Of all Congressional procedures, the filibuster is the most contentious.  Fittingly, the word itself is two derivations away from the Dutch word for privateer (vrijbuiter).  In the United States Senate, the filibuster rules allow any senator (or series of senators) to speak for as long as they like on any topic they choose.  Senators can only force the filibuster to end if three-fifths of them (about 60% of the Senate) invoke what’s known as cloture.  Frequently, that’s a tough task to achieve.  Indeed, the 1939 film Mr. Smith Goes to Washington depicted the filibuster as powerful enough to result in an attempted suicide.

Recently the filibuster, never far from the public consciousness, garnered an unusual amount of attention when Texas State Senator Wendy Davis deployed the dilatory tactic to successfully prevent a controversial abortion bill from being brought to a vote.  News of her 11-hour filibuster spread across the internet through Twitter and Facebook and, while that bill ultimately passed on July 12, it provided ammunition for both sides of the debate over the merits of the filibuster.

And the filibuster controversy (is the filibuster the last refuge of an obstructionist? Or a necessary check against the tyranny of the majority?) is set to flare again.  President Obama’s nominations to the Consumer Financial Protection Bureau, the Department of Labor, the Environmental Protection Agency, and the National Labor Relations Board are ripe for filibustering.  Faced with possible GOP filibusters, Senate Majority Leader Harry Reid may try to change the rules through the colorfully named nuclear option (also known as the constitutional option).  While 67 votes are usually needed to change a Senate rule, there is a way to change a rule with a simple majority.  Upon request, the Presiding Officer must make a ruling on whether Senate rules have been breached.  A Senator could request a review of the rule requiring 67 votes to change Senate procedures and, upon affirmation of that rule, Reid could then move to overrule the Presiding Officer’s decision and reduce the number of votes needed for a rule change.  Overruling the Presiding Officer of the Senate only requires a majority vote.  Once the number of votes needed to change Senate rules was reduced, a majority could then also lower the number of votes needed to end filibusters against judicial and executive branch nominees.

The nuclear option came into prominence in 2005, when Democrats were leading filibusters of President Bush’s judicial nominees.  Majority Leader Bill Frist threatened to end the filibusters with a change to Senate rules.  The potential crisis was averted when the Gang of 14–a group of seven Democrats and seven Republicans–promised not to filibuster President Bush’s nominees, except under “extraordinary circumstances.”  That agreement expired in 2007.

Historically, the filibuster was more of a theoretical option, rather than a common strategic tool for the minority group.  While Senate rules opened the possibility for filibusters in 1806, the first Senate filibuster did not occur until 1837.  The 1960s served as a turning point for the filibuster, when civil rights litigation prompted a flurry of filibusters, including a 75 hour filibuster by Senate Democrats opposed to the Civil Rights Act of 1964.  While it’s unlikely that President Obama’s current nominations would produce such a filibuster (the Senate has gotten in the habit of simply moving on to other business when a filibuster is threatened), Majority Leader Harry Reid is clearly frustrated with the procedure.  More than once in the past four years he has challenged the Republican use of the filibuster,  but only the coming weeks will reveal whether he’s frustrated enough to attempt to overhaul the way the Senate operates.