770
Opinion of Thomas, J.
rivative use immunity mandated by Kastigar when the government compels testimony from a reluctant witness. See 406 U. S., at 453. Accordingly, the fact that Martinez did not know his statements could not be used against him does not change our view that no violation of the Fifth Amend-ment's Self-Incrimination Clause occurred here.
3
Although our cases have permitted the Fifth Amendment's self-incrimination privilege to be asserted in noncriminal cases, see id., at 444-445 (recognizing that the "Fifth Amendment privilege against compulsory self-incrimination . . . can be asserted in any proceeding, civil or criminal, administrative or judicial, investigatory or adjudicatory . . ."); Lefkowitz v. Turley, supra, at 77 (stating that the Fifth Amendment privilege allows one "not to answer official questions put to him in any other proceeding, civil or criminal, formal or informal, where the answers might incriminate him in future criminal proceedings"), that does not alter our conclusion that a violation of the constitutional right against self-incrimination occurs only if one has been compelled to be a witness against himself in a criminal case.
In the Fifth Amendment context, we have created prophylactic rules designed to safeguard the core constitutional right protected by the Self-Incrimination Clause. See, e. g., Tucker, 417 U. S., at 444 (describing the "procedural safeguards" required by Miranda as "not themselves rights protected by the Constitution but . . . measures to insure that the right against compulsory self-incrimination was protected" to "provide practical reinforcement for the right"); Elstad, supra, at 306 (stating that "[t]he Miranda exclusionary rule . . . serves the Fifth Amendment and sweeps more broadly than the Fifth Amendment itself"). Among these rules is an evidentiary privilege that protects witnesses from being forced to give incriminating testimony, even in non-criminal cases, unless that testimony has been immunized
Page: Index Previous 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 NextLast modified: October 4, 2007