Extradition — Extradition Act 1988 (Cth) — Bilateral Extradition Treaty between Australia and Hungary — Treaty interpretation — Double criminality — Requirement that offence charged was crime at time of commission of offence — War crimes — Refusal of surrender

Extradition — Double criminality — Nature and scope of requirement — Temporal element — Whether acts constituting offence must have constituted the precise crime for which extradition requested at the date they took place — War crimes — Murder — Respondent accused of war crime of murdering civilian in Hungary in 1944 — Murder constituting offence under Hungarian law in 1944 — Offence of war crimes added to Hungarian law at later date

Treaties — Interpretation — Vienna Convention on the Law of Treaties, 1969 — Articles 31 and 32 — Whether declaratory of customary international law — Interpretation of treaty given effect by statute — Relevance of subsequent practice of the parties

Relationship of international law and municipal law — Treaties — Interpretation — Extradition treaty — Treaty given effect in Australian law by statute — Approach to treaty interpretation

War and armed conflict — War crimes — Extradition — Requirement of double criminality — War crime constituting offence of murder — The law of Australia