1. On 23 January 2025, the Applicant made an application to the Tribunal for review of the IC's decision.[1] The Applicant's review application was lodged out of time.
2. On 7 March 2025, the Respondent filed and served the Tribunal documents pursuant to s 23 of the Administrative Review Tribunal Act 2024 (ART Act).
3. On 10 July 2025, the Tribunal made an order under s 19(2) of the ART Act extending the time for making the application to 23 January 2025. The Respondent did not oppose the making of that order. The Tribunal did not seek the views of the Other Party when making its decision, as it had not informed the Other Party that they were a party to the proceedings.
4. On 31 October 2025, the Other Party was first advised by the Respondent's representative that they were a party to the proceedings.
5. On the same day, 31 October 2025, the Respondent's representative also wrote to the Applicant requesting that he apply for a stay of the IC decision to grant partial access to the documents.
6. On 12 December 2025, the Applicant made an application to the Tribunal to stay the effect of the IC's decision, to the extent that it requires the disclosure of information about them and involves issues for determination by the Tribunal in their application for review. The Applicant submits that a stay is necessary to preserve the subject matter of the review. They further submit that releasing the information would cause them significant professional, reputational, and financial harm.[2]
7. An interlocutory hearing was organised for 10 February 2026 to hear submissions in relation to the Applicant's application for a stay.
8. On 6 February 2026, the Other Party applied to the Tribunal to revoke the 10 July 2025 extension of time order on the basis that they had not been given the opportunity to make submissions in relation to that application.
9. Appearances at the interlocutory hearing were as follows: the Other Party was represented by Mr M Champion of Champions Lawyers; the Applicant appeared self‑represented; and the Respondent was represented by Ms L McConnell of the Australian Government Solicitor.
10. The Respondent's position was that it did not oppose either the extension of time or the making of a stay order.
11. Evidence before the Tribunal was an affidavit of David Champion (the Other Party) sworn on 4 February 2026. In his affidavit Mr David Champion states he was not informed of the proceedings until November 2025 and that if he had been made aware of the application for an extension of time, he would have opposed it.
12. At the hearing, Mr David Champion's representative submitted that the Tribunal clearly failed to afford him procedural fairness by not informing him of the proceedings, not notifying him of the leave application, and then granting leave without giving him an opportunity to be heard. Based on my review of the Tribunal's records, this appears to be correct.
13. The Tribunal was referred to the High Court's decision in Nathanson v Minister for Home Affairs & Anor [2022] HCA 26, where the Court unanimously held that a denial of procedural fairness was material and therefore constituted jurisdictional error. The majority explained that when a party is wrongly denied a fair chance to present their case, 'reasonable conjecture' does not require them to show exactly how they would have used that lost opportunity. The principle is that, if given a fair opportunity, a party will use it, and doing so could lead to a more favourable outcome.[3]
14. I consider that the threshold of materiality has been reached, the administrative error of the Tribunal deprived the Other Party the opportunity to present their case which could realistically have affected the outcome.

1. Section 86 of the ART Act provides that a power of the Tribunal to make an order includes the power to revoke or vary that order. The Administrative Appeals Tribunal Act 1975 (Cth) (AAT Act) contained no equivalent provision. The Revised Explanatory Memorandum to the Administrative Review Tribunal Bill 2024 explains that s 86 was included 'for the avoidance of doubt' to confirm that the Tribunal's power to make an order necessarily includes the power to revoke or vary it, whether the order is made under the ART Act or another enactment.[4]
2. Under the AAT Act, s 29(7) conferred power on the Tribunal to make orders to extend time for making an application, but did not expressly provide for the variation or revocation of such orders or directions. As a result, it was necessary to rely on s 33(3) of the Acts Interpretation Act 1901 (Cth), which provides:

(3) Where an Act confers a power to make, grant or issue any instrument of a legislative or administrative character (including rules, regulations or by‑laws), the power shall be construed as including a power, exercisable in the like manner and subject to the like conditions (if any), to repeal, rescind, revoke, amend or vary any such instrument.

3. Although the term 'instrument' is not defined in that Act, s 4 of the Legislation Act 2003 (Cth) defines it to mean 'any writing or other document, and includes an instrument in electronic form'.
4. In Poidevin and Australian Securities and Investments Commission [2020] AATA 782, President Justice Thomas and Deputy President Redfern concluded that an order or direction in that case under ss 35 or 41 of the AAT Act is an instrument of an administrative character. Consequently, s 33(3) of the Acts Interpretation Act operated to confer on the Tribunal the power to vary or revoke such orders.
5. The AAT Act, like the ART Act, also contained specific powers permitting the Tribunal to revisit its decisions. It expressly allowed reinstatement of an application where the applicant failed to appear, and reinstatement where an application had been dismissed in error. It further included a 'slip rule', empowering the Tribunal to correct an obvious error in the text of a decision or its written reasons.
6. Given these specific provisions, it is unsurprising that the drafters considered it prudent to include in the new Act an express power to vary or revoke orders, thereby avoiding any implication that the existence of specific remedial powers might limit the Tribunal's broader ability to amend or revoke its orders.
7. As such, s 86 of the ART Act removes any doubt about the Tribunal's authority to reconsider its decisions. In light of this, I do not consider it necessary to determine whether the Tribunal was functus officio. Given the circumstances outlined above, I am satisfied that the order made by the Tribunal on 10 July 2025 should be revoked.
8. At the hearing, I asked for submissions from the parties on whether an extension of time should have been granted by reference to the generally accepted principles in Hunter Valley Developments Pty Ltd v Minister for Home Affairs and Environment (1984) 3 FCR 322 (Hunter Valley).
9. As the Respondent noted, the question for the Tribunal is whether - even if the extension of time is revoked - would the same decision ultimately be made when the balancing exercise is undertaken?
10. Although it may be that the same order would be made, I consider that fairness to both the Other Party and the Applicant requires that they be given the opportunity to make full submissions.
11. At the hearing, the Other Party's representative made submissions on the Hunter Valley principles, but these were directed to supporting their argument that the extension of time should not have been granted in the first place.
12. Although the Respondent continued to indicate that it did not oppose the extension of time, I consider it necessary to reset the process so the Applicant's extension of time application can be appropriately considered. This approach ensures that all parties are afforded the opportunity to make the full submissions they would have provided had the Other Party been properly notified of the application.
13. The parties accepted that revoking the extension‑of‑time order rendered the second interlocutory matter redundant. At the hearing, I received submissions on the stay order because, if I were not to revoke the extension of time order, I did not wish to cause further delay in a matter that has been ongoing since 2019 by requiring the parties to return solely to address the stay application.
14. This now appears to have been a false economy. In my view, it is in the interests of all parties - particularly given the lengthy history of the matter - for the proceedings to advance on procedurally sound foundations.