I. |ekˌspōst|fak(ˌ)tō adjective
Etymology: Late Latin, from a thing done afterward
: done, made, or formulated after the fact and on the basis of current premises, conditions, or knowledge : disregarding the previous status or setting of the event or thing concerning which a conclusion is reached or at which action is directed : retrospective , retroactive
ex post facto punishment
the general gave his ex post facto approval — W.H.Upson
ex post facto rationalizations of behavior — Edward Sapir
the results of scientific inquiry are always subject to ex post facto interpretation — H.M.Magid
II. adverb
: after the fact : in a retrospective or retroactive manner
no lawmaker can alter the fact, ex post facto — C.A.Beard