Ex Post Facto(redirected from Ex-post facto)
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Ex Post Facto
Describing anything, especially a law, that is applied retroactively. For example, a law criminalizing a certain action, which was passed on November 20, 2010, but gives the state the power to prosecute offenders retroactively to January 1, 2010, is an ex post facto law. Many jurisdictions do not permit their governments to enact ex post facto laws, at least in criminal cases.