Cloture

Cloture is the procedure for ending debate in the Senate. Under current Rule XXII, three-fifths of the Senate, ordinarily 60 senators, must vote to invoke cloture before a vote on the underlying question can occur.

For more than a century after the founding, the Senate had no formal way to end debate. A determined minority could delay or block legislation indefinitely through a filibuster. In 1917, prompted by the obstruction of a bill arming American merchant ships against German submarines, the Senate adopted Rule XXII. The new rule allowed two-thirds of senators to vote for cloture and end debate. In 1975, the threshold was lowered to three-fifths of the Senate, or 60 votes when all 100 seats are filled. The cloture procedure works in stages. A cloture motion must be filed by 16 senators. Two days later, the Senate votes. If 60 senators agree, debate is limited to 30 additional hours and then a vote on the underlying matter is required. If cloture fails, debate continues. The Senate has carved out exceptions to the 60-vote threshold over time. Budget reconciliation, which deals with revenues, spending, and the debt limit, requires only a simple majority. The so-called nuclear option, used by Senate Democrats in 2013 and Senate Republicans in 2017, lowered the cloture threshold for executive branch and judicial nominations, including Supreme Court nominations, to a simple majority. For most legislation, the 60-vote requirement remains. The result is that in a closely divided Senate, almost nothing passes without bipartisan support. Whether that is a feature or a flaw depends on which side of a given vote a senator is on. Cloture's most famous invocation came on June 10, 1964, when the Senate ended the long filibuster against the Civil Rights Act. The vote ended the longest filibuster in Senate history and cleared the way for the most consequential civil rights legislation since Reconstruction.