act of attainder

exercise of power; act which is done; performance; process of doing

A bill of attainder (also known as an act or writ of attainder) is an act of legislature declaring a person or group of persons guilty of some crime, and punishing them, without benefit of a trial. The United States Constitution forbids both the federal and state governments to enact bills of attainder, in Article 1, Sections 9 and 10, respectively. It was considered an excess or abuse of the British monarchy and Parliament. They were abolished in the United Kingdom in 1870.
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