1

ex post facto

adverb ex post fac·to \ ˌeks-ˌpōs(t)-ˈfak-(ˌ)tō \
Updated on: 10 Nov 2017

Definition of ex post facto

: after the fact : retroactively

Did You Know?

Ex post facto is Latin for "from a thing done afterward". Approval for a project that's given ex post facto—after the project already has been begun or completed—may just have been given in order to save face. An ex post facto law is one that declares someone's action to be criminal only after it was committed--a procedure forbidden by our Constitution.

Origin and Etymology of ex post facto

Late Latin, literally, from a thing done afterward


2

ex post facto

adjective

Definition of ex post facto

: done, made, or formulated after the fact : retroactive
  • ex post facto approval
  • ex post facto laws

Recent Examples of ex post facto from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ex post facto.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ex post facto

1787


Law Dictionary

1

ex post facto

adverb \ ˈeks-ˌpōst-ˈfak-tō \

legal Definition of ex post facto

: after the fact : retroactively
  • cannot judge ex post facto

Origin and Etymology of ex post facto

Late Latin, literally, from a thing done afterward


2

ex post facto

adjective

legal Definition of ex post facto

1 : done, made, or formulated after the fact : retroactive
2 : of or relating to an ex post facto law
  • the chief concerns of the ex post facto ban
  • —L. H. Tribe

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