Trammel v. United States, 445 U.S. 40 (1980) (U.S. Supreme Court)
Trammel v. United States marks a pivotal recalibration of the common-law spousal privileges in federal courts.
Under the federal common law of privileges, as informed by Federal Rule of Evidence 501, who holds the adverse spousal testimonial privilege—the accused spouse or the witness-spouse—and may an accused bar a willing spouse from testifying adversely at trial?
Under Federal Rule of Evidence 501, privileges in federal criminal cases are governed by the common law as interpreted by the courts of the United States in light of reason and experience. The adverse spousal testimonial privilege belongs to the witness-spouse alone; a witness-spouse may choose to refuse to testify adversely against the defendant spouse, but the defendant spouse has no right to prevent the witness-spouse from testifying voluntarily. This ruling does not alter the separate marital communications privilege, which protects confidential communications made between spouses during a valid marriage and may be asserted by either spouse.
The Supreme Court held that the adverse spousal testimonial privilege is vested solely in the witness-spouse. Accordingly, a defendant cannot bar a willing spouse from testifying against him. The Court affirmed Trammel's conviction.
Trammel is foundational for understanding the two distinct marital privileges and their operation in federal court. It (1) reassigns control of the adverse spousal testimonial privilege to the witness-spouse, preventing defendants from silencing a willing spouse; (2) preserves the marital communications privilege for confidential spousal communications; and (3) models how Rule 501 enables courts to modernize privilege doctrine in light of contemporary values and practical prosecutorial needs. The decision is frequently tested in Evidence courses and on bar exams to assess students' ability to differentiate the privileges, identify who may invoke them, and determine their temporal scope.