ex post facto law


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Related to ex post facto law: double jeopardy, writ of habeas corpus

ex post facto law

n.
A law that retroactively makes criminal an act that was not criminal at the time it was done. In the United States, the passage of such laws is forbidden by the Constitution.
References in classic literature ?
No State shall enter into any treaty, alliance, or confederation; grant letters of marque and reprisal; coin money; emit bills of credit; make any thing but gold and silver a legal tender in payment of debts; pass any bill of attainder, ex post facto law, or law impairing the obligation of contracts; or grant any title of nobility.
Bills of attainder, ex post facto laws, and laws impairing the obligation of contracts, are contrary to the first principles of the social compact, and to every principle of sound legislation.
No Bill of Attainder or ex post facto Law shall be passed.
No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility.
By a limited Constitution, I understand one which contains certain specified exceptions to the legislative authority; such, for instance, as that it shall pass no bills of attainder, no ex post facto laws, and the like.
No ex post facto law may be passed, the Bill of Rights guarantees.
An ex post facto law, the classic example of an objectionably retrospective rule, can operate precisely because it is a rule for future conduct that depends on past events: under an ex post facto law, officials are directed to impose criminal punishment on the basis of past events.
According to the Supreme Court of Missouri, an ex post facto law is one that "provides for punishment for an act that was not punishable when it was committed or that imposes an additional punishment to that in effect at the time the act was committed.
156) An ex post facto law is a criminal law that has a retroactive effect.
The Louisiana legislature is not only prohibited by the United States Constitution from passing any ex post facto law, but also by its own state constitution.
17) An ex post facto law is one that changes the legal consequences of an act after its execution, either by "impos[ing] a punishment for an act which was not punishable at the time it was committed; or impos[ing] additional punishment to that then prescribed.