George W. Truett

The speech and debate clause of the Constitution protects Congress members from lawsuits for what they say during legislative activity. The Supreme Court held that the remarks of U.S. Sen. William Proxmire (pictured here) in a newsletter criticizing a behavioral scientist's work as a waste of taxpayer dollars was not protected under the speech and debate clause. (AP Photo/Henry Griffin)

The speech and debate clause, which appears in Article 1, section 6, of the U.S. Constitution, was written before the First Amendment and has a more limited scope.

The clause, whose inclusion reflected the development in England of an independent Parliament, states that “for any Speech or Debate in either House, they [members] shall not be questioned in any other Place.” It follows a provision, now largely moot, that prevents the arrest, for civil cases, of members traveling to or from sessions of Congress.

Speech and debate clause protects legislative speech

The general purpose of the speech and debate clause is to protect members of Congress from having to worry that anything they say in the course of legislative activities will implicate them in a lawsuit.

In United States v. Brewster, 408 U.S. 502 (1972), the Court distinguished between “purely legislative activities,” which the Speech and Debate Clause protected, and merely political activities, which it did not. In Gravel v. United States (1972), the Supreme Court extended the speech and debate clause to protect congressional aides, described as “alter egos,” for work in connection with such speeches, but limited the privilege to “legislative activity.”

It refused to extend the privilege to the subsequent publication of materials read in congressional debates — in this case the Pentagon Papers.

U.S. Sen. Bob Menendez in 2017 argued the speech and debate clause shielded him from prosecution on bribery and fraud charges related to gifts and campaign donations he accepted. But the lower courts did not agree with his arguments and the Supreme Court declined to review the case. (AP Photo/Julio Cortez)

Supreme Court allowed defamation suit against senator for newsletter comments

In Hutchinson v. Proxmire (1979), the Court permitted a defamation suit against a senator for derogatory comments made in a newsletter and in forums other than the Senate floor.

In Office of Senator Dayton v. Hanson (2007), the Court ruled that lower courts did not have jurisdiction in a claim against a U.S. senator’s office by a former employee. The senator’s office had sought immunity under the speech and debate clause. 

Menendez got evidence excluded in trial based on speech and debate clause

U.S. Senator Bob Menendez from New Jersey in 2017 sought to use the speech and debate clause to shield himself from allegations of bribery and public corruption.  However, lower courts have ruled that his lobbying activities on behalf of particular clients are not protected, and the Supreme Court decided not to review the case.

In Menendez's 2024 trial,  the judge, however, on the basis of the Speech and Debate Clause, excluded some evidence that the prosecution thinks is critical. The judge did so in party by relying on a ruling in a previous case, United States v. Helstoski, 442 U.S. 477 (1979), against allowing certain evidence against Rep. Henry Helstoski, who had also been accused of bribery.  Menendez was, however, convicted in 2024 and sentenced to 11 years in jail in 2025.

On House floor, Nancy Mace accuses four men of sexual exploitation 

On Feb. 10, 2025, Representative Nancy Mace, a Republican from South Carolina who had in recent years made other accusations of sexual assaults, delivered an unprecedented speech on the floor of the House of Representatives alleging that four men, including a former fiancé, had drugged and raped her and other women and taken pictures of them in the nude without their consent. Her speech of about an hour indicated that the men had booked themselves “a one-way ticket to hell” (Karni 2025). Her fiancé denied her accusation, for which she did not provide evidence in her speech. The South Carolina Attorney General, whom Mace accused of treating female victims as criminals, likewise denied having been informed of any such charges.

John Vile is a professor of political science and dean of the Honors College at Middle Tennessee State University. He is co-editor of the Encyclopedia of the First Amendment. This article was originally published in 2009.

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