The Fifth Amendment to the U.S. Constitution is part of the Bill of Rights and protects a person from being compelled to be a witness against himself in a criminal case. "Pleading the Fifth" is a colloquial term for invoking the privilege that allows a witness to decline to answer questions where the answers might incriminate him. A defendant cannot be compelled to become a witness at his own trial. The Amendment requires that felonies be tried only upon indictment by a grand jury. Federal grand juries can force people to take the witness stand, but defendants in those proceedings have Fifth Amendment privileges until they choose to answer any question. The Amendment's Double Jeopardy Clause provides the right to be tried only once in federal court for the same offense. Finally, the Amendment requires that the power of eminent domain be coupled with "just compensation" for those whose property is taken.

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