accessory after the fact
Definition from Wiktionary, the free dictionary
- (law) A person who assists or protects someone wanted by the police in connection with a crime.
1749, Henry Fielding, chapter II, in The History of Tom Jones, a Foundling, London: A[ndrew] Millar, OCLC 928184292, book III:
- ...some of that atrocious wickedness in Jones, ... might perhaps be derived from the encouragement he had received from this fellow, who ... had been what the law calls an accessary after the fact...