Minister for Immigration v NZYQ

Sections 189(1) and 196(1) of the Migration Act 1958 (Cth) cannot validly authorise the executive detention of an unlawful non-citizen where there is no real prospect of removal from Australia becoming practicable in the reasonably foreseeable future, because such detention then ceases to serve a legitimate non-punitive purpose and breaches the constitutional limit (Lim) that only a court may impose punitive detention.