18 U.S.C. § 6002 : US Code - Section 6002: Immunity generally

Search 18 U.S.C. § 6002 : US Code - Section 6002: Immunity generally

Whenever a witness refuses, on the basis of his privilege against
self-incrimination, to testify or provide other information in a
proceeding before or ancillary to -
(1) a court or grand jury of the United States,
(2) an agency of the United States, or
(3) either House of Congress, a joint committee of the two
Houses, or a committee or a subcommittee of either House,
and the person presiding over the proceeding communicates to the
witness an order issued under this title, the witness may not
refuse to comply with the order on the basis of his privilege
against self-incrimination; but no testimony or other information
compelled under the order (or any information directly or
indirectly derived from such testimony or other information) may be
used against the witness in any criminal case, except a prosecution
for perjury, giving a false statement, or otherwise failing to
comply with the order.