Woodrow Wilson wrote in 1885 that Congress in session is Congress on public exhibition, while Congress in its committee rooms is Congress at work. The early Congresses referred each bill to a temporary select committee and disbanded it afterward. As the workload grew, the House and Senate created permanent standing committees with fixed jurisdictions, beginning with Ways and Means in 1802 and a batch of Senate committees in 1816. The Legislative Reorganization Act of 1946 consolidated dozens of overlapping committees into the basic structure that survives.
In the 119th Congress the House has twenty standing committees and the Senate sixteen, divided into roughly 200 subcommittees between them, plus joint committees shared by both chambers and select committees created for particular purposes such as intelligence. Each committee's jurisdiction is set by the chamber's rules, and bills are referred to the committee whose subject they touch. Of the thousands of bills introduced in each Congress, most are referred to committee and never acted on again. Committees decide which bills get hearings, rewrite them in markup sessions, and report the survivors to the floor.
Seats on committees are divided between the parties roughly in proportion to their strength in the chamber, with the majority holding a larger share and every chair. Each party's conference or caucus assigns its own members, and the most powerful committees, Appropriations, Ways and Means, Rules, Finance, and Judiciary among them, are prized assignments. Chairs control the agenda, hire most of the staff, and decide which bills move. For much of the twentieth century they were chosen strictly by seniority, a system that let long-serving Southern Democrats block civil rights legislation for decades. Reforms in the 1970s made chairs answer to the party caucus, and House Republicans have limited chairs to three terms since 1995.
Committees are also Congress's main instrument of oversight. They hold hearings, issue subpoenas, demand documents, and question officials, and some of the most consequential moments in American politics, from the Army-McCarthy hearings to Watergate to the January 6 committee, happened in committee rooms. Critics argue that power has drained from committees toward party leaders, who increasingly write major bills themselves and bring them to the floor without hearings or markup. Defenders of the change say it reflects how polarized the chambers have become.
| Status | Active |
| Part of | The United States Congress |
| Legal basis | U.S. Constitution, Article I, Section 5 (each chamber sets its rules), Legislative Reorganization Acts of 1946 and 1970 |
| Official site | congress.gov |
| Standing committees | 20 in the House, 16 in the Senate (119th Congress) |
| Subcommittees | Roughly 200 combined |
| Types | Standing, select, joint, conference |
| Chairs | Majority party, selected by party caucus |
| Chair term limit | Three terms for House Republicans since 1995 |
| First standing committee | House Ways and Means (1802) |
| Structure reformed by | Legislative Reorganization Acts of 1946 and 1970 |
| Date | First select committees 1789, first standing committee 1802 |
| Location | Capitol and House and Senate office buildings |