## Facts

- The U.S. House of Representatives created a special committee to investigate a private “real-estate pool” in which the bankrupt firm Jay Cooke & Co. had an interest and was alleged to owe the United States.
- The committee subpoenaed Hallett Kilbourn, a private citizen involved in the partnership, to testify and to produce books and papers about the partnership’s business.
- Kilbourn appeared but refused to answer questions or produce the requested documents.
- The House adopted resolutions declaring Kilbourn in contempt and directing the Speaker to issue a warrant for his arrest.
- The House’s Sergeant-at-Arms, John G. Thompson, executed the warrant and confined Kilbourn in the District of Columbia jail for about 45 days.
- Kilbourn sued Thompson and certain House members for damages for false imprisonment, claiming the House lacked constitutional authority to compel testimony and punish contempt in this inquiry.
- The trial court upheld defendants’ immunity-based pleas and entered judgment for defendants; Kilbourn sought Supreme Court review.

## Issues

1. Whether either House of Congress may punish a private citizen for contempt for refusing to testify or produce documents when the inquiry concerns private affairs and is not within Congress’s legitimate legislative functions.
2. Whether House members and the Sergeant-at-Arms are immune from civil liability for false imprisonment for actions taken pursuant to House resolutions and a Speaker’s warrant.

## Decision

- The Court held the House lacked constitutional authority to imprison Kilbourn for contempt arising from this investigation because the inquiry exceeded the House’s legislative jurisdiction.
- The Court affirmed judgment for the House-member defendants, concluding the Speech or Debate Clause barred civil liability for their legislative acts (e.g., committee work, debate, and voting).
- The Court reversed judgment for Thompson and remanded, holding the Sergeant-at-Arms could not claim absolute legislative immunity for executing a warrant based on an unconstitutional exercise of House power.

## Legal Principles

- Congress has no general, inherent power to punish private citizens for contempt; any contempt power must be tied to powers expressly granted or necessary and proper to execute legitimate constitutional functions.
- Congressional investigations must relate to matters on which Congress may legislate; an inquiry that is essentially judicial in nature and directed at private affairs cannot support compulsory process and contempt imprisonment.
- The Speech or Debate Clause provides absolute immunity to members of Congress for acts within the legislative sphere, including committee proceedings and voting on resolutions.
- Legislative officers who execute arrest or imprisonment orders are not protected by the Speech or Debate Clause in the same manner as members and may be liable when enforcing an order issued without constitutional authority.

## Conclusion

The Court limited congressional investigatory and contempt authority to matters connected to legitimate legislative functions, invalidated the House’s imprisonment of a private citizen for refusing to cooperate in a nonlegislative inquiry, and drew a sharp immunity line between protected legislative acts of members and potentially actionable enforcement by the Sergeant-at-Arms.


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