What Is a Filibuster? Everything to Know About the Senate's Most Contentious Rule

Whenever the gavel switches from the hands of one party to the other in the Senate, lawmakers engage in a public round of debate about a long-established political tradition — the filibuster.

With the country split along party lines and the Senate reflecting the same divide, the filibuster effectively stalls most major legislation. As its use rose in popularity, this congressional tactic has had a lasting effect on modern policy making. 

Here is what you need to know about the filibuster: how it works, why there's always talk about eliminating it and some notable filibusters in history.

What Is a Filibuster and How Does It Work?

The filibuster is among the Senate’s “most distinctive procedural features,” according to the Congressional Research Service.

Many believe that this political procedure has been a part of American democracy since day one. In fact, it emerged in 1806 when the Senate — at the advice of Vice President Aaron Burr — got rid of the previous question motion, a provision that allowed a simple majority to cut off debate and force a vote. The term, filibuster, became popular in the 1850s as a way to ensure debate over legislation in the Senate.

It is a practice any lawmaker can take to slow down or block a bill from getting a vote on the Senate floor. Historically, senators would have to launch a talkathon on the chamber floor, which could theoretically last forever, to prevent voting on a bill.

Senators have famously stood at their desks for hours making their case, as the character played by Jimmy Stewart did in “Mr. Smith Goes to Washington” or as South Carolina Sen. Strom Thurmond did to stall the 1957 Civil Rights Act.

In the 1970s, the chamber changed the rules to make things more efficient. It allowed senators to simply voice their objections when others tried to move forward with legislation, without having to speak about their reasons.

Today, senators can merely signal their intent to object, even privately, and that’s enough for Senate leaders to take action. Leaders sometimes just drop the issue from floor consideration. At other times, they push ahead, taking cumbersome steps to cut off the filibuster and move forward with the proceedings.

What Can Break a Filibuster?

There are two ways to end a filibuster.

For the first, a senator could seek "unanimous consent" from the rest of the members to end a debate. If there is no objection, the Senate could proceed to a vote.

Or they resort to what's called a "cloture."

The cloture rule was adopted in 1917, and for many decades required a two-thirds majority, or 67 votes, to effectively end a filibuster. But in 1975, the rule was changed to 60 votes. 

Due to the change in the number of votes required for a cloture, the filibuster has become an increasingly popular tool for the minority party to create obstacles to legislation in the past four decades. Data from the Senate’s website shows that during the Obama era, 631 cloture motions were filed; when Trump was in office, 529 cloture motions were filed.

Once debate is brought to a close, senators can move forward with consideration of the measure at hand, amendments or even final votes.

Why Do Lawmakers Want To Eliminate the Filibuster?

Since senators can filibuster simply by expressing their intentions to do so, and the only way to end a filibuster is to have 60 votes to file a cloture, legislation is hard to pass on today’s Senate floor, especially when a party only holds a slim majority.

Because of this, the filibuster has been hailed as a way to let the minority's voice be heard. But as the country, and Congress, has grown more partisan, the filibuster has become a key weapon in what is often described as a procedural arms race in the Senate.

With each passing year, more and more senators threaten to wage filibusters to block legislation. Overcoming filibusters can take days, if not weeks.

Even without a senator holding the floor, filibusters have forced senators into all-night and weekend votes to advance legislation, as happened during passage of the Affordable Care Act.

“Filibusters and the prospect of filibusters shape much of the way in which the Senate does its work,” the CRS report said.

So, whoever holds the Senate majority would want to get rid of the long-standing tradition to make it easier for them to wield power in the chamber.

What Is the 'Nuclear' Option?

One way to bypass the filibuster and pass major legislation with a simple majority vote is through an arcane process called budget reconciliation. This procedure is limited, however, because it deals solely with federal budget issues and can only be used once a fiscal year.

To eliminate or significantly change the filibuster, lawmakers can trigger the “nuclear option,” because it would “blow up” the existing tradition. The nuclear option would allow legislation to pass with a simple majority of 51 votes. 

At the time, the nuclear option may seem a desirable option for the majority party in the Senate, because it will allow them to pass legislation much easier. However, in years of closely divided Congress, members of the majority party are cautious not to seek short-term advantages at the cost of long-term interests, because they fear that the change may eventually come back to hurt them when they return to the minority, which may happen in merely two years.

Can the Senate Change the Filibuster Rules?

It takes 51 votes to change the Senate rules, a tall order at most times but especially in the now evenly split 50-50 Senate. Democrats hold a slim majority because Vice President Kamala Harris can be a tie-breaking vote.

But senators have changed the filibuster rules before.

Fed up with the Republicans stonewalling Barack Obama’s executive and judicial branch nominees, Democrats led by then-Sen. Harry Reid of Nevada changed the rules to set a simple 51-vote threshold for confirming people in those positions. ′

Republicans under Sen. Mitch McConnell of Kentucky went a step further, eliminating the filibuster for Supreme Court nominees, which allowed Donald Trump’s three high-court justices to be confirmed.

While several Democrats and advocacy groups call for ridding the Senate of the filibuster on legislation, there does not appear to be enough support from Democratic senators at this time to do so.

President Joe Biden has voiced support for a return to the “old days,” as he put it, of the talking filibuster, forcing senators to stand at their desks and articulate their opposition to the proceedings, as was the practice when he first joined the Senate decades ago.

“You’ve got to work for the filibuster,” he said in a March ABC News interview.

The idea has support from Democrats who see it as a possible alternative to fully ending the filibuster practice. But it still poses risks, and Democratic leaders have been reluctant to move toward that option.

Several Republican senators, particularly those considering running for president in 2024, might see political advantage to seizing the floor to rail endlessly against White House priorities. The filibusters could also stall action on other Democratic priorities, including Biden’s nominees.

What Are Some Notable Filibusters in History?

Sen. Strom Thurmond holds the record for the longest filibuster at 24 hours and 18 minutes, opposing the Civil Rights Act of 1957. Thurmond was among a group of white southern Democrats, along with Sen. Robert Byrd, William Fullbright, Sam Ervin, and Richard Russell, who challenged civil rights legislation. Thurmond was well-prepared for the filibuster. He took a steam bath earlier in the day to get rid of excess liquid and went to the chamber floor with cough drops and malted milk tablets. He also filled in some of his time by taking questions and remarks from sympathetic senators and had his aides waiting in the cloakroom in case of an emergency. Nonetheless, Thurmond’s filibuster did not change a vote, and the Civil Rights Act passed successfully. 

The Senate website documents that at midnight on a spring day in 1908, during a filibuster against an adoption of a conference report, Robert M. La Follette, a Wisconsin senator, sent a page to the Senate restaurant for a turkey sandwich and a glass of milk fortified with eggs. The kitchen staff were not happy with the prospect of working till the next morning, so they might have served La Follette unrefrigerated eggnog. As the senator took a big gulp, something tasted funny. Shortly after, he began feeling sick and sweating profusely, and thus had to leave the floor. An analysis of the drink revealed that the mixture contained enough toxic bacteria that could have killed La Follette if he had drunk the whole glass.

In 1935, Louisiana senator Huey Long filled his 15 and a half hours on the floor with reading everything he could get his hands on. From reading Shakespeare to describing recipes of fried oysters to analyzing every section of the Constitution, Long was described as “the most colorful, as well as the most dangerous, man to engage in American politics.” He was filibustering to keep the provision that requires Senate confirmation for the National Recovery Administration’s senior employees. After noticing that many of his colleagues were dozing off, Long suggested to Vice President John Nance Garner to wake them up. The latter replied, “That would be unusual cruelty under the Bill of Rights.”