Sen. Elizabeth Warren (D-Mass.) speaks to members of the media Wednesday in the Russell Senate Office Building rotunda in Washington. (Andrew Harrer/Bloomberg News)

By a vote of 49 to 43, Senate Republicans on Tuesday night formally silenced Sen. Elizabeth Warren (D-Mass.) during the debate over the nomination of Sen. Jeff Sessions (R-Ala.) to be attorney general.

Invoking a seldom-used Senate rule, Republicans put Warren in her seat. Undeterred, she left the chamber, reached far beyond the nighttime audience of C-Span junkies, and broadcast to millions tough criticism of Sessions, leveled in statements by former senator Edward M. Kennedy (D-Mass.) and Coretta Scott King.

What happened Tuesday night and what can it tell us about legislative politics and the state of the Senate?

Here’s how Republicans forced Warren to take her seat

Senate debate is governed by Rule 19, which includes a rarely invoked clause empowering the presiding officer to enforce standards of decorum on the Senate floor:

  1. No Senator in debate shall, directly or indirectly, by any form of words impute to another Senator or to other Senators any conduct or motive unworthy or unbecoming a Senator.

At issue last night was Warren’s reading from materials entered into the congressional record, including statements from Kennedy and King, the widow of civil rights icon Martin Luther King Jr., when the Senate in 1986 considered Sessions for a seat on the federal bench.

Warren quoted Kennedy, who had called Sessions a “disgrace,” leading the Senate’s presiding officer to warn Warren that she was on the verge of breaking Rule 19.

When Warren then read from King’s letter, Senate Majority Leader Mitch McConnell (R-Ky.) called her to order. Warren asked to continue her remarks — suggesting that she was quoting from a letter introduced into the record and thus not directly impugning the motives of a fellow senator. McConnell objected (a right of any senator), and the presiding officer ordered Warren to take her seat. Warren lost her appeal on a party-line vote.

Sen. Elizabeth Warren (D-Mass.) was stopped from speaking on the Senate floor about Attorney General nominee Jeff Sessions on Feb. 7. "I am surprised that the words of Coretta Scott King are not suitable for debate in the United States Senate," Warren said. (Reuters)

As McConnell later explained: “She was warned. She was given an explanation. Nevertheless, she persisted.” The optics of Republicans mansplaining Warren will surely encourage Democrats to relaunch their attack that the GOP was waging a “war on women.” Moreover, instead of silencing Warren, Republicans empowered Warren to broadcast her opposition to Sessions to at least 6 million viewers on Facebook. Taking a play from E.E. Schattschneider’s 1960 “The Semi-Sovereign People,” Warren “expanded the scope of conflict” to draw millions into her fight against Trump’s nominee.

Three lessons from Tuesday’s parliamentary spat

First, Tuesday night’s spat reminds us that a Senate majority retains the power to interpret its rules as it sees fit. Despite rules that empower the minority party to slow down and often derail the majority’s agenda, molding rules remains an important tool of a cohesive majority party. In this case, a majority interpreted Rule 19 to cover breaches of decorum that arise from reading someone else’s words on the Senate floor.

The specifics of Tuesday’s appeal are unimportant. More significant is Republican willingness to impose an interpretation of its rules with the effect of amplifying partisan conflict and ensuring future fireworks. That’s precisely the dynamic that underlies a Senate majority’s capacity to “go nuclear” to ban the filibuster: reinterpret the rules to serve a party’s immediate advantage.

Second, fallout from the spat — both online and back on the Senate floor on Wednesday — ironically also signals the limits of the power of a Senate majority party.

Republicans wanted quick and quiet confirmation of President Trump’s nominees: No substantive action on the party’s agenda can occur without Trump’s team in place. Instead, Tuesday’s vote empowered Democrats to rewrite today’s headlines around McConnell’s words — framing Republicans as anti-women and highlighting Democrats’ criticism of Sessions.

Third, the spat highlights the Senate’s uneven enforcement of its rules. For many, this smells funny: Why wasn’t Sen. Ted Cruz (R-Tex.) silenced in the summer of 2015 when he all but accused McConnell on lying on the Senate floor?

Lax enforcement of rules, however, is precisely how the Senate typically keeps an even keel: Most of the time, senators and leaders do not fully exploit the chamber’s formal rules. Normally, they don’t have to. Instead, senators try to make things work by securing every senator’s consent on a path forward. Calling for votes and enforcing rules signals that the Senate — by its own standards — is failing.

Who’s the guilty party from last night’s spat?

Hard to say. Warren clearly thought she was in the right to read from the documents entered into the record. She didn’t back down when warned that she was broaching the blurred line of crossing Rule 19. But neither did McConnell seem to try to work things out short of leading his conference to silence a female colleague.

In less partisan times, senators have managed to smooth the waters, thus keeping the chamber functioning. That no longer seems to be the name of the game in the Senate.

Last week, Senate Republicans suspended their rules to force contested nominees to the floor. This week, Republicans silenced a colleague. Democrats blame the GOP for running roughshod over Democrats’ rights. Republicans protest Democrats’ unwillingness to cooperate.

But Senate Republicans will need Democratic consent to get much done this and next year. Indeed, voters will hold Trump and his Republican majority for accountable for Congress’s performance, even if Republicans blame Democrats for gumming up the works. The effect and duration of this new Republican majority hangs in the balance.