Article I, Section 6, Clause 1:

The Senators and Representatives shall receive a Compensation for their Services, to be ascertained by Law, and paid out of the Treasury of the United States. They shall in all Cases, except Treason, Felony and Breach of the Peace, be privileged from Arrest during their Attendance at the Session of their respective Houses, and in going to and returning from the same; and for any Speech or Debate in either House, they shall not be questioned in any other Place.

The Supreme Court has described the Speech or Debate Clause as a provision that cannot be interpreted literally,1 but instead must be construed “broadly” in order to effectuate the Clause’s vital role in the constitutional separation of powers.2 “Deceptively simple” 3 phrases—such as “shall not be questioned,” “Speech or Debate,” and even “Senators and Representatives” —have therefore been accorded meanings that extend well beyond their literal constructions.4 Arguably, this purpose-driven interpretive approach has given rise to some ambiguity in the precise scope of the protections afforded by the Clause. Despite uncertainty at the margins, it is well established that the Clause serves to secure the independence of the federal legislature by providing Members of Congress and their aides with immunity from criminal prosecutions or civil suits that stem from acts taken within the legislative sphere.5 As succinctly described by the Court, the Clause’s immunity from liability applies “even though their conduct, if performed in other than legislative contexts, would in itself be unconstitutional or otherwise contrary to criminal or civil statutes.” 6 This general immunity principle forms the core of the protections afforded by the Clause.

Once it is determined that the Clause applies to a given action, the resulting protections from liability are “absolute,” 7 and the action “may not be made the basis for a civil or criminal judgment against a Member.” 8 In such a situation, the Clause acts as a jurisdictional bar to the legal claim.9 But this immunity is also complemented by two component privileges (an evidentiary privilege and a testimonial privilege) that emanate from the Clause and can be asserted to prevent certain compelled disclosures. Even if absolute immunity is inappropriate, the evidentiary component of the Clause prohibits the introduction of evidence of legislative acts for use against a Member,10 while the testimonial privilege protects Members from compelled testimony on protected acts.11 The Supreme Court has not explicitly framed the protections of the Clause by reference to these two independent component privileges, but has instead implicitly recognized their existence.12 As a result, these privileges are neither clearly established nor described, and may further contribute to the unsettled aspects of the Clause.

Footnotes

1

Hutchinson v. Proxmire, 443 U.S. 111, 124 (1979) (noting that the “Court has given the Clause a practical, rather than a strictly literal, reading . . .” ).

2

Eastland v. U.S. Servicemen’s Fund, 421 U.S. 491, 501 (1975) ( “Without exception, our cases have read the Speech or Debate Clause broadly to effectuate its purposes.” ).

3

Brown & Williamson Tobacco Corp. v. Williams, 62 F.3d 408, 415 (D.C. Cir. 1995).

4

Kilbourn v. Thompson, 103 U.S. 168, 204 (1881).

5

Eastland, 421 U.S. at 510–11 (noting that the Clause should be “construed to provide the independence which is its central purpose” ); United States v. Johnson, 383 U.S. 169, 182 (1966) ( “There is little doubt that the instigation of criminal charges against critical or disfavored legislators by the executive in a judicial forum was the chief fear prompting the long struggle for parliamentary privilege in England and, in the context of the American system of separation of powers, is the predominate thrust of the Speech or Debate Clause.” ).

6

Doe v. McMillan, 412 U.S. 306, 312–13 (1973).

7

Eastland, 421 U.S. at 503 ( “[O]nce it is determined that Members are acting within the ‘legitimate legislative sphere’ the Speech or Debate Clause is an absolute bar to interference.” ); McMillan, 412 U.S. at 324 ( “The business of Congress is to legislate; Congressmen and aides are absolutely immune when they are legislating.” ).The Court has gone so far as to say that legislative acts may not even be the subject of “inquiry” by either the executive or Judicial Branches. United States v. Brewster, 408 U.S. 501, 509 (1972) ( “The privilege protect[s] Members from inquiry into legislative acts or the motivation for actual performance of legislative acts.” ).

8

McMillan, 412 U.S. at 312.

9

See McMillan, 412 U.S. at 318; see also Fields v. Off. of Johnson, 459 F.3d 1, 13 (D.C. Cir. 2006) (quoting McMillan and explaining that “[t]he Speech or Debate Clause operates as a jurisdictional bar when ‘the actions upon which [a party seeks] to predicate liability [are] ‘legislative acts.’” ).

10

United States v. Helstoski, 442 U.S. 477, 487 (1979) (noting that the Court’s previous holdings “leave no doubt that evidence of a legislative act of a Member may not be introduced by the Government” ); Brewster, 408 U.S. at 527 (holding that “evidence of acts protected by the Clause is inadmissible” ).

11

Gravel v. United States, 408 U.S. 606, 616 (1972) ( “We have no doubt that Senator Gravel may not be made to answer—either in terms of questions or in terms of defending himself from prosecution—for the events that occurred at the subcommittee meeting.” ).

12

Indeed, the Supreme Court has never used the phrase “testimonial privilege” or “evidentiary privilege” in discussing the Speech or Debate Clause. In United States v. Gillock, the Court referenced an evidentiary privilege for state legislators “similar in scope” to the Clause. 445 U.S. 360, 366 (1980).