ex post facto
By retroactive application of a law formulated or enacted after the deed in questionBy retroactive application of a law formulated or enacted after the deed in question.
» You're allowed to make up rules, but you can't apply them ex post facto.
rul · Tatoeba · CC BY 2.0 FRMeaning
1 senses(not comparable)By retroactive application of a law formulated or enacted after the deed in question.
What he did was not a crime when he did it, but he was convicted ex post facto.
Examples
2 sentencesYou're allowed to make up rules, but you can't apply them ex post facto.
U.S. soldiers whose separation from service is delayed due to a stop loss stop movement policy, are compensated ex post facto.
Origin
From Latin ex (“from”) + post (“after”) + factō, ablative of factum (“deed”). In Latin, exFrom Latin ex (“from”) + post (“after”) + factō, ablative of factum (“deed”). In Latin, ex takes the ablative case, while post takes the accusative case. (See Wikipedia for a discussion of the grammatical form and usage of this phrase.)
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