Editing Polyukhovich v Commonwealth (section)

===Judicial power===
In relation to Polyukhovich's contention that the Act purported to usurp the judicial power of the Chapter III courts, the court held by a majority of 4 to 2 (Brennan J not deciding) that the statute did not invalidly usurp the judicial power of the Commonwealth. While the majority all accepted that a bill of attainder would offend the Commonwealth [[separation of powers]], the fact that a law operated ''[[Ex post facto law|ex post facto]]'' did not automatically make the law a bill of attainder. In addition, an ''ex post facto'' law of the kind under consideration was not a usurpation of judicial power.