The Constitution requires that a quorum, or a majority of all Senators, be present to conduct business on the floor. Even though Senators have many responsibilities that frequently keep them from the floor, the Senate presumes that a quorum is present unless a quorum call demonstrates that it is not.
A Senator who has been recognized may suggest the absence of a quorum at almost any time; a clerk then begins to call the roll of Senators. Senators may not debate or conduct business while a quorum call is in progress. If a majority of Senators do not appear and respond to their names, the Senate can only adjourn or recess, or attempt to secure the attendance of additional Senators. However, quorum calls usually are ended by unanimous consent before the clerk completes the call of the roll and the absence of a quorum is demonstrated. The reason is that most quorum calls are not really intended to determine if a quorum is present.
The purpose of a quorum call usually is to suspend floor activity temporarily. If a Senator is coming to the floor to speak, a colleague may suggest the absence of a quorum until the expected Senator arrives. If the Senate finds itself confronted with unexpected procedural complications, if the Majority Leader needs to meet with several Senators on the floor about a possible unanimous consent agreement, if the floor manager of a bill wants to discuss a compromise alternative to an amendment another Senator has offered--for any of these or many other reasons, a Senator may suggest the absence of a quorum to permit time for informal consultations. The time consumed by many quorum calls permits intensive and productive discussions that would be far more difficult to hold under the rules of formal Senate debate.
The Constitution also provides that one-fifth of the Senators on the floor (assuming that a quorum is present) can demand a roll call vote. Since the smallest possible quorum is 51 Senators, the support of at least 11 Senators is required to order a roll call vote. A Senator who has been recognized can ask for "the yeas and nays" at any time that the Senate is considering a motion, amendment, bill, or other question. If a roll call is ordered, that is how the Senate will vote on the question whenever the time for the vote arrives. Thus, the Senate may order a roll call vote on an amendment as soon as it is offered, but the vote itself may not take place for several hours or more, when Senators no longer wish to debate the amendment.
The alternative to a roll call vote usually is a voice vote in which the Senators favoring the bill or amendment (or whatever question is to be decided) vote "aye" in unison, followed by those voting "no." Although a voice vote does not create a public record of how each Senator voted, it is an equally valid and conclusive way for the Senate to reach a decision.
(The information in this section was compiled under the authority and direction of the Secretary of the Senate, Washington, DC 20510. Questions regarding content on this site can be directed to the Office of the Secretary Webmaster at webmaster@sec.senate.gov.)
