Brown v. Walker
Citation and Court
161 U.S. 591 (1896), Supreme Court of the United States
Facts
Walker was called before a grand jury investigating illegal railroad rebating. Congress had passed an immunity statute granting witnesses compelled to testify before the ICC full immunity from prosecution. Walker refused to answer, arguing the statute was insufficient to displace his Fifth Amendment privilege.
Issue
Whether Congress may compel testimony by granting immunity that is coextensive with the Fifth Amendment privilege, and whether such a statute eliminates the basis for invoking the privilege.
Holding
Congress may grant immunity from prosecution broad enough to displace the Fifth Amendment privilege, and a witness so immunized must testify; the immunity need not be a formal pardon but must be as broad as the privilege itself.
Rule / Doctrine
Statutory immunity displaces the Fifth Amendment privilege when it is coextensive with the privilege — that is, when it provides full protection against the use of the compelled testimony and its fruits in any subsequent criminal prosecution. A witness cannot refuse to testify on self-incrimination grounds after receiving immunity coextensive with the privilege. This “use and derivative use” or “transactional immunity” framework was later refined in Kastigar v. United States (1972).
Significance
Brown v. Walker is the foundational immunity case, establishing that Congress has the constitutional power to compel testimony by granting immunity coextensive with the Fifth Amendment privilege. It laid the doctrinal groundwork for the modern immunity statutes and the Supreme Court’s later decision in Kastigar, which held that use-and-derivative-use immunity (rather than full transactional immunity) satisfies the Fifth Amendment.