The Filibuster and Cloture

The filibuster was an accident. In 1806 the Senate dropped the previous question motion, its only way to cut off debate, on the advice that it was rarely used. Without it, any senator could talk indefinitely, and by the 1840s minorities had discovered they could block bills by refusing to stop. The Senate adopted its first cloture rule in 1917 after a filibuster against arming merchant ships, allowing two thirds of senators voting to end debate. In 1975 the threshold was lowered to three fifths of the full Senate, sixty votes.

Today a filibuster rarely involves talking. A senator need only signal an objection, and the majority leader files a cloture motion. Two days later the Senate votes, and if sixty senators agree, debate is limited to thirty more hours. Because nearly every significant bill now faces this threshold, the practical rule is that most legislation needs sixty votes in a hundred-member Senate. Talking filibusters still occur as protests, and in April 2025 Senator Cory Booker spoke for more than twenty-five hours, breaking Strom Thurmond's 1957 record.

The sixty-vote rule has been narrowed repeatedly. Budget reconciliation, trade agreements under fast-track, Congressional Review Act resolutions, and several other procedures are protected from filibusters by statute. In 2013 the Democratic majority used the so-called nuclear option, a ruling sustained by simple majority, to end filibusters on executive nominations and lower-court judges, and in 2017 the Republican majority extended it to Supreme Court nominees. Defenders of the filibuster say it forces bipartisan compromise and protects the minority. Critics say it lets a minority representing a fraction of the country block popular legislation, and proposals to abolish or restore the talking filibuster recur whenever control of the Senate changes.