MJZP v Director-General of Security

The plaintiff, MJZP, sought a declaration from the High Court of Australia that section 46(2) of the *Administrative Appeals Tribunal Act 1975* (Cth) was invalid as it infringed Chapter III of the Constitution. This provision requires the Federal Court to take all necessary steps to prevent disclosure of certain matters, contained in documents certified by the ASIO Minister as contrary to the public interest, to anyone other than the court members constituted for the proceeding. The plaintiff argued that this requirement compelled the Federal Court to depart from the general rule of procedural fairness more than was reasonably necessary to protect a compelling and legitimate public interest.

The High Court was required to determine whether section 46(2) of the *Administrative Appeals Tribunal Act 1975* (Cth) was invalid on the grounds that it infringed Chapter III of the Constitution. This involved considering whether the previous High Court decision in *SDCV v Director-General of Security* (2022) 277 CLR 241, which upheld the validity of section 46(2), should be re-opened and overruled. The court also had to consider who should bear the costs of the special case and the proceeding.

The Court concluded that the principal submission of the Commonwealth, that *SDCV* provided a complete answer to the plaintiff's case and should not be re-opened, was correct. The majority in *SDCV* had held that section 46(2) was valid in its entirety, finding that the arguments for its invalidity involved a "fatal artificiality" and that the provision did not impose any practical injustice. While acknowledging that at lower levels of generality the decision in *SDCV* lacked a clear ratio decidendi, the Court determined that a clear restatement of the ratio would have to await another case. Consequently, the Court answered the questions posed in the special case.

The High Court ordered that section 46(2) of the *Administrative Appeals Tribunal Act 1975* (Cth) is not invalid on the basis that it infringes Chapter III of the Constitution. The plaintiff was ordered to pay the costs of the Special Case and of the proceeding.