Polyukhovich v The Commonwealth of Australia

In *Polyukhovich v The Commonwealth of Australia*, the applicant, Ivan Timofeyevich Polyukhovich, sought to challenge the constitutional validity of the *War Crimes Act 1945* (Cth) and its application to him. The case came before the Full Court of the High Court of Australia.

The central legal issues before the Court included whether the *War Crimes Act* operated retroactively in a manner that was inconsistent with international law, specifically concerning acts alleged to have occurred during World War II. The applicant also raised arguments regarding the scope of Australia's external affairs power, the implications of Chapter III of the Constitution, and the appropriate jurisdictional remedies available. Furthermore, the Court was required to consider whether relevant international obligations or concerns had been sufficiently established on the facts to enliven these constitutional powers.

The applicant's submissions, as outlined by counsel, aimed to establish propositions regarding the retroactivity of international law and the definition of crimes against humanity as contemplated in 1945. Counsel intended to address changes in international law post-World War II, the method of proving customary international law, and the proper construction and operation of the *War Crimes Act*. The arguments also focused on the Act's alleged conflict with Australia's international obligations and its unconstitutionality under the external affairs power and Chapter III. The applicant also contended that extradition, rather than domestic prosecution under the Act, might be the appropriate remedy.