Federal Immunity Agreements: Use Immunity vs. Transactional Immunity

Key Takeaways

Federal use immunity under 18 U.S.C. § 6002 bars the direct and derivative use of compelled testimony in a later criminal case, but not a prosecution built on independent evidence.
Transactional immunity — a complete bar to prosecution for the transaction testified about — is no longer part of the federal compulsory process; it survives mainly in certain state statutes and in contractual non-prosecution agreements.
After an immunity grant, the government must show in a Kastigar hearing that any evidence it uses came from a source wholly independent of the compelled testimony.
An immunity order under 18 U.S.C. § 6003 requires approval at the level of the Attorney General, the Deputy Attorney General, or a designated Assistant Attorney General, and a finding that the testimony is necessary to the public interest.

The immunity statute

18 U.S.C. § 6002 provides the operative protection. When a witness refuses to testify on the basis of the privilege against self-incrimination in a proceeding before a court, grand jury, agency, or House of Congress, and the person presiding over the proceeding communicates an order issued under the title, the witness may not refuse to comply on the basis of the privilege. But no testimony or other information compelled under the order — or any information directly or indirectly derived from it — 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.

How an order is obtained

The procedural mechanism is 18 U.S.C. § 6003. The United States Attorney applies to the district court for an order compelling testimony, after approval from the Attorney General, the Deputy Attorney General, or a designated Assistant Attorney General. The application must certify that the testimony may be necessary to the public interest and that the witness has refused, or is likely to refuse, to testify on the basis of the privilege against self-incrimination. Once the court issues the order, the witness must testify or face contempt sanctions.

Kastigar and the Fifth Amendment

In Kastigar v. United States, 406 U.S. 441 (1972), the Supreme Court held that use and derivative use immunity satisfies the Fifth Amendment because the protection is coextensive with the privilege: the witness is left in substantially the same position as if the privilege had been asserted. The decision also made clear that transactional immunity is not constitutionally required. If the government later prosecutes a witness who received immunity, it bears the burden at a Kastigar hearing of showing that its evidence came from a legitimate source wholly independent of the compelled testimony.

Use immunity vs. transactional immunity

Use immunity protects against the use of the compelled testimony and its fruits. Transactional immunity would bar any prosecution for the transaction about which the witness testified, regardless of the source of the government's evidence. The federal compulsory process has used the use-immunity model since the Organized Crime Control Act of 1970. Transactional immunity remains available in some state systems — for example, under California Penal Code § 1324 — and federal prosecutors may also agree contractually, in a plea or cooperation agreement, not to prosecute disclosed conduct.

Published by the Corydon Law Research Desk — John D. Kirby, publisher — former federal prosecutor. This page is reference information about federal law and procedure, not legal advice.

Primary sources

18 U.S.C. § 6002 — text of the statute or rule as published by law.cornell.edu (law.cornell.edu). Verbatim: “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.”
Kastigar v. United States, 406 U.S. 441 (1972) — opinion and full text (courtlistener.com). The decision holds that use and derivative use immunity is coextensive with the Fifth Amendment privilege.

Sources listed above were accessed and verified on August 20, 2026. Statutes and rules are quoted from the linked primary pages as published on that date. Information on this site is general in nature and is not legal advice.