ex post facto

American  

[eks pohst fak-toh] / ˈɛks ˌpoʊst ˈfæk toʊ /

adverb

1. from or by subsequent action; retroactively; subsequently; retrospectively.

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adjective

1. having retroactive force; made or done subsequently.

   an ex post facto law.

ex post facto British  

/ ɛks pəʊst ˈfæktəʊ /

adjective

1. having retrospective effect

   an ex post facto law

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ex post facto ¹ Cultural  

1. An explanation or regulation concocted after the event, sometimes misleading or unjust: “Your ex post facto defense won't stand up in court.” (See ex post facto law.) From Latin, meaning “after the deed.”

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ex post facto ² Cultural  

1. A descriptive term for an explanation or a law that is made up after an event and then applied to it: “The chairman's description of his plan sounds like an ex post facto attempt to justify an impulsive action.” Ex post facto is Latin for “from after the deed.”

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Etymology

Origin of ex post facto

First recorded in 1625–35; from Latin: “from a thing done afterward, from what is done afterward”

Example Sentences

“This is a violation of the ex post facto clause of the constitution,” said Neama Rahmani, president of West Coast Trial Lawyers.

From Washington Times • Feb. 10, 2023

As for the claim of ex post facto justice, Robert Jackson — the American prosecutor who believed aggression enabled all the other war crimes that followed — summed up the charge:

From Salon • Jan. 7, 2023

The ban on ex post facto laws, the court said, prohibits increasing the punishment for a crime after the crime was committed, and that it does not apply in the inmates’ cases.

From Seattle Times • Nov. 13, 2021

Joe Grogan, former head of the Domestic Policy Council, said that the analyses now, more than half a year later, are “all ex post facto about where this was going to go.”

From Washington Post • Sep. 16, 2020

There is reason to believe that recollection was an ex post facto elaboration; those on the scene recall a sensation more suggestive of relief and euphoria in the air.

From "Big Science" by Michael Hiltzik