being a document that is claimed to be an exempt document under section 36 and in respect of which a certificate is in force under that section, the Tribunal shall, in a case where it is satisfied that the document is a document to which paragraph 36(1)(a) applies, if the applicant so requests, determine the question whether there exist reasonable grounds for the claim that the disclosure of the document would be contrary to the public interest.' 34 The Commonwealth Act provides for a special bench of the Administrative Appeals Tribunal to be constituted to deal with an objection to a conclusive certificate. The Tribunal ruled that there were 'reasonable grounds' set out in the conclusive certificate, and held the documents exempt. It saw it as sufficient in this regard that there be credible evidence that showed that there was, as least, one rational ground connected to the public interest for refusing each of the documents. The Administrative Appeals Tribunal did have before it the documents in issue, and there was evidence from agency officers, some received in confidential session. (The Tribunal in fact found several grounds persuasive.) 35 The key question before the High Court was whether the task of the Tribunal was to evaluate in their entirety the reasons (set out in the conclusive certificate) as to why, in respect of each document, disclosure would be contrary to the public interest, i.e. whether there were 'sufficient' grounds not merely one or more rational grounds. 36 Hayne J rejected this wider interpretation of the Tribunal's role. He said, for example, at [55]: 'The Minister's decision that disclosure would be contrary to the public interest is a judgment about which reasonable minds may very well differ. But the Tribunal is not charged with the task of deciding what assessment of the public interest is to be preferred. Its task is to answer the statutory question: are there reasonable grounds for the claim that disclosure would be contrary to the public interest?' 37 At [63] he said: 'In deciding whether reasonable grounds exist for a claim, the Tribunal must take account of any relevant evidence that has been adduced and of any relevant arguments that have been advanced. It must consider the particular claim that has been made and that will require consideration (and commonly the examination) of the particular documents that are in question.' 38 In that case the access applicant had produced to the Tribunal persons with high experience in public administration who expressed the opinion that the various grounds relied upon by the conclusive certificate were not reasonable. Hayne J said at [65]: 'Of course the Tribunal must decide any relevant questions of fact that are tendered for decision in the matter before it. And, if opinion evidence is given, the Tribunal may find it necessary or desirable to decide what, if any, of that evidence it accepts. But it by no means follows that, by tendering evidence of opinion about what is or is not in the public interest, a party may require the Tribunal to decide what view of the public interest is to be preferred. That is not the question that the Act presents for the Tribunal.' 39 Callinan and Heydon JJ agreed. They said at [129] and [131]: '129. … In this area, …, the opinions of witnesses on either side purporting to reveal and express the states of mind and attitudes of others on other occasions will rarely be very helpful and practically never determinative. The role of the Tribunal will usually be best performed simply by examining the documents with a view to assessing whether the stated grounds of conclusiveness satisfy the statutory test. That is because, as here, it will usually be possible readily to characterize the topics in question as topics of public interest without the need for any, or any extensive expert evidence to that effect. The real issue will almost invariably then be whether the document in question, having regard to its date, its author, the position of its author, and its contents, is one in respect of which the Minister can hold the requisite opinion. The Act provides no mandate for any balancing exercise. To have regard to extraneous matters such as other competing reasons, if the requisite statutory reason for non-disclosure has been demonstrated, gives rise to a risk that a de facto balancing act will take place. 131. We are unable to accept the language of the appellant's submission that the effect of the Tribunal's decision is substantially to undermine the Tribunal's proper function of review when a conclusive certificate has been issued. The function of the Tribunal is one which is mandatory and entirely statutory. And while a practical consequence may be that one or more of the stated objects of the Act are thereby defeated, the fact remains that this is a necessary consequence of the express, and as we have already said, unmistakably clear language of the sections with which the Tribunal and the courts are concerned here. The test upon which the Tribunal settled after summarizing a number of earlier cases decided by the Tribunal, and on appeal to the Full Court of the Federal Court, was whether the facts established before the Tribunal were sufficient to support the claim that disclosure would be contrary to the public interest in the mind of a person guided by reason. We would prefer to ask the question in terms of the language of the legislation itself, rather than any adaptation of it, because the former is perfectly clear in asking whether there exist reasonable grounds for the claim that the disclosure of the documents would be contrary to the public interest. The test actually posed by the Tribunal however was certainly, on no view, less advantageous to the appellant than the statutory language prescribes. It does follow, as the majority in the Full Court effectively held, that if one reasonable ground for the claim of contrariety to the public interest exists, even though there may be reasonable grounds the other way, the conclusiveness will be beyond review. It is important to notice that the statutory language does not give an entitlement to access if there are, as often there may very well be, reasonable grounds for the revelation of the document in the public interest. It further follows that the Tribunal is not obliged to undertake a balancing exercise of the kind the appellant submits it was bound to do. The role of the Tribunal in the circumstances of, and on the basis of the statutory language governing this case, is not to undertake a full merits review of the kind contemplated by s 43(1) of the AAT Act. Whether therefore, the only practical and real means of attacking a conclusive certificate will be by demonstrating that there are no reasonable grounds in fact, or that the grounds relied on are so unreasonable that no reasonable person could hold the opinions upon which they are based, does not arise for decision in this appeal.' 40 Section 43(1) of the Commonwealth AAT Act is the provision equivalent to s 63(1) of the ADT Act. 41 In dissent, Gleeson CJ and Kirby J commenced by emphasising the objects of openness and transparency that the Commonwealth FOI Act promotes. Their view was that a more substantive inquiry as to whether the Minister's opinion was held on 'reasonable grounds' was required, favouring the submission of the appellants, one in which account is taken of all relevant considerations including considerations put against those upon which the agency or Minister relied in issuing the certificate. For present purposes, IPART draws attention to the passages in their decision which differentiate the 'reasonable grounds' inquiry (whatever its precise scope) from a full merits review inquiry. Their Honours said at [8]: '8. … [T]he power of review conferred upon the Tribunal by s 58(5) does not involve the exercise of the characteristic function of full merits review described at the commencement of these reasons. It is not the function of the Tribunal to decide whether the Minister was correct to be satisfied that the disclosure of a document would be contrary to the public interest. The Tribunal does not ask itself whether, on the evidence before it, the Tribunal is satisfied that the disclosure of the document would be contrary to the public interest. The question that, by s 58(5), is raised for the Tribunal's decision is a related, but different, question. It is "whether there exist reasonable grounds for the claim that the disclosure of the document would be contrary to the public interest."' 42 While Gleeson CJ and Kirby J differed from the majority on the scope and nature of the 'reasonable grounds' inquiry, all members of the Court were of the view that s 58 established a procedure that did not permit the Tribunal to engage in full merits review. 43 In our view, we should adopt the same position, and the Tribunal should no longer follow the approach preferred in BY on this point. 44 On reflection, we do not consider that a meaningful distinction can be drawn between s 59 (and its review provisions, ss 58A, B and C) and s 57 in this respect. They are parallel provisions involving the same structural approach – the relevant body (the Supreme Court in the s 59 situation, the Tribunal in the s 57 situation) is confined to a reasonable grounds inquiry. Accordingly, the Tribunal was in error in this point. As it found that there were 'reasonable grounds' in respect of Documents 23 and 24, its jurisdiction was exhausted at that point. Its order should have been one affirming IPART's determination in respect of those documents. 45 Finally, we note that in McKinnon the Tribunal had before it the disputed documents. In our view, it would be difficult for the Tribunal to reach a conclusion that a disputed document was properly the subject of a reasonable grounds claim under s 57 without seeing it. This is particularly so where the relevant exemption goes beyond merely requiring that the document fall into a class that can be objectively described, and there is a need to address a discretionary matter (as, for example, in many of the cl 4 instances). The High Court saw it as appropriate and to be expected, as we read its reasons, that the Tribunal had before it the disputed documents. 46 It also follows from these reasons that there is no scope for the exercise of the residual or override discretion identified by the Supreme Court (Nicholas J) in University of New South Wales v McGuirk [2006] NSWSC 1362 at [102] in respect of restricted documents claims. Document 27 47 IPART's submission had been that disclosure of the letter from its Acting Chairman to the Director General of the Cabinet Office would disclose information concerning a deliberation or decision of Cabinet (cl 1(e)). The Tribunal found that there were no 'reasonable grounds' demonstrated. IPART contests that finding. 48 The Tribunal summarised the evidence as follows: '96 In regard to Document 25, 26 and 27, Leigh Sanderson in her statement described the process by which Cabinet make its decisions. This process she said commenced with a Minister placing a proposal, with recommendations, for consideration by Cabinet. Such proposals are made by way of a Cabinet Minute. That Minute is then circulated to other Ministers, and on occasion Government agencies, for consideration and advice. The Cabinet meeting she said was the 'culmination of this process'. 97 Leigh Sanderson went on to say that once a Minute had been submitted for Cabinet consideration, the role of the Department of Premier and Cabinet was to co-ordinate and prepare advice for the Premier for his use as part of the Cabinet process. This she said included obtaining advice from other Ministers and agencies within the Premier's administration who may be affected by the proposal. 98 Leigh Sanderson said that Document 25, 26 and 27 were documents that fell within this process. She said that Document 25 and 26 consisted of a letter from the Director General of the Department of Premier and Cabinet to IPART and attached to that letter was a copy of a Cabinet Minute. Document 27 she said was IPART's response to that letter and the Cabinet Minute. That is, it was her assertion that the Cabinet Minute evidenced deliberations of Cabinet for which the Department of Premier and Cabinet had sought IPART's advice and which was subsequently provided. As mentioned above, no further information, confidential or otherwise, was provided to the Tribunal. 99 In my opinion, in the case of these Documents, IPART has failed to satisfy the tribunal that there are reasonable grounds for the claim that they are exempt under clause 1(1)(e) of Schedule 1 of the FOI Act. Other than mere assertions, no evidence has been provided as to the date of the Cabinet Minute in question, or the subject matter thereof. [Emphasis added.] As IPART has identified the Documents as falling within the ambit of Services Sydney's FOI request it can be assumed that they relate in some way to IPART's 2005 pricing review for Sydney Water. How and what connection they may have, if any, to Document 23 and 24 are not stated.' 49 In its submissions (now confined to Document 27) IPART said that the Tribunal had misdirected itself by asking what the date of the Cabinet Minute was, or the subject matter thereof. The cl 1(e) question, it asserted, was simply whether there were reasonable grounds for concluding, on the evidence, that the letter would disclose information concerning any deliberation or decision of Cabinet. It followed, it was submitted, that the mere fact the letter was a document responding to a Cabinet Minute was enough to establish that there were reasonable grounds for concluding that the letter contained information about a deliberation or decision of Cabinet. IPART also criticised the way Ms Sanderson's evidence was characterised by the Tribunal. 50 We agree with IPART's formulation of the question raised by cl 1(e). In our view, however, it is not unreasonable to seek to put the document for which the claim is made within a framework of reference such as a timetable or an ordered time sequence. This may assist the Tribunal in assessing the veracity of the claim made by the deponent to the affidavit. 51 In our view, the Tribunal was entitled to raise concerns as to the absence of corroborative information of this kind. It was not going so far as to suggest that the legal test under cl 1(e) was one connected with the subject matter of the document as distinct from whether it belonged to a context where an opinion could be formed by the Tribunal that the agency had 'reasonable grounds' for concluding that the letter's release might give rise to the disclosure of, at the least, a Cabinet deliberation. 52 In response to a request from the Appeal Panel to clarify these matters, and directions which followed, IPART has supplied an additional statement from Ms Sanderson going to Document 27 (filed 7 August 2008). Her evidence is that Document 27's contents included advice from IPART responding to the draft Cabinet Minute, and that advice was paraphrased in a Premier's briefing note for use at a meeting of the Ad Hoc Cabinet Committee on Metropolitan Water. The letter of advice is dated 25 October 2004 and the briefing note is dated 26 October 2004. The Committee meeting took place on 28 October 2004. In our view, this evidence (though we have not ourselves called for the letter) is sufficient to dispose of this part of the appeal, without the need to examine closely the error of law submissions made in relation to the Tribunal's treatment of the matter (which were based on the principles enunciated in Craig v South Australia (1995) 184 CLR 163 at 179, and Minister for Immigration and Multicultural Affairs v Yusuf (2001) 206 CLR 323 at [82]); and leave to extend to the merits is granted for that purpose. 53 Accordingly IPART's determination should be affirmed in relation to Document 27. Documents 2, 5 and 16 Background 54 Three exemptions are relied upon in connection with Documents 2 and 5 (business affairs (cl 7(c)), internal working documents (cl 9) and confidential information (cl 13(b)); and two of them in respect of Document 16 (cl 7(c) and cl 13(b)). 55 All of these exemptions have the same basic structure. First of all, the Tribunal must be satisfied that a document falls within the category of documents to which the exemption is addressed. In each instance the Tribunal was satisfied in that respect. 56 Then it is necessary to show that one or two further criteria are met. They require an evaluation of the interest of government that is said to be adversely affected by disclosure. 57 In the case of the cl 7(c) business affairs exemption, the matter to be evaluated is whether disclosure: '(ii) could reasonably be expected to have an unreasonable adverse effect on those affairs or to prejudice the future supply of such information to the Government or to an agency.' 58 In the case of cl 9, the matter to be evaluated is whether disclosure: '(b) would, on balance, be contrary to the public interest.' 59 In the case of cl 13(b), there are two matters to be evaluated, being whether disclosure: '(ii) could reasonably be expected to prejudice the future supply of such information to the Government or to an agency, and (iii) would, on balance, be contrary to the public interest.' 60 It will be seen that there is a similarity of language in the terms of cl 7(c) and cl 13(b)(ii), and there is a similarity of language in the terms of cl 9(b) and cl 13(b)(iii). 61 In the case of documents 2 and 5, the Tribunal said: '(i) cl 7(1)(c) exemption - 32 The essence of their [i.e. IPART's] argument is that, (a) the information was provided voluntarily and in confidence, (b) the disclosure of the information would harm Sydney Water's business in that it would provide information, not otherwise publicly available, about its business and financial affairs to its competitors, and (c) Sydney Water has said it will no longer provide this information voluntarily, thereby prejudicing the future supply of that information to IPART. 33 I accept that the information in Document 2 and 5, so far as it contains information from the AIR provided by Sydney Water, is information provided voluntarily and in confidence. I also accept that some of this information is not otherwise publicly available through annual reports etc. of Sydney Water. However, no attempt has been made to identify for the Tribunal that part of the information that is and is not publicly available. 34 However, in my opinion, Sydney Water, nor IPART, has shown how its business or financial affairs could reasonably be adversely affected by disclosure of the information to competitors: see Watt at [120] to [125]. Even if it were accepted that Sydney Water operated in a competitive market no evidence has been placed before the Tribunal to indicate the nature of an adverse effect, if any, that the disclosure of the AIR information in Document 2 and 5 could have on Sydney Water's business or financial affairs. The information is historical in that it is almost 3 years old and some of it is already publicly available. The fact of competition does not of itself establish the requisite adverse effect. Nor do I accept that at the time these Documents came into existence that Sydney Water was operating in a competitive market. It essentially continued to operate as a State owned monopoly. This does not mean that disclosure of information about its business or financial affairs can never be adversely affected thereby. As I have mentioned, where it is contended that disclosure could give rise to such an adverse effect it is incumbent on the agency making the assertion to place some material before the Tribunal as to what that adverse effect is and that it could reasonably arise from the disclosure of the information in question. The Tribunal can then determine whether that adverse effect is unreasonable in the circumstances. A mere assertion as to the requisite adverse effect will not suffice. … 36 For the reasons set out below, IPART and Sydney Water have also failed to satisfy the Tribunal that the disclosure of Document 2 and 5 could reasonably be expected to prejudice the future supply of information of the kind contained in these Documents. That information I have again assumed to be limited to that which was taken from the relevant AIR of Sydney Water and which is not otherwise publicly available. 37 In Neary v State Rail Authority [1999] NSWADT 107 at [35] the Tribunal held that an objective view must be taken in regard to an agency's claim the document is exempt under this clause. In Attorney General's Department v Cockcroft (1986) 64 ALR 97 (Re Cockcroft), at 107, the Court held that the term 'could reasonably be expected to prejudice the future supply of the information', in the equivalent provision under the Commonwealth legislation, required 'a judgment to be made by the decision-maker as to whether it is reasonable, as distinct from something irrational, absurd or ridiculous, to expect that those who would otherwise supply information of the prescribed kind' to the agency would decline to do so if the 'document in question was disclosed'. In Watt at [132], Judicial Member Montgomery held that information of the 'prescribed kind' or 'such kind' was information of the same kind to that which was contained in the document for which the exemption had been claimed. This appears to be an unnecessarily narrow construction of this exemption, which is not necessary to consider in this application. 38 Sydney Water contended that the decision of the Administrative Appeals Tribunal (Full Tribunal) ('the AAT') in Re Organon (Australia) Pty Ltd and Department of Community Services and Health: Public Interest Advocacy Centre (1987) 13 ALD 588 was applicable to this application. In that application the FOI applicant had sought access to documents lodged by the marketer of an intrauterine contraceptive device, in support of its application to the respondent agency for approval to sell the device in Australia. The documents in question had been provided by the marketer pursuant to the provisions of the Therapeutic Goods Act 1966 (Cth). Under that Act, the responsible Minister, had some compulsive powers to obtain information, however, the documents the subject of the AAT application had been provided voluntarily. The marketer had objected to the disclosure of four documents on the grounds that they contained information of commercial value to its business. The documents in question included a document of statistical information. The AAT was satisfied that the documents in question (including the document with statistical information) had a commercial value and that the disclosure of that information could reasonably be expected to diminish the commercial value of the information. That is, the documents were found to be exempt under the Commonwealth equivalent of clause 7(1)(a) of Schedule 1 of the FOI Act. The AAT having made this finding went on to find that the disclosure of the documents in question could also reasonably be expected to prejudice the future supply of that information to the agency in question. In making its findings the AAT placed weight on the fact that the document containing statistical information went beyond that which was normally required for approval applications under the Therapeutic Goods Act 1966 (Cth) and that the information had been provided voluntarily. 39 The question as to whether the disclosure of the information in Document 2 and 5 could reasonably be expected to prejudice the future supply of information of that kind is ultimately a question of fact having regard to all the relevant circumstances. 40 In my opinion, the circumstances of this application differ substantially to those in Re Organon. For example, in this application no claim has been made that Document 2 and 5 contain information of commercial value to Sydney Water and that this commercial value could be diminished if the information was disclosed. This was a critical finding in Re Organon and on which the subsequent findings of the AAT were based. The legislative schemes also differ substantially. One concerns the granting of approval to the makers and marketers of medical products and devices to sell their products in Australia and the other concerns price regulation of water, gas and electrical services provided to consumers by monopoly State Owned entities. 41 As mentioned above, to perform its role IPART is given specific investigatory powers. On the material before the Tribunal these powers include obtaining information of the nature contained in Document 2 and 5. It is noted from the material before the Tribunal that the AIR template or format was a creation of IPART, who forwarded it to Sydney Water and presumably other service providers for completion. The conclusion to be drawn from this is that the information in the AIR and SIR is indicative of the information IPART requires in order to perform its functions and also that which it would seek compulsorily if required to do so. On this basis it is difficult to see how the disclosure of Document 2 and 5 could reasonably be expected to prejudice the future supply of such information to IPART.' (ii) cl 9 exemption 46 The essence of IPART's argument was that it would be contrary to the public interest to disclose these Documents as they evidence an analytical tool or model used by IPART in the course of its deliberations. I find this argument difficult to understand in light of IPART's statutory functions, which are to be performed in an open and transparent manner. The model has of course now been provided to Sydney Water. Furthermore, disclosure of the model does not mean that IPART has lost its intellectual property rights in the model. 47 In my opinion, while I accept that Document 2 and 5 are based on a 'model' used by IPART in its deliberations of price determinations, I am not persuaded that disclosure of the 'model' would, on balance be contrary to the public interest. However, as the Documents also contain other information, it is necessary to consider whether the disclosure of this information would, on balance be contrary to the public interest. This must be determined as at the date of hearing having regard to all relevant factors, including whether a decision has been made in regard to the deliberations and consultations. 48 In the case of these Documents the deliberations were concluded in September 2005 when IPART made its determination. It is now in the process of making a new determination and it is difficult to imagine that it will be using the same information or model in its deliberations, as there is a new factor, which needs to be taken account of. In my opinion, for these reasons, it cannot be said that on balance the public interest lies in the non-disclosure of the Documents in question. (iii) cl 13(b) exemption 51 I accept that IPART obtained the AIR information contained in Document 2 and 5 in confidence. However, for the same reasons set out in paragraphs [37] and [41] above, in my opinion, IPART has failed to satisfy the Tribunal that the information in question, if disclosed, could reasonably be expected to prejudice the future supply of such information it.' 62 In the case of document 16, the Tribunal said: '(i) cl 7(1)(c) exemption 60 Once again Sydney Water and IPART have placed no material before the Tribunal, which shows what the adverse effect, if any, on the business or financial affairs of Sydney Water, if the information was disclosed, other than to say that it would provide potential competitors with information that had been provided in confidence. Accordingly, for the same reasons set out in paragraph [34] and [35] above, IPART and Sydney Water have failed to satisfy the Tribunal that the disclosure of the information in Document 16 could reasonably be expected to have an unreasonable adverse effect on those affairs. 61 For the same reasons set out in paragraph [37] and [41] above, IPART and Sydney Water have failed to satisfy the Tribunal that the disclosure of the information in Document 16 could reasonably be expected to prejudice the future supply of such information to IPART. 62 While it is accepted that the material was provided in confidence, this on its own is not sufficient for the exemption to apply. Nor is there any evidence before the Tribunal to indicate whether the information contained in Document 16 formed part of the final submission lodged with IPART and whether that submission was publicly available. (ii) cl 13(b) exemption 63 For the same reasons set out in paragraphs [50] and [51] above, IPART and Sydney Water have failed to satisfy the Tribunal that the information contained in Document 16 is exempt under clause 13(b) of Schedule 1 of the FOI Act.' Voluntary Obtaining of Information versus Use of Powers of Compulsion 63 As this case illustrates, whereas once IPART (and its predecessor, the Government Pricing Tribunal) operated in an environment where the utilities whose prices it regulated held a monopoly, modern competition policy is now seeking to encourage new entrants into markets for water services, electricity services and the like. Inevitably, therefore there will be interest on the part of new entrants as to the way in which prices are set, and how decisions of IPART are reached. 64 IPART referred in particular to para [41] of the reasons for decision. In dealing with the cl 7(1)(c) and cl 13(b) claims invoked by IPART in relation to documents 2, 5 and 16, the Tribunal saw as a significant factor negative to the case of IPART that IPART could obtain the kind of information provided by the regulated party by the use of powers of compulsion if the requested party declined to give the information voluntarily. 65 The Tribunal had given the following summary of the evidence of IPART's practices, which was not challenged at the appeal: '2 IPART's usual practice in conducting a metropolitan water pricing review is to first publish an Issues Paper that is made available for public viewing: see Statement of Colin Reid at [15]. It then seeks submissions from relevant stakeholders. These are usually provided voluntarily in two forms, a public form and a confidential form. The confidential form containing information the stakeholder in question regarded as being commercially sensitive. IPART has compulsive powers to obtain information (see section 22 of the IPART Act). However, this power has not been used to date for a pricing investigation in regard obtaining information from a regulated agency such as Sydney Water: see Statement of Colin Reid at [23]. 13 IPART conducts public hearings as well as seminars and workshops so as to enable the regulated agencies to present their case and stakeholders to comment thereon (see section 21 of the IPART Act). Hearings can be conducted in private where IPART is of the view that it is desirable to do so (see sub-section 21(5) of the IPART Act). IPART has an obligation to make available for inspection, to any person who so requests, a document obtained by IPART in connection with the investigation (including submissions and documents obtained pursuant to its compulsive power) unless the document is exempt under the FOI Act: see sub-section 22A(1) of the IPART Act. Even where a document is exempt under the FOI Act, IPART has a discretion to make the document available for inspection to a person who has an interest in the investigation, subject to IPART giving the person who provided the document an opportunity to make submissions on whether the document should or should not be made available and it is satisfied that making the document available for inspection could not reasonably be expected to damage the commercial or other interests of that person or the State: see sub-section 22A(2) of the FOI Act. 14 The investigatory process can take up to 15 months before a final determination is published. In regard to the 2005 price determination, a final determination was made and published by IPART on 2 September 2005. 15 Between pricing determinations, Sydney Water and the other regulated agencies voluntarily submit to IPART an 'Annual Information Report' ('AIR'), which is a detailed account of commercial information. This information enables IPART to assess the consistency of its assumptions in reaching its pricing determination. And in those years in which a pricing investigation is underway, these agencies will provide a 'Special Information Report' ('SIR'), which contains more specific data to that contained in the AIR. Each report contains more information than what is contained in the annual reports of the relevant agencies: see Statement of Diane Nolder dated 28 September 2007 at [61].' 66 Section 22 to which the Tribunal referred provides: ' 22 Tendering information, documents and evidence (1) For the purposes of an investigation, the Chairperson may, by notice in writing served on an officer of a government agency or on any other person, require the officer or other person to do any one or more of the following: (a) to send to the Tribunal, on or before a day specified in the notice, a statement setting out such information as is so specified, (b) to send to the Tribunal, on or before a day specified in the notice, such documents as are so specified, (c) to attend at a hearing before the Tribunal to give evidence. (2) If documents are given to the Tribunal under this section, the Tribunal: (a) may take possession of, and make copies of or take extracts from, the documents, and (b) may keep possession of the documents for such period as is necessary for the purposes of the investigation to which they relate, and (c) during that period must permit them to be inspected at all reasonable times by persons who would be entitled to inspect them if they were not in the possession of the Tribunal. (3) A person (not being an officer of a government agency) who attends at a hearing because of a notice under this section is entitled to be paid by the State such allowances and expenses as are prescribed by the regulations or (subject to the regulations) as are approved by the Treasurer. (4) (Repealed)' 67 IPART challenged the Tribunal's rejection of its case as to the value of acquiring information from regulated parties by voluntary means simply on the basis that it had powers of compulsion. 68 It submitted that the Tribunal should have dealt properly, and did not, with its evidence as to the importance to IPART and the effectiveness of its processes of having regulated bodies provide information voluntarily with assurances of strict confidentiality rather than being forced to use its statutory powers to compel the provision of information. 69 The Tribunal had not, it contended, addressed the detailed case that IPART had made on this point. At the very least there was a failure to accord procedural fairness, and, it was submitted, a failure of such a degree that there had been a 'constructive failure to exercise jurisdiction' – relying on the High Court decision in Dranichnikov v Minister for Immigration and Multicultural Affairs (2003) 197 ALR 389. 70 We observe that Dranichnikov belongs to the 'constitutional writs' case law of the High Court. Dranichnikov was a case where the anterior question was what was the particular social group into which an applicant for a protection visa fell for the purpose of assessing his claim that he had a reasonable fear of persecution if he were forced to return to his home country. In the opinion of a majority of the Court the responsible tribunal failed properly to characterise the particular social group, and had defined it too broadly. It was clear, it considered, that the applicant's case placed him in a particular social group of a narrower class. This failure properly to characterise the applicant's case meant that the true case had not been heard, with the result that there was a 'constructive failure of jurisdiction', which in turn justified the issuance of prerogative relief under s 75(v) of the Constitution. 71 In this case, the Tribunal, sufficiently in our view, described the case put by IPART. We are not inclined to the view that the Tribunal so misunderstood the case as to have deprived itself of jurisdiction. However, there are, we consider, difficulties with the Tribunal's analysis. 72 In our view, the existence of powers of compulsion is no more than a consideration to be taken into account in assessing the future effect on an agency's operations of it disclosing commercial information supplied in confidence to a commercial rival. It is, we think, a familiar aspect of the operation of regulatory bodies that they seek to obtain relevant information by non-coercive means. In our view, a practical distinction can be drawn between 'voluntary' obtaining of information and 'compulsory' obtaining of information. It is, we think, tenable to suggest, as IPART did here, that the work of a regulatory agency is made easier by not having to invoke powers of compulsion, and that it is desirable to have a co-operative relationship with regulated parties. The existence of the coercive power is a fail-safe. 73 Coercive power is rarely, we think, seen by Parliaments as the primary means by which regulatory bodies should acquire relevant information. There may, we think, be a qualitative difference operationally between the extent of information that is acquired through co-operative means and that acquired by use of powers of compulsion. 74 A similar point has come up in cases where agencies have resisted FOI requests by the subject of a complaint for the details of a complaint made by a third person. Agencies have argued that their ability to receive complaints would be impaired if complainants thought that their complaint would be revealed under FOI as a matter of routine. Agencies have accepted that a point may be reached in the process where natural justice necessitates disclosure of the substance of the complaint and the identity of the complainant (for example, the laying of disciplinary charges, or laying of criminal charges). The Appeal Panel has accepted that a proper distinction along those lines can be drawn depending on the point the complaint investigation process has reached. See for example, Chief Executive Officer, State Rail Authority v Woods (No. 2) (GD) [2003] NSWADTAP 39 at [77] to [87]. 75 In Re Cockcroft the regulatory body had no power to compel the provision of information. It dealt with a sensitive subject (discrimination in employment), and the Administrative Appeals Tribunal and, on appeal, the Federal Court recognised the importance of a co-operative approach to the effective performance of the body's work. See also Bag and Jute Co (Tw'th) Pty Ltd and Collector of Customs [1993] AATA 350; (1993) 18 AAR 477. 76 The Tribunal's assumption in this case appears to have been that there would be no practical difference between the information presently being obtained voluntarily, and that which could be obtained by use of powers of compulsion. If that is the case, then the adverse effect claimed by IPART may well be illusory. However, as we interpret IPART's position, it is saying that were it forced to rely on powers of compulsion it would not get in future the depth and breadth of information it presently receives, and perhaps in a less timely way. If there is a difference in the quality and depth of information provided, this may be material. This issue was not explored in the reasons. 77 Similar submissions were recently considered by the Commonwealth Administrative Appeals Tribunal: see Harshaw and Australian Competition and Consumer Commission [2007] AATA (26 October 2007) (Senior Member Penglis). The agency refused to disclose, on the ground of prejudice to future supply of similar information, a document containing commercially confidential information that had been provided voluntarily by a regulated body. Its submissions referred to the value of obtaining information voluntarily, and the difficulties that would be experienced if it could only obtain that information by the exercise of powers of compulsion. The Tribunal accepted the submission. 78 We note that there are also statutory obligations of confidentiality applying to the way IPART conducts itself in relation to information acquired during the monitoring period, in contrast to the requirements of public disclosure that ordinarily apply to any documents received during the formal price determination inquiry period (as to which see s 22A). In the Part headed Price Determinations – Monitoring, s 24 AD provides: ' 24AD Confidential information (1) If a person provides information to the Tribunal in connection with functions under this Part on the understanding that the information is confidential and will not be divulged, the Tribunal is required to ensure that the information is not divulged by it to any person, except: (a) with the consent of the person who provided the information, or (b) to the extent that the Tribunal is satisfied that the information is not confidential in nature, or (c) to a member or officer of the Tribunal. (2) If the Tribunal is satisfied that it is desirable to do so because of the confidential nature of any information provided to the Tribunal in connection with functions under this Part, it may give directions prohibiting or restricting the divulging of the information. (3) A person must not contravene a direction given under subsection (2). Maximum penalty: 100 penalty units or imprisonment for 6 months, or both. (4) A reference in this section to information includes information contained in any evidence given at a meeting of the Tribunal and information contained in any documents given to the Tribunal.' 79 This is a statutory indication that tends, we think, to support IPART's claim of contrariety to the public interest (cl 9, cl 13(b)) or prejudice to a relevant degree (cl 7(c), cl 13(b)). 80 Both of the factors mentioned should have been addressed. Our conclusion is two considerations relevant to the exercise by the Tribunal's discretion were not considered. Future Use of Modelling Information 81 IPART criticised a statement made by the Tribunal at para [48] in dealing with the evaluative aspect of cl 9, the internal working documents exemption, as it applied to the models that were the subject of Documents 2 and 5, and included data supplied by Sydney Water via the AIR/SIR process. The Tribunal said that: 'It is now in the process of making a new determination and it is difficult to imagine that it will be using the same information or model in its deliberations, as there is a new factor, which needs to be taken into account.' The new event to which the Tribunal was referring was the new pricing review requested by the Premier in June 2007 (the same month as the review application was lodged in the Tribunal) to consider the impact on prices of the decision to build the desalination plant at Kurnell. 82 IPART objects that the Tribunal did not signal to it in the course of the hearing that it might give weight in its evaluation to this development. Moreover, IPART pointed to evidence (in Mr Reid's statement, para 48) said to be to the contrary – 'the modelling comprises intellectual property belonging to IPART which is of ongoing use in the conduct of pricing determinations it undertakes including the current review of SWC prices'. 83 We agree with IPART's submissions on this point that the Tribunal erred in law in that it raised an inference where there was no evidence to support it (see Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321 at 355-356) and that the inference was not an obvious one arising from the material before the Tribunal, resulting in a denial of procedural fairness (Commissioner of the Australian Capital Territory Revenue v Alphaone Pty Ltd (1994) 49 FCR 576 at 591-592). Conclusion 84 In our view the orders of the Tribunal challenged by the appeal should be set aside. A final order should be entered in relation to Document 27. 85 Leave to extend to the merits should also be given in relation to the Tribunal's decision as it pertains to Documents 2, 5 and 16. We see no utility in referring the re-examination of IPART's exemption claims back to the Tribunal. In this regard we note that the Tribunal did not rely entirely on the points criticised in the appeal by IPART. The Tribunal was also critical of the lack of particulars as to other matters in the IPART case, especially a lack of evidence as to the nature of the adverse effect. 86 Services Sydney did not appear, with the leave of the Appeal Panel, at the appeal hearing. We think Services Sydney should be given an opportunity to indicate now whether it wishes to proceed with its review application as it relates to Documents 2, 5 and 16. Sydney Water also has a direct interest in these documents, and may wish to be heard. Accordingly a directions hearing will be held to decide the future course of the matter. Orders 1. Appeal allowed. 2. Orders 2 and 3 of the Tribunal set aside, as they relate to Documents 2, 5, 16, 23, 24 and 27. 3. Order 4 vacated. 4. Leave granted to extend the appeal to the merits. 5. Determination under review affirmed as to Documents 23, 24 and 27. 6. Registrar to arrange a directions hearing attended by the review applicant and the first and second respondents to the review application for the purpose of making directions in relation to the future course of this matter as it relates to the agency's determination in relation to Documents 2, 5 and 16. DISCLAIMER - Every effort has been made to comply with suppression orders or statutory provisions prohibiting publication that may apply to this judgment or decision. The onus remains on any person using material in the judgment or decision to ensure that the intended use of that material does not breach any such order or provision. Further enquiries may be directed to the Registry of the Court or Tribunal in which it was generated.