In civil and military jurisprudence, summary execution is the putting to death of a person accused of a crime without the benefit of a free and fair trial. The term results from the legal concept of summary justice to punish a summary offense, as in the case of a drumhead court-martial, but the term usually denotes the summary execution of a sentence of death. Under international law, it is a combatant's refusal to accept an opponent's lawful surrender and the combatant's provision of no quarter, by killing the surrendering opponents.
Summary executions have been practiced by police, military, and paramilitary organizations and are frequently associated with guerrilla warfare, counter-insurgency, terrorism, and any other situation which involves a breakdown of the normal procedures for handling accused prisoners, civilian or military.