Double jeopardy is a legal principle that prohibits an individual from being tried twice for the same offense following an acquittal or conviction. In the United States, this protection is guaranteed by the Fifth Amendment of the Constitution, which states that no person shall be subject for the same offense to be twice put in jeopardy of life or limb. This means that once a defendant has been acquitted or convicted of a particular crime, they cannot be retried in the same jurisdiction for that same offense. However, there are exceptions to this rule, such as when new evidence emerges or if the case is tried in a different jurisdiction. Double jeopardy protections ensure that individuals are not subjected to repeated prosecutions by the government, thus safeguarding their rights and promoting fairness in the criminal justice system. It is a fundamental aspect of the legal system that protects individuals from being unfairly targeted or harassed by the state.