Chu Kheng Lim v Minister for Immigration, Local Government and Ethnic Affairs

The plaintiffs, Chu Kheng Lim and others, sought release from immigration detention. They were detained under provisions of the *Migration Act 1958* (Cth) pending the determination of their immigration status. The Minister for Immigration, Local Government and Ethnic Affairs and others were the defendants. The matter came before the Full Court of the High Court of Australia.

The central legal issues before the Court were the validity of certain provisions of the *Migration Act 1958* (Cth), specifically sections 54L, 54N, and 54R, in relation to the plaintiffs' applications for release from custody. The Court was also asked to consider whether, if these sections were invalid, the defendants had a legal duty to consider the plaintiffs' release applications in light of international human rights instruments.

The High Court held that sections 54L and 54N of the *Migration Act* were valid. However, section 54R was found to be invalid. The Court's reasoning, delivered by Mason CJ, Brennan, Deane, Toohey, Gaudron, and McHugh JJ, focused on the constitutional division of powers and the nature of judicial power. They determined that section 54R, by purporting to prevent courts from ordering the release of certain non-citizens, impermissibly encroached upon the judicial power of the Commonwealth, which is vested in the courts by Chapter III of the Constitution. The Court concluded that the power to detain or release individuals is a matter for the executive, but the courts retain the power to review the legality of detention. As section 54R sought to remove this fundamental judicial oversight, it was invalid. The questions concerning the duty to consider international conventions did not arise due to the invalidity of section 54R.