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 Congress members from lawsuits over 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 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, used with permission from the Associated Press)
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.
U.S. Senator Robert “Bob” Menendez from New Jersey recently 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.
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.