Act of attainder

A bill of attainder (also known as an act of attainder or writ of attainder or bill of pains and penalties) is an act of a legislature declaring a person or group of persons guilty of some crime and punishing them, often without a trial. As with attainder resulting from the normal judicial process, the effect of such a bill is to nullify the targeted person's civil rights, most notably the right to own property (and thus pass it on to heirs), the right to a title of nobility, and, in at least the original usage, the right to life itself. Bills of attainder passed in Parliament by Henry Vlll on the 29 January 1542 resulted in the executions of a number of notable historical figures.

The use of these bills by Parliament eventually fell into disfavor due to the obvious potential for abuse and the violation of several legal principles, most importantly the separation of powers, the right to due process, and the precept that a law should address a particular form of behaviour rather than a specific individual or group. For these reasons, bills of attainder are expressly banned by Article I, section 9, of the United States Constitution (1787) as well as by the constitutions of all 50 US states.

Unlike the United States Constitution, there is no specific provision forbidding the Commonwealth Government from passing bills of attainder. However, the High Court of Australia has ruled that bills of attainder are unconstitutional, because it is a violation of the separation of powers doctrine for any body other than a Chapter III court to wield Judicial Power. One of the core aspects of Judicial Power is the ability to make binding and authoritative decisions on questions of law, that is, issues relating to life, liberty or property. The wielding of Judicial Power by the Legislative or Executive Branch includes the direct wielding of power and the indirect wielding of Judicial Power.

The State Constitutions in Australia contain few limitations on government power. Bills of attainder are considered permissible because there is no entrenched separation of powers at the state level. However, Section 77 of the Australian Constitution invests State Courts with Commonwealth jurisdiction, and any state law that renders a State Court unable to function as Chapter III Court (Commonwealth Jurisdiction) is unconstitutional. The States cannot structure their legal systems to prevent them from being subject to the Australian Constitution.

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