By: Richard Leder OAM, Blake Pappas and Deniz Coskundag

AB (A Pseudonym) & Anor v Independent Broad-Based Anti-Corruption Commission [2024] HCA 10

At a glance

  • On 13 March 2024, the High Court of Australia delivered a judgment involving IBAC’s obligations under s 162(3) of the IBAC Act 2011 (Cth) regarding the disclosure of “adverse material”.
  • The case revolved around the proper construction of s 162(3) and the extent of IBAC’s obligation to provide evidentiary material to affected parties so they can adequately respond to adverse comments or opinions.
  • The High Court partly upheld the appeal and clarified the term “adverse material” as being any evidentiary material IBAC relies on in its special report to justify a comment or opinion that is adverse to any person.
  • The Court also found that IBAC complied with the legislation by providing an undertaking not to transmit its draft report to the Parliament of Victoria.


Between 2019 and 2021, the Independent Broad-based Anti-corruption Commission (IBAC) conducted an investigation into allegations of unauthorised access to, and disclosure of, internal email accounts of CD (a public body and the second appellant). As part of its investigation, IBAC gathered information and conducted private examinations of witnesses.

During the investigation, IBAC provided AB (a senior officer and employee of the second appellant) with a redacted version of its draft special report and requested his response. The draft report contained proposed findings that were adverse to the appellants, which involved unauthorised access and disclosure of information. AB then requested the documents that IBAC relied on to support the adverse findings.

IBAC provided AB with the transcript of his private examination, which was conducted during the investigation, but refused to provide AB with the transcripts of other witness examinations on the basis of confidentiality.

On 3 February 2022, AB commenced proceedings in the Victorian Supreme Court. He argued that IBAC had failed to comply with s 162(3) and stated that he had been denied a reasonable opportunity to respond to the adverse material. AB also sought an injunction prohibiting IBAC from publishing the draft report.

The primary judge, Ginnane J, found that the redacted version of the draft report did “contain the substance of the adverse material upon which the adverse comments or opinions about the [appellants] contained in it were based.”1 Further, His Honour accepted that IBAC provided the appellants with the “substance or gravamen of the adverse material.”2 His Honour also found that as IBAC had given the appellants the opportunity to provide their response to the draft report, IBAC had satisfied its obligations under s 162(3) through that right of response.3

The appellants sought leave to appeal to the Court of Appeal, contending that the primary judge erred in finding that “the draft report contained the substance and gravamen of the adverse material”4 in line with IBAC’s obligation under s 162(3).

The application for leave to appeal was refused and the Court of Appeal rejected all grounds of appeal, which contended non-compliance with s 162(3).5 In finding that IBAC had complied with s 162(3), the Court of Appeal ruled that the primary judge erred in construing the phrase “adverse material.”6 Their Honours held that “adverse material” referred to adverse comments or opinions that IBAC proposed to publish in its draft report, and not the material on which the comments or opinions were based.7

Issue before the High Court

Section 162(3) of the IBAC Act provides that if IBAC intends to include a comment or an opinion that is adverse to a person in a report, it must first provide the person with a “reasonable opportunity” to respond to the “adverse material” and set out each element of the response in its report.

The key issue before the High Court was whether “adverse material”, as referred to in s 162(3), is interpreted as the proposed adverse comments or opinions in the draft report or whether it is the evidentiary material those proposed adverse comments or opinions are based on.


The High Court upheld the appellants’ ground of appeal on the construction of s 162(3). The High Court determined that the Court of Appeal erred in its construction of “adverse material” and clarified that the correct interpretation of “adverse material” under s 162(3) refers to evidentiary material IBAC says justifies an adverse comment or opinion.

However, the Court found that the Court of Appeal was correct to find that IBAC had complied with s 162(3), subject to an exception. The exception involved an IBAC undertaking to the Court that it would not transmit a report containing the one adverse comment or opinion to the Parliament of Victoria, and that the comment or opinion would be removed.

While the appellants were not afforded any relief, IBAC was ordered to pay the appellants’ costs of the High Court appeal.


This High Court ruling sheds light on the importance of upholding procedural fairness in governance and regulatory processes by clarifying the rights of individuals, government entities and their employees when responding to IBAC requests.

The High Court has concluded that the term “adverse material” includes evidentiary material that is used by IBAC to justify a comment, or form an opinion, that is adverse to a party. Those subject to adverse findings will now have the opportunity to review the documents that lead IBAC to an adverse comment or opinion and be given an opportunity to respond sufficiently.

[1] AB (a pseudonym) v Independent Broad-based Anti-corruption Commission [2022] VSC 570 at [168] per Ginnane J.

[2] Ibid, at [151], [154] per Ginnane J.

[3] Ibid, at [175]-[176], per Ginnane J.

[4] AB [2022] VSCA 283 at [104] per Emerton P, Beach and Kyrou JJA.

[5] AB [2022] VSCA 283 at [159] per Emerton P, Beach and Kyrou JJA.

[6] Ibid, at [126] per Emerton P, Beach and Kyrou JJA.

[7] Ibid.