Each Congress is elected for a two-year term and holds two annual sessions. During that time, as many as 20,000 bills might be introduced, but only 5 percent to 10 percent of them are actually signed into law. While some may pass through Congress rather quickly, others lead to lengthy hearings in the subcommittees or committees and protracted debates on the floor of the House and Senate. Few legislative proposals emerge from the process exactly as they were first written. What many have called the "dance of legislation" is influenced by partisan politics, the lobbying of interest groups, and public opinion.
A bill is introduced
With the exception of revenue or tax bills, which must originate in the House, legislation can be introduced in either the House or the Senate; sometimes identical bills are introduced in both houses. The majority of bills are written by the executive branch. In the State of the Union address, the president presents a legislative program for the coming session. Members of Congress, usually through their staffs, draft legislation as well. Very often, an interest group that wants a particular law passed will work with congressional staff or the administration to get a bill introduced. A Senate or House member may sponsor (introduce) a bill, and the bill may have numerous congressional cosponsors. Each bill is assigned a number (and the prefix HR in the House or S in the Senate) by the clerks of the House or the Senate. Bills are then sent to the appropriate committees by the Speaker of the House or the Senate majority leader.
A bill in committee
A bill goes to one of the standing committees and then to a subcommittee, as determined by the committee chair. The subcommittee holds hearings on the bill, taking testimony from its supporters and opponents. After the hearings, it usually issues a report that is either favorable or unfavorable to the bill. Or it may report out an amended or changed bill or rewrite the original bill entirely as a committee print. The standing committee usually accepts the recommendation of its subcommittee.
A bill favorably reported out of a Senate committee is put on the calendar for floor action. The bill's sponsors schedule when the debate on the bill will begin through a unanimous consent agreement. The process is different in the House. Here bills must first go through the Rules Committee, which decides when the full House will hear the bill, if the bill can be amended from the floor, and how much time will be allowed for debate.
A bill before the full House and Senate
The procedures for debating and voting on legislation are different in the House and the Senate. In the House, each member is allowed five minutes to speak on a bill. If amendments are allowed by the Rules Committee, these must pertain to the bill itself. Amendments are accepted or rejected by a vote of the members present. In the Senate, there is no time limit on debate. A senator who wants to delay action on a bill or kill it altogether may use a tactic called a filibuster. This is a marathon speech that may go on for hours with the senator yielding the floor only to members who support his or her position. A filibuster can be cut off only through cloture. A petition from a minimum of 16 senators is needed for a cloture vote, and 60 senators must actually vote for cloture to end a filibuster. Even then, each senator can still speak for one hour. The Senate also puts no restrictions on the nature of the amendments to a bill. Amendments completely unrelated to the bill are called riders. A senator may add an amendment to a highway bill for a new veterans' hospital in his or her state, for example.
Bills are passed in the House and Senate by voice vote (either "aye" or "no"), standing vote (members must stand up to indicate yes or no), or roll call vote (each member's vote for or against a bill is recorded).
Factors influencing voting decisions
Legislators are influenced by a variety of factors in making their voting decisions. The unwritten rules of Congress certainly have a role. Through serving on committees, members develop an expertise in a particular field. Other representatives or senators are likely to accept their judgment that a bill merits their support. They will expect the same deference for a piece of legislation in their area of specialization. Legislators often vote for each other's bills when a bill does not affect their constituency. This is a political technique known as logrolling. It is frequently used to advance pork-barrel legislation — bills designed to benefit a congressional district or state through the appropriation of federal funds. Highway construction, river and harbor improvements, and military base siting are typical examples of pork-barrel projects. A type of pork-barrel spending is an earmark. Although there is little agreement on a definition, most in Congress would agree that the term refers to a specific spending proposal included by a member in an appropriations bill that does not get full scrutiny.
Party loyalty is probably the most important voting factor. In the 1990s, more than 80 percent of the members of Congress voted according to party affiliation. Interest groups provide information to and put pressure (sometimes subtle, sometimes not) on a legislator to vote one way or another. Industry trade associations, unions, environmental groups, and political action committees employ lobbyists, paid professionals who try to influence legislation. The role of these groups is significant because they also contribute money and sometimes volunteers to election campaigns. Also, a call from the president to vote for or against a bill is hard to resist. The president can appeal for the good of the nation or party loyalty, promise to actively support legislation the member of Congress wants, or threaten to cut off campaign funds.
Constituents, the voters whom the legislator represents, also exercise considerable influence. A congressperson or senator who consistently votes against what the majority of the "folks back home" wants will soon be out of office. Personal beliefs are certainly a factor in voting decisions. If a member of Congress holds a strong position on an issue, no amount of pressure from party members, lobbyists, the president, or even constituents will make a difference.
The conference committee and action by the president
Similar bills that have been passed independently by the House and the Senate go to a conference committee to resolve the differences. If the committee cannot work out a compromise version, the bill is dead for that session of Congress. The bill that comes out of the committee is sent to both houses for a vote, and it cannot be amended from the floor. If the bill is approved by the House and the Senate, it is sent to the president for final action.
A bill becomes a law when signed by the president. If the president vetoes a bill, Congress can override the veto by a two-thirds vote of both houses. There are many reasons for a president to reject legislation. For example, although the president may be supportive of the bill's main purpose, he may decide that it contains unacceptable riders. If the president does not sign or veto a bill within ten days, the bill becomes law. On the other hand, the bill is dead if Congress adjourns within this ten-day period. This is known as a pocket veto. In 1996, Congress gave the president line-item veto power, which meant he could reject specific spending items within a larger bill. The Supreme Court struck down this attempt to increase presidential discretion two years later, however, in Clinton v. City of New York.