What is the Fifth Amendment?
No person shall be held to answer for a capital, or otherwise infamous crime, unless on a presentment or indictment of a Grand Jury, except in cases arising in the land or naval forces, or in the Militia, when in actual service in time of War or public danger; nor shall any person be subject for the same offence to be twice put in jeopardy of life or limb; nor shall be compelled in any criminal case to be a witness against himself, nor be deprived of life, liberty, or property, without due process of law; nor shall private property be taken for public use, without just compensation.
The Fifth Amendment to the United States Constitution is part of the Bill of Rights and, among other things, protects individuals from being compelled to be witnesses against themselves in criminal cases.
“Pleading the Fifth” is a term for invoking the right that allows witnesses to decline to answer questions where the answers might incriminate them and/or without having to suffer a penalty for asserting that right.
This privilege ensures that defendants cannot be compelled to become witnesses at their own trials.
However, If they choose to testify, they are not entitled to the right during cross-examination, where questions are relevant to their testimony on direct examination.
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.
To claim the privilege for failure to answer when being interviewed by police, the interviewee must have explicitly invoked the constitutional right when declining to answer questions.