Ex Post Facto Law

/ɪks pɒst ˈfæk.toʊ lɔː/

Definitions

  1. (n.) A law that retroactively changes the legal consequences of actions committed before its enactment, typically prohibited in criminal law.
    The court struck down the statute as an unconstitutional ex post facto law.

Forms

  • ex post facto law
  • ex post facto laws

Commentary

Ex post facto laws are generally forbidden in criminal law to protect individuals from retrospective punishment; care is needed to distinguish this from permissible retroactive civil legislation.

This glossary is for general informational and educational purposes only. Definitions are jurisdiction-agnostic but reflect terminology and concepts primarily drawn from English and American legal traditions. Nothing herein constitutes legal advice or creates a lawyer-client relationship. Users should consult qualified counsel for advice on specific matters or jurisdictions.

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Amicus Docs | Ex Post Facto Law Definition