Advanced Criminal Law My Outline: Ex Post Facto

Ex Post Facto Laws: (See Raines)

Is a law that applies retrospectively with a negative effect upon a person’s rigths by criminalizing a previous action or behavior.


  1. Statute/law Must be retrospective,


  1. It must disadvantage the party.

Ex. It turns prior innocent behavior into a crime, makes a crime greater than what it originally was, affects the laws of evidence

Analysis framework:

  1. Was the legislative intent punitive? If yes, inquiry ends = Impermissible Ex Post Facto law.
  2. If no, and th elaw was regulatory, civil, and nonpunitative = OK, not Ex Post Facto law

U.S. Sup CT. (Mendoza).

Mendoza Factors to consider:

  1. Can the new law be considered historical punishment?
  2. Does the law impose affirmative disability or restraint?
  3. Does the law promote traditional aims of punishment, retribution & deterrence?
  4. Whether an alternative purpose to which the law may rationally be connected is assignable for it,and
    1. Whether it appears excessive in relation to the alternative purpose assigned