How a Bill Becomes a Law

Any member of the House of Representatives or the Senate may introduce a bill that can become law. The bill is assigned a number (such as H.R.1 or S.1, depending on the chamber of its origination), labeled with the sponsor's name and published. Most bills will have co-sponsors. More co-sponsors are generally desirable. Bills usually have names which have been carefully crafted to convey the best "spin."

Committee System

Membership on committees is split between the parties as determined by the majority party in each house.  Committee members rank in order of their appointment to the full committee.  The senior ranking member of the committee of the majority party is usually elected as Chairman or Chairwoman.  The committee chairperson is very important to the legislative process since he or she determines the docket and order, and assigns the bill to a subcommittee.  Committees and subcommittees review proposed legislation, experts are consulted, feedback is obtained from government agencies, and public hearings are conducted to fully understand key issues on both sides. 

After receiving a bill, the Speaker of the House or the Presiding Officer in the Senate submits the bill to the appropriate committee. Due to the high volume and complexity of its work, Congress divides its tasks between approximately 250 committees and sub-committees. The House and Senate each have their own committee system, which are similar. There are 22 committees in the Senate and 25 committees in the House of Representatives.  A bill may be sent to more than one committee, and sometimes parts are sent to different committees.

A member usually seeks election to a committee. Eventually, content is determined and the full committee votes on the bill.  If the committee passes the bill, it then holds a 'mark-up' session where revisions are made. If amendments are substantial, the bill is rewritten, and a 'clean bill' is sent to the House or Senate in place of the original version. That chamber then reviews all changes made by the committee before conducting a final vote.

Reporting a Bill

After a bill is reported, the committee provides the originating chamber with a statement detailing why they favor or disfavor the bill and defending any amendments. The bill is then placed on the calendar.

The Speaker of the House decides which bills receive attention and in what order. In the Senate, the Majority Leader decides which bills make it to the floor and when.  For this reason, control of the House or Senate by a party is very important. The bill is then debated.  In the House, the Rules Committee decides the limits of debate, and there must be a quorum (218 members present) to vote. In the Senate, debate is unlimited, and sometimes even a single member may block legislation by conducting a 'filibuster' so that debate lasts so long that the bill doesn't pass.  Sixty senators must vote to close debate in order to vote on a bill.


After debating is completed, voting begins. Generally, passage requires a simple majority of a quorum.  After a bill is passed in one chamber, it is sent to the other to be voted on, unless the other chamber is reviewing a similar bill. Both the House and the Senate must pass a bill for it to be sent to the President to sign into law.

A bill not passed by both chambers is dead. If the House and Senate approve two similar but separate bills, the two bills are sent to a Conference Committee, made up of senior members of both chambers (chosen by leadership for each such occurrence) who work to reach a compromise bill. The Conference Committee writes a report on the final version, which is then voted on by both chambers.  If passed, the bill is sent to the President for final review.

Becoming Law

The President of the United States must decide whether to sign a bill or to veto it.  If the bill is signed, it becomes law.  If a bill is vetoed, the President sends it back to its original chamber with his reasons for doing so. Congress may override a veto by a two-thirds vote in both chambers, and the bill becomes law. 

If Congress adjourns within 10 days after the bill reaches the President and the President has not signed it, it is vetoed automatically. This is called a 'pocket veto.' However, if Congress remains in session for the full 10 days, the bill becomes law.