a law that changes the consequences of actions that occurred before the law existed, for example making illegal an action that was legal at the time it was committed
Synonyms and related words
The law, laws and parts of laws
act
adjective law
the administration of justice
Synonyms and related words
Foreign legal terms
ab initio
actus reus
a fortiori
ex post facto law
noun countable legal
US /ˌeks poʊst ˈfæktoʊ ˌlɔ/
Word Forms
singular
ex post facto law
plural
ex post facto laws
DEFINITIONS1
1
a law that changes the consequences of actions that occurred before the law existed, for example making illegal an action that was legal at the time it was committed