Criminal Law 101: DOJ/US Attorney's Office Manual Explanation of Transactional and Use Immunity

2. Statutory Basis For Immunity

An immunized witness cannot refuse to testify on the ground that his testimony will incriminate him. Immunity is a useful investigative tool, particularly in antitrust conspiracy cases where there is usually little probative physical evidence and few, if any, uninvolved witnesses. All Division attorneys should have a working knowledge of the relevant law and internal Department and Division policies and procedures before seeking immunity for any witness.

Two broad categories of immunity have been used in the federal system: "transactional" immunity and "use" immunity. Transactional immunity precludes the Government from prosecuting a witness for any offense (or "transaction") related to the witness' compelled testimony. Use immunity precludes the Government from using, directly or indirectly, a witness' compelled testimony in a prosecution of that witness.

Before 1970, prosecutors of antitrust offenses (as well as most other federal crimes) relied on transactional immunity to compel self-incriminating testimony.⁽⁴³⁾ Transactional immunity was of only limited usefulness to prosecutors because it provided no incentive for witnesses to be fully cooperative. Once a witness testified about any matter relating to an offense, he achieved full protection from prosecution for that offense, and had little to gain from providing additional details about it. Recognizing that problem, in 1970, Congress repealed the pre-existing federal antitrust immunity statute and other transactional immunity statutes, and adopted a general use immunity statute for all federal crimes. The new statute, commonly called the Witness Immunity Act of 1970, was part of the Organized Crime Control Act of 1970. It is codified at 18 U.S.C. §§ 6001-05⁽⁴⁴⁾ and should be read by all Division attorneys staffing grand jury investigations.

The constitutionality of the new immunity statute was upheld in Kastigar v. United States, 406 U.S. 441 (1972). The Supreme Court held that the statute was compatible and coextensive with the 5th Amendment because it provided immunized witnesses with substantially all the protection accorded by the 5th Amendment privilege. A witness testifying under the statute cannot incriminate himself by his testimony because the statute absolutely proscribes any direct or indirect use of the witness' testimony against the witness. Hence, the prosecutor is left in precisely the same position vis-a-vis the witness as if the witness had not testified. The Court observed that transactional immunity provides considerably broader protection than the 5th Amendment, and thus was not constitutionally required. The Court emphasized, however, that if an immunized witness is later prosecuted, the Government has the affirmative duty of proving that the incriminating evidence it proposes to use is "derived from a legitimate source wholly independent of the compelled testimony."⁽⁴⁵⁾

The federal immunity statute is an attempt by Congress to accommodate two crucial yet competing interests: the Government's need to obtain testimony from culpable individuals to prosecute more culpable individuals, and the witness' right to refrain from incriminating himself. It grants the prosecutor a powerful tool for obtaining testimony, and imposes stringent limits on the use of such testimony.

3. Scope of Protection

18 U.S.C. §§ 6001-6005 is the only immunity statute used by the Division. Its constitutionality is settled beyond any doubt. Requests for transactional immunity should be opposed automatically.

Use immunity is much more useful to prosecutors than transactional immunity. As noted above, witnesses testifying with transactional immunity have little incentive to provide detailed incriminating testimony concerning offenses for which they have exposure.⁽⁴⁶⁾ Use immunity, however, gives the witness an incentive to be as forthcoming as possible because the witness is guaranteed only that the information he supplies cannot be used against him. For every new piece of information he supplies, it may become more difficult for a prosecutor to demonstrate that a future prosecution of the witness is based entirely on independent evidence. If this is properly explained to immunized witnesses, considerable detailed inculpatory testimony can often be elicited.⁽⁴⁷⁾

Use immunity is also useful to prosecutors because, unlike transactional immunity, it permits prosecution of immunized witnesses based on independent evidence. The Division is undertaking such prosecutions with increasing frequency. For example, where an immunized witness denies involvement in a conspiracy but is subsequently linked to the conspiracy by other evidence, the Division has prosecuted the witness both for the substantive offense and perjury.⁽⁴⁸⁾

The immunity statute specifically states that immunized testimony cannot 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." Clearly, a witness who testifies falsely under an immunity order can be prosecuted for perjury or other false statement offenses. The perjury is not compelled testimony about a past crime that is subject to 5th Amendment protection. Rather, the false testimony is itself the crime, and is not subject to any conceivable constitutional protection. However, if a witness testifies with immunity and confesses that he committed perjury on a previous occasion, his confession cannot be used to prosecute him for the previous testimony.

It should be noted that the immunity statute not only bars use of a witness' testimony as substantive evidence against that witness but also bars use of the immunized testimony to impeach the witness at trial.⁽⁴⁹⁾

The immunity statute only protects a witness from prosecution for offenses committed before the date of the witness' immunized testimony.⁽⁵⁰⁾ The witness' immunized testimony can always be used to prosecute him for crimes committed after the date of his testimony.

A grant of immunity before a federal grand jury will preclude use of that testimony in a state criminal prosecution just as a grant of state immunity will foreclose use by federal criminal prosecutors.⁽⁵¹⁾ The second prosecution may, however, go forward, provided the second prosecutor is able to establish that all of the evidence he had against the defendant was derived from sources independent of the earlier immunized testimony.⁽⁵²⁾ The best practice to follow when there is a state criminal grand jury investigation running simultaneously with the federal antitrust grand jury investigation is to erect a "Chinese wall" to ensure that Division attorneys are not foreclosed from prosecuting an individual immunized by the state by having access to any of the state's evidence.

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