“…nor shall [any person] be compelled in any criminal case to be a witness against himself…”
Probably most Americans already have a basic understanding of what it means for a person to “take the Fifth”—at least those Americans who watch Law & Order. In general, it means that no criminal defendant can be forced to answer the police’s questions or take the witness stand at his own trial. It also means that witnesses cannot be forced to give testimony that would have the effect of incriminating them.
While the prohibition on compulsory self-incrimination was a well established principle long before the American Founding, it is not entirely certain what the original reasons for the principle might have been.
Many people at the time the 5th Amendment was adopted argued that it was a protection against ancient abuses of the courts; in particular, it was meant to prevent the once widespread practice of extracting evidence on pain of torture. Joseph Story, in his 1833 Commentaries on the Constitution, defended its inclusion in the Bill of Rights because “it is well known, that in some countries, not only are criminals compelled to give evidence against themselves, but are subjected to the rack or torture in order to procure a confession of guilt.”
There was probably more to the reasoning behind the ban on self-incrimination, however, than simply preventing confessions extracted from torture. As one judge in an 1802 case (Respubilca v. Gibbs) put it: “It is considered cruel and unjust to propose questions which may tend to criminate the party.” Such questioning, if it were compulsory, would leave the guilty party with only two choices, both of which would be extremely undesirable. Either he can tell the truth (which might lead to civil punishments) or he can swear falsely (which might lead to everlasting perdition). A humane government, it was thought, would not place any person, even one who was guilty, on the horns of that dilemma.
Moreover, as a practical matter, any person who was guilty of a crime and forced to testify about his own conduct would have a tremendous temptation to lie about it. Thus such testimony should be deemed untrustworthy. Therefore, if any confessions are forthcoming, they must be given freely, and the state must rely on other means of discovering who committed a crime.
Several early state constitutions had protections against self-incrimination, and several states recommended that the clause be added to the United States Constitution. Madison’s original proposal for the self-incrimination clause did not specify that it was to apply only to criminal cases, and the House changed the wording to make that clear. Once amended, the clause passed unanimously in the House and without further debate.