Double Jeopardy Clause

The Double Jeopardy Clause of the Fifth Amendment to the United States Constitution provides: "[N]or shall any person be subject for the same offence to be twice put in jeopardy of life or limb..." The four essential protections included are prohibitions against, for the same offense: retrial after an acquittal; retrial after a conviction; retrial after certain mistrials; and multiple punishment Jeopardy attaches in jury trial when the jury is empaneled and sworn in, in a bench trial when the court begins to hear evidence after the first witness is sworn in, or when a court accepts a defendant's plea unconditionally. Jeopardy does not attach in a retrial of a conviction that was reversed on appeal on procedural grounds (as opposed to evidentiary insufficiency grounds), in a retrial for which "manifest necessity" has been shown following a mistrial, and in the seating of another grand jury if the prior one refuses to return an indictment.