Minister for Home Affairs v Administrative Appeals Tribunal

The Minister for Home Affairs sought judicial review of a decision made by the Administrative Appeals Tribunal (AAT) concerning the review of visa cancellation decisions. The core of the dispute revolved around the AAT's power to affirm a decision that the Minister argued was invalid from its inception. Smith J of the Federal Court of Australia presided over this matter.

The central legal question before the Court was whether the AAT possessed the statutory power to review and affirm a visa cancellation decision that was alleged to be invalid. Specifically, the Court had to determine the scope of the AAT's jurisdiction under the relevant migration legislation when faced with a cancellation decision that might be a nullity.

Smith J reasoned that the AAT's power to review a "decision" under the Migration Act 1958 (Cth) presupposes the existence of a valid decision to review. If a purported decision is a nullity, it has no legal effect, and therefore, there is no "decision" for the Tribunal to affirm. Consequently, the AAT lacked the power to affirm the cancellation decision in question. The Court concluded that the Tribunal had acted outside its jurisdiction by attempting to affirm a decision that was a nullity.

The Court made directions regarding the future conduct of the proceedings.