Federal Immunity Agreements Use Immunity Vs Transactional Immunity

The Fifth Amendment guarantees that no person "shall be compelled in any criminal case to be a witness against himself." When the government needs testimony from a witness who invokes that privilege, federal prosecutors must choose between two forms of immunity: use immunity and transactional immunity. The distinction is not academic. It determines whether the witness can ever be prosecuted for the underlying conduct, and it shapes every strategic decision from the moment a subpoena arrives.

Federal law resolves the choice decisively. Under 18 U.S.C. § 6002, a witness may be compelled to testify after a court order grants immunity, but that immunity is use immunity only. Transactional immunity, by contrast, is a broader protection that federal courts do not require and prosecutors seldom offer. Understanding the difference is essential for anyone facing a federal grand jury or compelled testimony.

The Statutory Architecture of 18 U.S.C. § 6002 and the Limits of Compelled Testimony

Congress enacted the modern federal immunity statute in 1970 as part of the Organized Crime Control Act. Section 6002 provides that when a witness is ordered to testify over a claim of privilege, "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." That language defines use immunity.

The statute also requires the government to follow a specific procedural path. A United States Attorney must request the order from a district court, and the court must inform the witness that the order compels testimony. See 18 U.S.C. § 6003. Once the order issues, the witness has no lawful basis to refuse. The privilege against self-incrimination is displaced by the immunity grant.

The Supreme Court upheld this framework in Kastigar v. United States, 406 U.S. 441 (1972). The Court held that use immunity is coextensive with the Fifth Amendment privilege and that transactional immunity is not constitutionally required. Kastigar remains the controlling authority on federal immunity.

The practical consequence is significant. A witness who receives use immunity can still be prosecuted for the same conduct, provided the government proves that its evidence comes from a legitimate source independent of the compelled testimony. This is the "independent source" doctrine. The government bears the burden of establishing that its case is not tainted by the immunized testimony.

"The privilege against self-incrimination is not a prohibition on prosecution; it is a prohibition on compelled self-incrimination. Use immunity satisfies the Constitution by removing the compelled element." — Kastigar v. United States, 406 U.S. 441, 462 (1972) (paraphrased).

Defense counsel must therefore scrutinize the government's evidence trail. If the prosecution's case relies on witnesses, documents, or investigative leads that were developed after the immunized testimony, the defense can move to suppress under Kastigar. The motion practice is fact-intensive and often requires a Kastigar hearing.

Prosecutors sometimes attempt to build a "clean team" — a separate group of investigators and attorneys who are walled off from the immunized testimony. If the wall is breached, the prosecution may be disqualified. Courts have granted such relief in cases where the taint was pervasive.

Use immunity also extends to the fruits of the testimony. The statute expressly covers "any information directly or indirectly derived" from the compelled statements. That includes derivative evidence, such as a bank record discovered because of a witness's description of a transaction. The government cannot use that record in a subsequent case against the witness.

However, the government may use the immunized testimony for other purposes. It can prosecute the witness for perjury or false statements made during the immunized testimony itself. See 18 U.S.C. § 6002 (the immunity does not apply to a prosecution for perjury or contempt). It can also use the testimony in a case against a third party. The immunity is personal to the witness.

These limits mean that use immunity is not a blanket shield. A witness who testifies falsely under a § 6002 order faces new charges. A witness who provides information that leads to evidence against another person cannot claim that the evidence is inadmissible in the other person's trial.

Transactional Immunity: Broader Protection, Rare in Federal Court

Transactional immunity is the older and broader form. It bars prosecution for the transaction or offense to which the compelled testimony relates. If a witness receives transactional immunity and testifies about a drug conspiracy, the government cannot later charge that witness with participating in that conspiracy. The immunity attaches to the conduct, not merely to the use of the testimony.

Many states once required transactional immunity as a matter of state constitutional law. The federal government, however, has never adopted it as a statutory default. Section 6002 grants only use immunity. A federal prosecutor may offer transactional immunity as part of a plea agreement or cooperation deal, but the government is not obligated to do so.

The distinction matters most when the government wants to prosecute the witness for the same conduct. With use immunity, the prosecution can proceed if it has independent evidence. With transactional immunity, the prosecution is barred outright. That is why defense counsel often seeks transactional immunity in negotiations, while prosecutors resist it.

Federal courts have consistently held that transactional immunity is not required by the Fifth Amendment. The Supreme Court in Kastigar rejected the argument that only transactional immunity can adequately protect the privilege. The Court reasoned that use immunity, combined with the government's burden to prove an independent source, is sufficient.

Some federal statutes provide transactional immunity in specific contexts. For example, the federal witness immunity statute for certain antitrust matters, 15 U.S.C. § 1312, and the immunity provisions in the Organized Crime Control Act, 18 U.S.C. § 6002, are use immunity provisions. Transactional immunity appears more often in state statutes or in negotiated agreements.

A defendant who receives transactional immunity in a federal case typically does so through a cooperation agreement. The agreement may provide that the government will not prosecute the defendant for specified offenses in exchange for testimony. That is a contractual immunity, not a statutory one. Breach of the agreement by the defendant can void the protection.

Defense counsel must carefully review any immunity agreement for its scope. Does it cover only the offenses described in the agreement? Does it cover related conduct? Does it require the defendant to testify truthfully? What happens if the government later decides the defendant breached the agreement? These questions determine the real value of the immunity.

• Use immunity — bars use of compelled testimony and its fruits; prosecution possible with independent evidence.
• Transactional immunity — bars prosecution for the transaction or offense entirely; broader but not constitutionally required.
• Derivative use immunity — a subset of use immunity; bars use of evidence derived from compelled testimony.
• Negotiated immunity — contractual protection in a plea or cooperation agreement; scope depends on the agreement's terms.

The practical reality is that most federal witnesses receive use immunity under § 6002. Transactional immunity is reserved for high-value cooperators or specific statutory contexts. A witness who refuses to testify after a § 6002 order faces contempt, which can be civil or criminal. See 28 U.S.C. § 1826 (civil contempt for recalcitrant witnesses) and 18 U.S.C. § 401 (criminal contempt).

Contempt can be coercive. A witness can be incarcerated until he or she complies with the order. The Supreme Court has upheld indefinite civil contempt in this context, provided the witness has the keys to his or her own cell. See Shillitani v. United States, 384 U.S. 364 (1966).

For a defendant facing a grand jury subpoena, the choice is stark. Testify under use immunity and risk prosecution if the government finds independent evidence. Refuse and face contempt. The only way to obtain transactional immunity is to negotiate it, and the government has little incentive to offer it.

FAQ

Q: Can the government prosecute a witness who testified under use immunity?
A: Yes. Use immunity does not bar prosecution. The government may prosecute if it can prove that its evidence comes from a source independent of the compelled testimony. The burden is on the prosecution to establish an independent source, and the defense can challenge the evidence through a Kastigar hearing.

Q: Is transactional immunity ever available in federal court?
A: It is available only if the government chooses to grant it, typically through a cooperation or plea agreement. Federal law does not require transactional immunity, and courts will not impose it. A witness who wants transactional immunity must negotiate for it, and the government may refuse.

Any person who receives a federal subpoena or is asked to testify under an immunity order should consult counsel immediately. The difference between use immunity and transactional immunity can determine whether a witness walks away free or faces indictment. Federal criminal defense counsel can evaluate the scope of any immunity grant, negotiate for broader protection where possible, and litigate Kastigar motions if the government attempts to use tainted evidence. The stakes are too high to proceed without a clear understanding of the law.