The idea that a person cannot be tried more than once for the same offence. The legal principle seems to have its basis in Roman law, and has found its way into the constitutions and statutes of many countries. For instance, Article 20(2) of India’s Constitution states: “No person shall be prosecuted and punished for the same offence more than once.” The Fifth Amendment of the Constitution of the United States, which relates to criminal and civil legal proceedings, contains a similar clause. Exceptions to the rule exist, for example, if the case against someone ends in a mistrial, then the defendant may be retried.
