Commissioner of Police, New South Wales v Guo

The legislation 29 In our opinion, the application raises a question of statutory construction of the provisions of the Administrative Appeals Tribunal Act, in particular of s 36D(6) of that Act which we set out at [34] below. The question is not of easy resolution. 30 Section 33 provides that the procedure of the Tribunal is within the discretion of the Tribunal; the proceeding shall be conducted with as little formality and technicality, and with as much expedition, as possible; and the Tribunal is not bound by the rules of evidence but may inform itself on any matter in such manner as it thinks appropriate. 31 Section 35 provides that the hearing of a proceeding before the Tribunal shall be in public, subject to s 35. The Tribunal, where satisfied that it is desirable to do so, may direct that a hearing or part of a hearing shall take place in private and give directions as to the persons who may be present; directions prohibiting or restricting the publication of the names and addresses of witnesses; directions prohibiting or restricting the publication of evidence or of matters contained in documents lodged with the Tribunal; and give directions prohibiting or restricting the disclosure to some or all of the parties to a proceeding of evidence given by the Tribunal or of the contents of a document so lodged. 32 Sections 36 and 36A are concerned with what happens if the Attorney-General of the Commonwealth certifies by writing that the disclosure of information concerning a specified matter or the disclosure of any matter contained in a document, would be contrary to the public interest for a reason that could form the basis for a claim by the Crown in right of the Commonwealth in a judicial proceeding that the information or the matter contained in the document should not be disclosed. 33 Sections 36B and 36C are equivalent provisions where the Attorney-General of a State (which is defined by s 3(1) to include the Northern Territory and the Australian Capital Territory) so certifies. 34 Section 36D is of central importance and relevantly provides as follows: 36D Public interest questions under sections 36, 36A and 36C … Parties to be notified of Tribunal's decision (1) As soon as practicable after making a decision: (a) under subsection 36(3) or 36B(3) in relation to information, or matter contained in a document, in relation to a proceeding; or (b) under paragraph 36A(2)(b) or 36C(2)(b) in relation to the answering of a question at the hearing of a proceeding; the Tribunal shall give to each party to the proceeding a document setting out the terms of the Tribunal's decision. Question of law (2) For the purposes of this Act: (a) the question whether information, or matter contained in a document, should be disclosed to the parties to a proceeding; or (b) the question whether the answering of a question would be contrary to the public interest; is a question of law. Constitution of Tribunal (3) The Tribunal's power to make a decision under subsection 36(3) or 36B(3) or paragraph 36A(2)(b) or 36C(2)(b) may be exercised only by the Tribunal constituted by a member who is a Judge of the Federal Court of Australia. Appeals (4) A decision by the Tribunal: (a) under subsection 36(3) or 36B(3) as to whether or not information, or matter contained in a document, should be disclosed to all or any of the parties to a proceeding; or (b) under paragraph 36A(2)(b) or 36C(2)(b) that the answering of a question at the hearing of a proceeding would, or would not, be contrary to the public interest; is a decision by the Tribunal in that proceeding for the purposes of section 44. Disclosure of information etc. to officers and staff of Tribunal (5) Nothing in section 36 or 36B prevents the disclosure of information, or of matter contained in a document, to a member of the staff of the Tribunal or to an officer of the Tribunal in the course of the performance of his or her duties as a member of the staff of the Tribunal or an officer of the Tribunal. Public interest (6) Sections 36 and 36B exclude the operation of any rules of law that relate to the public interest and would otherwise apply in relation to the disclosure of information, or of matter contained in documents, in proceedings before the Tribunal. Commonwealth Attorney-General or State Attorney-General may appear or be represented (7) The Attorney-General, or the Attorney-General of a State: (a) may appear before the Tribunal personally, or may be represented before the Tribunal by a barrister, solicitor or other person, in order to inform the Tribunal of his or her opinion in accordance with section 36A or 36C; or (b) may so inform the Tribunal of his or her opinion by causing to be sent to the Tribunal a written certificate that is signed by him or her and sets out that opinion.

The reasons of the Tribunal 35 The reasons of the Tribunal may be summarised as follows. 36 The Tribunal first considered earlier decisions of the Tribunal in relation to public interest immunity. 37 In Re Hobart Central Child Care Pty Ltd and Commissioner of Taxation [2004] AATA 1222; 84 ALD 86 the Tribunal (Deputy President Forgie) concluded at [76] that s 36D(6) of the AAT Act was not intended to exclude the general operation of considerations of public interest immunity in proceedings in the Tribunal. It was intended instead to exclude its operation only when an Attorney-General has given a certificate under ss 36 or 36B and those provisions came into play. Otherwise, if disclosure of a document is resisted on the basis of its being subject to public interest immunity, the Tribunal was bound to consider the claim and make a decision on whether or not it applied. 38 The Tribunal doubted the strength of the key building blocks of the reasoning in Hobart Central Child Care. 39 The Tribunal also referred to the reasoning of Gray J, the Presiding Member of the Tribunal in Re Queensland Nickel and Great Barrier Reef Marine Park Authority [1991] AATA 277;25 ALD 160; that of Deputy President McMahon in Re Ajka Pty Ltd and Australian Fisheries Management Authority (1995) 39 ALD 445; and that of Deputy President Forgie in Re Kanina Banner and Minister for Health and Ageing [2002] AATA 169; 66 ALD 663. 40 The Tribunal concluded, at [37], that by limiting the focus in Hobart Central Child Care to a narrow discussion about whether s 36D(6) should be read as applying only to the circumstances in which an Attorney-General of the Commonwealth or a State makes a claim of privilege, DP Forgie, in that respect, addressed an argument not made by DP McMahon. Her reasoning in Hobart Central Child Care therefore failed to consider both the substantive argument DP McMahon had advanced in Ajka and her own similar reasoning expressed two years earlier in Kanina Banner. 41 Another reason the Tribunal gave to doubt the reasoning in Hobart Central Child Care was that no consideration was given to s 130 of the Evidence Act 1995 (Cth). The Tribunal said that because it was not bound by any rules of evidence (s 33 of the Administrative Appeals Tribunal Act), the decision in Hobart Central Child Care can only be sustained if public interest immunity can be characterised as a substantive rule of law rather than a rule of evidence. The Tribunal reasoned that the Commonwealth Parliament has therefore enacted laws, substituting for the common law, statutory rules in the Evidence Act to govern the reception or exclusion of evidence of matters of state in Commonwealth judicial proceedings. This might be reason to conclude that the correct characterisation of such rules in any federal proceeding, whatever might have been earlier contended, had been resolved by the Parliament in favour of their properly being characterised as rules of evidence. In any event, there is no mention of the Evidence Act or any discussion of that consideration in Hobart Central Child Care. 42 A third reason to be sceptical of Hobart Central Child Care, the present Tribunal said, was the lack of consideration of Re Pochi and Minister for Immigration and Ethnic Affairs [1979] AATA 64; 36 FLR 482 (Re Pochi). The present Tribunal concluded that Brennan J's approach in Re Pochi was logically inconsistent with the existence of a right to claim common law public interest immunity in the Tribunal. That was because at common law such immunity was not, and never has been, a private testimonial privilege. The duty to recognise the immunity was independent of a claim for the privilege being made by a party. If there was a recognised public interest to be protected, a court must identify and protect that interest even if the parties or the Crown do not make an application. The present Tribunal said that Brennan J expressly stated in Re Pochi that, in the deportation case before him, the public interest in protecting the sources of information used to combat crime was "paramount". Given this statement, the common law public interest doctrine, had it applied in the Tribunal, would have obliged the President to rule that the evidence not be adduced and to refuse any cross-examination upon it. The common law privilege, had it applied, would not have been capable of being waived. Brennan J would have been in error, if the common law of public interest immunity applies in the Tribunal, in not drawing attention to that immunity and excluding that evidence. The decision in Hobart Central Child Care did not address Brennan J's central reasoning. It did not grapple with his conclusion that the Tribunal can have regard to evidence that could not be adduced in a court because in a court that would be precluded by the common law doctrine of public interest immunity. 43 The present Tribunal decided not to follow Hobart Central Child Care. It was not satisfied that the decision in Hobart Central Child Care expressed a settled view of the law that could be regarded as having been consistently applied in the Tribunal. Indeed, rather than the decision in Hobart Central Child Care representing a settled position the present Tribunal came to the view that the weight of authority and practice in the Tribunal, if a claim for the protection of the public interest is made and there has been no intervention by an Attorney-General, remains that as established in Re Pochi. 44 The Tribunal then turned to consider the legislative history. It stated that viewing ss 36, 36A, 36B and 36C as express provisions that "preserved" public interest immunity but limited it to those legal mechanisms was consistent with the historical record. 45 The Tribunal said, at [68], that when the Administrative Appeals Tribunal Act was originally enacted, only the Commonwealth Attorney-General was given the power to certify that the disclosure of certain information would be contrary to the public interest. Section 36(1) of the Administrative Appeals Tribunal Act provided the Commonwealth Attorney-General could certify that the disclosure of information concerning a specified matter or the disclosure of the contents of a document would be contrary to the public interest. 46 Section 36(5) of the Administrative Appeals Tribunal Act at that time provided that s 36 excluded the operation of any rules of law that relate to public interest that would otherwise apply in relation to the disclosure of information or of matter contained in documents in proceedings before the Tribunal. 47 Clause 94 of what the Tribunal accepted was the Explanatory Memorandum to the Administrative Appeals Tribunal Bill 1975, but which further research suggests may have been a draft of such a document, explained the purpose of s 36(5) as follows: What used to be known as Crown Privilege, namely the right of the Government to avoid disclosure of documents on the ground of public policy, has been dealt with by the sub-clauses (1)-(4) of this section. Sub-clause (5) leaves the existing law unaltered as it relates to such matters as solicitor-client privilege or answers to incriminating questions … 48 Clause 94 of that document then referred to an extract from the report of the Bland Committee, identified in the introduction to the Explanatory Memorandum as the Committee on Administrative Discretions: The decision maker should be required to make available to the Tribunal all relevant documents in his possession. Yet there must be proper protection of confidentiality of material on security or other sensitive grounds. While the public interest normally demands open hearings (as provided for in clause 35), there can be no disputing that a Tribunal will frequently find itself faced with material whose confidentiality must be preserved if, indeed, it is to be available to enable the right decision to be reached. It seems to us that the appropriate Minister must have power to specify which documents (if any) must, on the grounds mentioned above, be regarded as confidential to the Tribunal or the conditions under which the information they contain may be made available to the applicant or his representative or more widely. 49 Two years later the Administrative Appeals Tribunal Act was amended by the inclusion of s 36A (Appeals Tribunal Amendment Act 1977 (Cth)). There is no Explanatory Memorandum for the Bill for that Act but the Attorney-General's (Mr Ellicott QC) Second Reading Speech outlined the reasons for the new provision (as is relevant) as follows: The Act does not provide for the Attorney-General to claim a like immunity from disclosure in respect of an answer to a question asked of a witness in proceedings before the Tribunal. New section 36A to be inserted by clause 23 of the Bill, makes provision for this to be done. 50 Sections 36B and 36C were only later included in the Administrative Appeals Tribunal Act by the Law and Justice Legislation Amendment Act 1988 (Cth). The Explanatory Memorandum to the Bill which later became that Act stated that: The effect of sections 36B and 36C is to extend to State and Northern Territory Attorneys-General the same entitlement to claim public interest privilege in proceedings before the Tribunal as the Commonwealth Attorney-General currently has, except that the grounds available to the States and the Northern Territory will not include the ground of prejudice to the security, defence or international relations of Australia. 51 The Tribunal said, at [75], there was nothing in the Parliamentary record at any point to suggest that broadening the entitlement to make a statutory claim for public interest immunity to the answering of questions and extending similar statutory entitlements to the State and Northern Territory Attorneys-General might revive any entitlement in others to claim "what used to be known as Crown Privilege". 52 The Tribunal said that s 36(5) of the Administrative Appeals Tribunal Act as it was in 1975 had been amended and relocated. It now referred to both s 36 and also s 36B in consequence of the more recent entitlement of State Attorneys-General to claim a like statutory immunity as can the Commonwealth Attorney-General. In those terms it now appears as s 36D(6). However there was nothing in the Parliamentary record to suggest that its relocation was intended to revive common law public interest immunity in the Tribunal. 53 For that reason, the Tribunal said at [77], it thought it wrong to accept the reasoning in Hobart Central Child Care and the oral submissions on behalf of the Minister which relied on the fact that, while s 36D(6) explicitly refers to ss 36 and 36B, it does not make reference to ss 36A or 36C. In the Tribunal's view that was simply the consequence of the entitlement to intervene on public interest grounds having been conferred on the Commonwealth and State Attorneys-General by ss 36 and 36B respectively. The Tribunal expressed the opinion that ss 36A and 36C (as the headings to each confirmed) were further manifestations of that entitlement. 54 At [79], the Tribunal said that, in its view, there was nothing in the text or context of s 36D(6) as it is now expressed to support the conclusion that in some manner it works to open a gap which the common law of public interest immunity might fill. 55 At [86], the Tribunal said it could not undertake its function unless the materials upon which the original decision-maker relied were available to the Tribunal. If common law public interest immunity existed it would prohibit the adducing of some materials, notwithstanding that any sensitivity could otherwise be protected by orders of the kind crafted by Brennan J in Re Pochi. 56 At [88], the Tribunal said it was of the view that there was no basis for it to apply a residual common law test to exclude from its consideration any part of those materials or other materials produced on summons unless the Attorney-General of the Commonwealth or a State issues a certificate under ss 36 or 36B to require the material to be dealt with other than in the way provided for in s 35. In reaching its conclusion it had regard to the text, scope and policy of the Administrative Appeals Tribunal Act read as a whole together with the relevant accompanying Explanatory Memorandums and other extrinsic materials. 57 The Tribunal concluded as follows: [90] We are satisfied that the Tribunal, if it can permit the testing of the evidence of Detective Inspector Cadden while practically protecting any answers which might prejudice law enforcement, it should do so. That is not only because of obligations of procedural fairness (limited as we accept those obligations must necessarily be in the circumstances of this review) as it applies to the Applicant. It is also because of the inherent risk to the interests of the Respondent if we were to be persuaded by Mr James to give little or no regard to what then would be the entirely untestable propositions upon which Detective Inspector Cadden's letter that asserts his belief that the Applicant was and remains a major figure in NSW organised crime is premised. The Tribunal does not merely 'hold the ring' between the parties. It may exercise its own inquisitorial powers in discharge of its public duty to reach the correct or preferable decision. [91] That is not to suggest that the interests of law enforcement, in the confidentiality of information relating to informers as referred to in the affidavit of support sworn by Assistant Commissioner of Police Mr Max Mitchell, should be given less than the most serious attention. It is simply to conclude that any protection of those interests must be secured by the Tribunal by reference to its statutory powers and duties under the AAT Act and not by reference to the common law. [92] We would ask counsel to confer with each other and Ms Sharp before tomorrow morning to ascertain if the terms of an agreed direction under s 35 of the AAT Act can be settled by consent together with a revised and strict timetable to permit these proceedings to be concluded within the 5 days for which the parties and the Tribunal have made arrangements. [93] As presently minded, but subject to hearing from the parties, the Tribunal is of the view that cross-examination of Detective Inspector Cadden on issues relating to the provenance and reliability of the information supplied to the police, but not as to the individual names of informants, may be permitted in the absence of the Applicant provided that counsel give undertakings that any information so disclosed will not be communicated to the Applicant or any other person unless the Tribunal or a court exercising judicial review otherwise orders. We would exclude all other legal representatives and observers other than Ms Sharp. We would grant Ms Sharp leave to continue to represent the Police Commissioner on the terms previously agreed, restricted to submissions relating to the adducing of evidence. [94] We are also minded, notwithstanding the practical challenges of accurate note taking, that the Tribunal cannot provide transcription for the closed proceedings. While the Tribunal is confident of the capacity of its contracted suppliers to meet ordinary obligations of confidentiality for the transcription services it supplies we do not think that may be adequate security for what may be highly sensitive information. We would want any notes counsel might take of the evidence or submissions to be collected at the conclusion of the closed hearing and placed in a sealed envelope to be retained with the file. Such notes are to be subject to an order that they not be released to any person unless the Tribunal or a court exercising judicial review otherwise orders. The only staff we would permit to remain during the closed session to assist the Tribunal would be the President's Associate. [95] We are of the view that in preparing the timetable for the balance of these proceedings a time limit of no more than 1 hour should be allowed for this procedure. That time should incorporate submissions on reliability so that closing addresses need not do more than refer to such matters other than by reference and in the generality. (Footnotes omitted.)

The submissions of the parties 58 The applicant, the New South Wales Commissioner of Police, submitted that the Tribunal had failed to give proper effect to the rule of statutory construction referred to as the principle of legality and in so doing failed to construe correctly the relevant provisions of the Administrative Appeals Tribunal Act. Secondly, the applicant submitted, the Tribunal failed to take into account the fact that public interest immunity also applied to executive agencies. The applicant relied on Jacobsen v Rogers [1995] HCA 6; 182 CLR 572 for both these propositions. The applicant submitted the Tribunal wrongly relied upon s 130 of the Evidence Act in discerning an intention to exclude common law public interest immunity in the Tribunal. The applicant submitted the Tribunal misunderstood the decision in Re Pochi. 59 The second respondent, the Minister, broadly supported the submissions made on behalf of the New South Wales Commissioner of Police. 60 The first respondent, Mr Guo, submitted that s 36D(6) of the Administrative Appeals Tribunal Act was an unequivocal expression of the legislative intent that any rules prohibiting the disclosure of information, in the public interest, were to be excluded. There was simply no room for the principle of legality to operate in favour of the retention of common law rules requiring the exclusion of material. The statutory language evidenced the necessary intention to abrogate public interest immunity. Mr Guo also submitted that, apart from the terms of s 36D(6), the doctrine of public interest immunity, as applied in the courts, would not apply to the current proceedings before the Tribunal. Reference was made to the reasoning in Applicant VEAL of 2002 v Minister for Immigration and Multicultural and Indigenous Affairs [2005] HCA 72; 225 CLR 88 at [23]-[26]. It followed that the Tribunal has the duty to enquire, for itself, in order to arrive at the correct or preferable decision. It also followed, Mr Guo submitted, that Jacobsen v Rogers was of little assistance. Mr Guo submitted that Re Pochi stood for the proposition that the common law principles, as applicable in courts, do not apply to the Tribunal. In the absence of a certificate from an Attorney-General, Mr Guo submitted, the Tribunal was at liberty, as it had done here, to fashion its procedure to afford protection to both the public interest in the protection of the information and the public interest in the person affected being afforded procedural fairness. Mr Guo submitted that the common law principles applicable to judicial proceedings simply did not apply to the Tribunal. Accordingly, it did not matter whether s 36D(6) referred only to ss 36 and 36B and not also to ss 36A and 36C.

Consideration 61 It is necessary first to identify the nature of public interest immunity. As explained by the High Court in Jacobsen v Rogers, public interest immunity reflects public policy in the same way that legal professional privilege does. The principles of legal professional privilege were described at 589 as "a basic law doctrine" which is not to be abrogated except in the clearest of terms (referring to Baker v Campbell [1983] HCA 39; 153 CLR 52). The plurality considered that public interest immunity was also a basic common law doctrine and not a mere rule of evidence. The plurality said, at 589: In Baker v Campbell, this Court held by a majority that the doctrine of legal professional privilege is not confined to judicial and quasi-judicial proceedings and extends to the compulsory disclosure of communications in extrajudicial proceedings. In particular, it was held to extend to search and seizure under a warrant issued pursuant to s. 10 of the Crimes Act. The majority referred to the principle that a basic common law doctrine is not to be abrogated except in the clearest of terms and held that s. 10, being silent upon the matter, did not exclude the doctrine of legal professional privilege. Public interest immunity reflects public policy as does legal professional privilege, although it has never been thought to be confined to judicial and quasi-judicial proceedings. In accordance with the approach adopted in Baker v Campbell, it is open to the Crown to resist the seizure under a s. 10 search warrant of documents to which public interest immunity attaches. As is demonstrated by Baker v Campbell and by this case, if a dispute arises as to the existence of the immunity, means are available to obtain a judicial determination of the issue. In any event, practical difficulties in giving effect to the immunity in the context of the execution of a search warrant would seem to us to be an inadequate reason for holding the doctrine to be inapplicable. Such practical difficulties as exist are not insurmountable. That is demonstrated by the guidelines agreed in 1986 between the Australian Federal Police and the legal profession on the execution of search warrants on lawyers' premises where a claim of legal professional privilege is made. (Footnotes omitted.) 62 We therefore approach the question of statutory construction in accordance with the principle of legality, that is, very clear words are required to exclude such a common law doctrine: see, by way of example: Potter v Minahan [1908] HCA 63; 7 CLR 277 at 304; Coco v The Queen [1994] HCA 15; 179 CLR 427 at 437-438; Re Minister for Immigration and Multicultural Affairs; Ex Parte Miah [2001] HCA 22; 206 CLR 57; X7 v Australian Crime Commission [2013] HCA 29; 248 CLR 92 at 153 [158] per Kiefel J; North Australian Aboriginal Justice Agency Ltd v Northern Territory [2015] HCA 41; 326 ALR 16 at [11] per French CJ, Kiefel and Bell JJ and [222] per Nettle and Gordon JJ. 63 Applying that principle of construction, it may be accepted that ss 36 and 36B "exclude the operation of any rules of law that relate to the public interest", being the words of s 36D(6) but those words are immediately followed in the subsection by the words "and would otherwise apply in relation to the disclosure of information, or a matter contained in documents" in proceedings before the Tribunal. 64 In our opinion, it is significant, in terms of the text and context provided by these provisions, that s 36 applies to the disclosure of information or the disclosure of any matter contained in a document, as does s 36B, but neither of those sections deals with answering questions at the hearing of a proceeding before the Tribunal. The sections which do deal with answering questions are s 36A in the case of the Commonwealth and s 36C in the case of a State. As may be seen, s 36D(6) has nothing to say to those provisions. 65 We have referred above to the reliance placed by the Tribunal on Re Pochi, which Brennan J decided in 1979. That case was determined not on the basis of public interest immunity but rather on the basis of formulating appropriate confidentiality orders under s 35 of the then Administrative Appeals Tribunal Act. It is significant to note that at the relevant time that Act did not contain the series of detailed provisions, inserted in 1988, dealing with certain public interest immunity claims by both the Commonwealth and the States. In 1979, it did, however, contain s 36 which dealt with the process to apply, including the role of the President (a Federal Court judge), if the Commonwealth Attorney-General certified that disclosure of information or documents would be contrary to the public interest on specified grounds. Section 36A was also in the Administrative Appeals Tribunal Act at that time and it dealt with a person answering questions in the course of giving evidence and the Attorney-General objected on the ground of public interest immunity. These provisions appear to have been based on an assumption that a public interest immunity claim could not otherwise be resolved within the Tribunal (see the reference in s 36(1)(c) to "a judicial proceeding"). In our opinion Brennan J proceeded on the basis that public interest immunity did not operate except in a court and did not apply in proceedings before the Tribunal, see especially at 512 of the report. Jacobsen v Rogers had not then been decided by the High Court. It is also notable that in a decision of the Full Court which also preceded Jacobsen v Rogers, Aboriginal Sacred Sites Protection Authority v Maurice (1986) 10 FCR 104, Bowen CJ said at 108 that it was "not entirely clear" whether public interest immunity applied to proceedings other than court proceedings. See also the dissenting judgment of Brennan J in Jacobsen v Rogers. 66 In our opinion, common law public interest immunity has not been displaced by the relevant provisions of the Administrative Appeals Tribunal Act relating to oral evidence. 67 We refer to the terms of ss 36(1) and (5) as originally enacted. The former provision provided that if the Commonwealth Attorney-General gave a certification, the following provisions in s 36 had effect. Subsection 36(5) provided that: "This section excludes the operation of any rules of law relating to the public interest that would otherwise apply in relation to the disclosure of information or of the contents of documents in proceedings before the Tribunal". The reference to "this section" necessarily imported s 36(1) which, in its terms, was confined to the situation where the Attorney-General gave a certificate. The provision was silent on the question of whether public interest immunity applied where no such certificate was given. Necessarily therefore, from the outset, any displacement of public interest immunity by the Administrative Appeals Tribunal Act was relatively limited. Although that was broadened by subsequent amendments, for the reasons given above those amendments did not have the effect of displacing common law public interest immunity in respect of oral evidence. 68 Re Suardana & Minister for Immigration & Ethnic Affairs (1980) 2 ALD 830; 49 FLR 8 was a case where, in respect of various exhibits, the Attorney-General certified that it would be contrary to the public interest to disclose the names of the informants in those documents as that disclosure would interfere with the effective detection and prevention of criminal offences in relation to drugs and which reason could form the basis for a claim by the Crown in right of the Commonwealth in a judicial proceeding. It may be noted that this decision was subsequent in time to the enactment of, but did not involve, s 36A of the Administrative Appeals Tribunal Act. The President, Davies J, considered the information in accordance with ss 36(3) and 36(4). 69 In Re Queensland Nickel, Gray J was dealing with an application for discovery of documents from the state of Queensland. Queensland had become a party to the proceedings. In resisting the application, the Solicitor-General for the state of Queensland appeared and relied on a certificate of the Attorney-General for the state of Queensland pursuant to s 36B. The certificate made claims in respect of certain documents and information in documents. Gray J said as follows: (10) It is plain from s 36D(6) that s 36B is intended to operate as a code, whenever an Attorney-General of a state certifies in terms of subs (1). Any common law rule is specifically excluded by s 36D(3)-(6). (11) Nevertheless, regard must be had to the common law in at least one respect. The operation of s 36B so far as subs (1)(b) is concerned, depends upon the existence of a certified reason that could form the basis for a claim by the Crown in right of the state in a judicial proceeding that information or matter contained in a document should not be disclosed. It is necessary to look to the common law, to ascertain when such a claim could be made in a judicial proceeding. There can be no doubt that s 36B(1)(b) is intended to specify that immunity from disclosure of the contents of documents which used to be known as Crown privilege, but has become known as public interest immunity. The nature of this immunity, and the principles to be applied in determining whether it exists are conveniently set out in a passage in the judgment of Gibbs ACJ in Sankey v Whitlam (1978) 142 CLR 1 at 38- 46. For the purposes of this proceeding, the important point is that s 36B(1)(b) can only be invoked in circumstances in which public interest privilege could have been claimed, were the proceeding a judicial one. That immunity can be claimed whether or not the Crown is a party to a particular proceeding, if the Crown is called upon to produce documents. In circumstances in which the Crown is a party to an application before the tribunal, and in which it has available to it the privileges of a private litigant, such as the privilege of refusing to divulge communications with its legal advisers, or communications made without prejudice, the section does not have any operation with respect to those privileges. (12) Once a claim for immunity has been determined to fall within s 36B(1)(b), the principles upon which it is to be determined are laid down by s 36B(5). These principles may well differ from those which would apply under the common law in a judicial proceeding … In our opinion, Re Queensland Nickel does not deal with the present question which arises in relation to oral evidence and where the Attorney-General is not otherwise a party and has not certified. 70 For completeness, we note the observations of French J, as his Honour then was, in Re Grant & Australian & Overseas Telecommunications Corp (1992) 16 AAR 66, to which we were taken. That case concerned a summons to the Vietnam Veterans' Counselling Service to produce certain documents. The Attorney-General for the Commonwealth signed a certificate pursuant to s 36(1) stating that the disclosure of matters specified in the summons was contrary to the public interest because it would severely inhibit the effectiveness of the Service from operating as a confidential counselling service and any breach of confidentiality of the Service would inhibit its effectiveness. Thus, the decision does not deal with the present question of oral evidence. We refer to it insofar as French J said that s 36D(6) in a sense may be seen as a rule for the interpretation of s 36 and did not of its own force exclude the operation of such rules of law, but that s 36 had that effect. French J cited Re Queensland Nickel to the effect that the equivalent of s 36 in relation to State Attorneys-General, s 36B, was intended to operate as a code. His Honour said that the practical operation of s 36D(6) was hard to envisage. It did not prevent a consideration under s 36(4) of a wide range of factors related to the immunity question. 71 We have also referred above to the reliance placed by the Tribunal upon s 130 of the Evidence Act \in concluding that public interest immunity was no longer a substantive rule of law, but rather is a rule of evidence. This reasoning was used to distinguish Jacobsen v Rogers. In [42] of the Tribunal's reasons for decision, it was said that, by enacting s 130 of the Evidence Act, the Parliament was "resolving" the dispute whether public interest immunity was a common law doctrine by characterising it as a rule of evidence. In our respectful opinion, the Tribunal failed to appreciate the limited nature of s 130 of the Evidence Act and its non-application to pre-trial steps prior to evidence being adduced in curial proceedings, such as discovery and notices to produce: (see, Esso Australian Resources Ltd v Commissioner of Taxation [1999] HCA 67; 201 CLR 49). This limitation has been overtaken in some State and Territory evidence legislation (see s 131A) but not at the Commonwealth level. There has never been any doubt that public interest immunity has effect in a court and is therefore a rule of evidence. Thus, the Evidence Act only applies to proceedings in a Federal Court or in a body which is required to apply the rules of evidence (see s 4). To say that, however, is to say nothing about public interest immunity outside a court as a substantive rule of law. 72 In our opinion, when the matter of oral evidence where there is a claim to public interest immunity is analysed by reference to the principles that public interest immunity is a basic common law doctrine and not merely a rule of evidence; and that public interest immunity applies to bodies other than courts, including the Tribunal; and, that in accordance with the principle of legality, words of irresistible clarity are required to exclude such a common law doctrine, the provisions in the Administrative Appeals Tribunal Act relied upon by the Tribunal do not rise to that level. As we have said, notably s 36D(6) does not apply to s 36C and we do not construe s 36C as excluding a claim to public interest immunity. Furthermore, there is no other indication that s 36C was intended to preclude anyone other than the State Attorney-General from claiming public interest immunity, whether it be the Tribunal itself or another State agency, such as the Commissioner of Police. 73 In light of this conclusion, since the application before the Court concerned only oral evidence, it is not necessary for us to consider whether s 36C operates as a code, in the sense that it operates only where an Attorney-General of a State informs the Tribunal of his or her opinion. 74 It is also appropriate to question the practicality of the Tribunal's approach in relation to oral evidence. If it be the case that only the Attorney-General of the State can give a certificate in the circumstances envisaged in s 36C, it would mean that whenever an issue of public interest immunity arose in relation to oral evidence in a case to which the Attorney-General is not a party, an adjournment may well be needed to enable the Attorney-General to be notified and given time to consider whether a certificate should issue. There would be considerable practical inconvenience in having the Attorney-General attend every hearing in which it was feared that a public interest immunity issue might arise, even allowing for the fact that s 36(7) contemplates that the Attorney-General can appear through a legal representative or some other person. 75 As we have noted, Mr Guo relied on Applicant VEAL of 2002 at [23]-[26]. In our opinion that authority does not stand for the proposition that public interest immunity does not apply in the Tribunal. The High Court was dealing with procedural fairness in the Tribunal and indicating how the Tribunal might mould its procedures, by analogy with the courts' accommodation of public interest immunity, so as to afford procedural fairness consistently with ensuring that information that had been supplied by an informer was not denied to the Executive government when making its decision. It is not at all clear that the letter making allegations against the appellant could have been the subject of a claim to public interest immunity. What is clear is that no such claim is identified in the unanimous judgment of the High Court. 76 We note that the parties to the application accepted the correctness of the decision of the Full Court in Australian Securities and Investments Commission v P Dawson Nominees Pty Ltd [2008] FCAFC 123; 169 FCR 227 at [23]-[24] where it was held that a balancing exercise was required even in a claim based on protecting an informer's identity and that there was "no point in attempting categorisation [of the public interest] into different levels of importance". 77 We also note for completeness that although notices under s 78B of the Judiciary Act were sent to the Attorneys-General, at the suggestion of the Court, directed to: (a) the legislative power of the Commonwealth Parliament to enact ss 33, 35, 36, 36A, 36B, 36C, 36D, 37 and 39 of the Administrative Appeals Tribunal Act 1975 (Cth); and (b) whether as a matter of construction of those provisions the Tribunal is authorised to regulate the manner in which a claim to public interest immunity by the Commissioner of Police (NSW) may be maintained in the Tribunal and to require answers the subject of such a claim by the Commissioner of Police (NSW) to be given to the Tribunal neither the applicant Commissioner nor any Attorney-General sought to raise such an issue, whether by reference to Melbourne Corporation v Commonwealth [1947] HCA 26; 74 CLR 31 or otherwise, before this Court. Indeed, counsel for the applicant Commissioner accepted that the State of New South Wales was in no different position to the Commonwealth so far as concerned the issue of displacement or modification of public interest immunity. Counsel for the applicant Commissioner was content for the Court to proceed directly from the construction of the provisions of the Administrative Appeals Tribunal Act so far as they concern the Commonwealth executive, to apply that same construction to the provisions so far as they concern the State.

Relief 78 In our opinion, the application should be allowed and the decision of the Tribunal quashed. The matter should be remitted to the Tribunal for determination according to law. This means that any claim to public interest immunity should be decided by the Tribunal in accordance with common law principles: if the claim is upheld then the Tribunal would either reject the question or not require the question to be answered. No issue therefore arises about the Tribunal using such oral evidence because the evidence will not have been given. 79 We see no need for an injunction. Given the terms of the decision of the Tribunal, which will be set aside, we see no need for declaratory relief. It is to be noted that this Court was not asked to, and has not, formed any view on whether any claim for public interest immunity could be sustained in fact. The answer to that question will depend on what questions are asked of the witness or witnesses, what claims for public interest immunity are made and the evidence in support of those claims. The parties were also agreed that it was unnecessary for the Court to determine broader issues regarding public interest immunity and the production of documents and we have not done so. The first respondent should pay the applicant's costs. There should be no order for costs in relation to the second respondent. The public interest immunity question is a separate lis from the application to which the Minister is a respondent: Young v Quin (1985) 4 FCR 483 per Bowen CJ at 485-486. Consistently with that analysis, the Minister did not ask for costs. I certify that the preceding sixty (60) numbered paragraphs are a true copy of the Reasons for Judgment herein of the Honourable Justices Robertson and Griffiths.