In the wake of GOP filibusters of all three of President Obama's nominees to the D.C. Circuit Court of Appeals, the Senate Thursday changed its rules to bar filibusters against all judicial nominations (except those for the Supreme Court) and all executive branch nominations. Here's what you need to know.

So what, precisely, just happened?

A brief history of the filibuster.

The Senate voted, by a simple 52-48 majority, to ban filibusters against all nominees except those to the Supreme Court.

How did they do that, technically speaking?

Gettin' technical. (Sarah L. Voisin/The Washington Post)

A cloture vote was held on D.C. Circuit Court nominee Patricia Millett, who failed to get 60 votes. The presiding officer of the Senate — Senate president pro tempore Patrick Leahy (D-Vt.), this time around — ruled that cloture had failed to be invoked.

Senate Majority Leader Harry Reid (D-Nev.) objected, arguing that for non-Supreme Court nominations, a simple majority was all that's required to invoke cloture. The Senate parliamentarian — acting through Leahy — ruled Reid's objection out of order. Reid appealed to the entire Senate, which voted by a simple majority in Reid's favor. That, alone, changed the Senate rules to reflect Reid's objection.

For more technical details, see my interview with filibuster expert Greg Koger.

Wait, didn't we see this before, when Republicans were in charge?

Sen. Trent Lott (R-MS), center, coined the term "nuclear option." (Matthew Cavanaugh/Getty Images)

Yep. There was discussion of changing  the Senate's rules by a simple majority vote to ban judicial filibusters in 2005, when Senate Majority Leader Bill Frist grew frustrated with the Democratic minority's repeated filibusters of appeals court nominees like Janice Rogers Brown. This option was first raised in 2003 by then-Sen. Trent Lott, who gave it the "nuclear" appellation.

I thought you could only change the rules on the first day.

Senate president pro tempore Patrick Leahy (D-Vt.) (Melina Mara/The Washington Post)

That's a myth, actually, as Thursday showed quite vividly. As the University of Miami's Greg Koger and Sergio Campos explain here, there are a number of ways the Senate can change its rules mid-session. We chose option #4.

All right, so it's allowed. Does this mean that the filibuster on legislation is the next to go?

Hard to say, but our own Ezra Klein certainly thinks so. For what it's worth, McConnell has said he'll repeal the filibuster entirely when Republicans are in the majority, a threat his camp reiterated Thursday. And the executive nomination change is huge, too, and makes it a lot easier for Obama to hire and fire people.

Who are these nominees that'll go through now?

Georgetown Law Center professor Nina Pillard, rumored to be among Obama's picks for the D.C. Circuit. (American Constitution Society)
Georgetown Law Center professor Nina Pillard, one of Obama's nominees for the D.C. Circuit. (American Constitution Society)

Brad has a full rundown here. Here's his recap of the three D.C. Circuit picks:

-- Patricia Ann Millett: A partner at Akin Gump and former assistant solicitor general during the Clinton and Bush administrations, she's argued more than 30 cases before the Supreme Court. Fellow Supreme Court lawyer Tom Goldstein called her “completely objective and non-ideological in a way that should make even Republicans smile.” But she's also clearly a Democrat, having donated $52,600 to the party in the 2008 and 2012 elections.

As a bonus, you can see her speak favorably about Supreme Court Chief Justice John Roberts's decision to uphold Obamacare here.

-- Nina Pillard: A Georgetown professor who specializes in gender discrimination and workplace issues. She famously argued a case that opened the Virginia Military Institute to women and, in 2003, successfully defended an aspect of the Family Medical Leave Act before the Supreme Court. (Some Republicans had taken issue with Pillard's views connecting reproductive rights with gender equality.)

-- Robert L. Wilkins: A current District Court judge in Washington who was confirmed by the Senate on a voice vote in 2010. He's a former public defender who famously (and successfully) sued the Maryland State Police after being pulled over by state troopers. That case launched a number of class-action lawsuits over racial profiling in the state.

Also, Mel Watt, a Democratic congressman from North Carolina who Obama nominated to run the Federal Housing Finance Agency, which oversees Fannie and Freddie, has been filibustered, and will now be confirmed easily.

What's the D.C. Circuit Court of Appeals?

Robert Bork, then a judge on the D.C. Circuit Court of Appeals, is sworn in for his Supreme Court confirmation hearing before the Senate Judiciary Committee in 1987. (John Duricka/AP)

The D.C. Circuit is one of 12 regional Courts of Appeals that handle cases from District Courts, which are the trial courts for civil and criminal cases conducted at the federal level. There's also a Court of Appeals for the Federal Circuit, which handles cases dealing with patents, claims against the federal government, international trade and other specialized matters, regardless of where they arise geographically.

Other regional Courts of Appeals span multiple states; the First Circuit, for instance, covers New Hampshire, Maine, Massachusetts, Rhode Island, and Puerto Rico. The D.C. Circuit's geographic jurisdiction is the smallest of any federal Court of Appeals, given that it doesn't cover any area outside the District of Columbia.

So it's the least important federal appeals court there is, right?

More than a decade before joining the Supreme Court, Elena Kagan (left) was nominated by President Bill Clinton to the D.C. Circuit, though her confirmation never came up for a vote. (Sharon Farmer/AP)

Hardly. Important stuff happens in D.C. In particular, federal administrative agencies make their decisions here, and when people object, their appeals sometimes make it to the D.C. Circuit, often going there directly without passing through the District Court. Shortly after leaving the D.C. Circuit Court to become Chief Justice, John Roberts wrote a law review article noting that one-third of the cases the court takes deal with federal agency decisions, and two-thirds involve the federal government in some civil capacity. By contrast, only 5 percent of cases nationally do. The D.C. Circuit, he concluded, is "a court with special responsibility to review legal challenges to the conduct of the national government."

That's why its judges are disproportionately likely to end up on the Supreme Court. In addition to Roberts, Ruth Bader Ginsburg, Clarence Thomas, and Antonin Scalia all served on the D.C. Circuit before being elevated to the Supremes. In 1999, Associate Justice Elena Kagan was nominated for a spot on the Court but didn't get a Senate vote; the seat ended up going to Roberts. The other four members of the court served on other Courts of Appeals (Stephen Breyer at the First Circuit, Sonia Sotomayor at the Second, Samuel Alito at the Third, and Anthony Kennedy at the Ninth); the D.C. Circuit, then, has as many justices as all other Circuits combined.

What sorts of cases is it going to rule on going forward?

Obama's EPA director nominee Gina McCarthy, whose life the D.C. Circuit could make very difficult if it so chooses. (Alex Brandon/AP)

Perhaps the biggest have to do with environmental regulations and Dodd-Frank law implementation.

Last year, the EPA proposed standards for new power plants that would basically make it impossible to build more coal plants going forward, though the rules have been delayed and may be changed. It's also going to issue rules limiting emissions from existing power plants that, if sufficiently aggressive, could lead to huge cuts in emissions. For example, the National Resources Defense Council has proposed a plan that would reduce total U.S. carbon emissions by 10 percent, and power plant emissions by 26 percent. Given the small chance of Congress passing a cap and trade system or carbon tax, this and other elements of the climate plan he laid out in June could be the most significant action on climate change to come out of Obama's presidency.

Court challenges to those rules are expected. The initial form of the new plants rule garnered some criticism. One energy industry lawyer, for instance, said, "A lot of people, myself included, think this approach is almost certain to get struck down in court." And as with most regulatory appeals, those cases are likely to go to the D.C. Circuit. That's why Jonathan Chait has argued that the D.C. Circuit Court nomination battles are really, at the end of the day, about climate change.

Meanwhile, as Haley Sweetland Edwards has explained in her great piece on the financial regulatory process, most of Dodd-Frank needs agency action to take effect. That process is heavily influenced by pressure from financial industry lobbyists, and even when regulations are approved by agencies, they're often in danger of being struck down in court.

For example, a rule the Commodities Futures Trading Commission establishing "position limits" — which constrain the amount bankers can bet on commodities, and are meant to tamp down on speculation and reduce the amount of risk banks take on -- was struck down by the D.C. Circuit, in a ruling turning on the meaning of the phrase "as appropriate." More cases like that are expected, and having three Obama appointees in place to rule on them could result in less pro-industry rulings going forward.

Whoa, that's basically Obama's whole non-health-care policy agenda right there.

Yeah…pretty much. (Jason Reed/Reuters)

I know, right?

So why didn't he appoint people earlier?

A very good question, but one without a lot of good answers. In late 2010, Obama did appoint Caitlin Halligan, a New York litigator who is now general counsel for the Manhattan DA's office, to Roberts's old spot on the D.C. Circuit Court. But her nomination languished, and earlier this year Republicans successfully filibustered an attempt to bring her up for a vote. Grassley objected to work Halligan did as New York state's solicitor general targeting gun manufacturers. Shortly thereafter, she asked Obama to withdraw her nomination.

But it took Obama a year and a half to nominate Halligan, and until June 2012 to nominate Sri Srinivasan to the D.C. Circuit Court, whose seat was vacant when Obama took office. Indeed, as the above chart from a recent Congressional Research Service report shows, Obama hadn't nominated anybody to fill 10 out of the 17 existing appeals court vacancies at the end of his first term, or 40 out of the 64 district court vacancies.

That's why some liberals have criticized Obama for dawdling on nominating federal judges. One likely reason is vetting concerns. Obama's administration has a notoriously lengthy and grueling vetting process for both judicial and executive nominees.

Is he actually dawdling?

Douglas Ginsburg, a D.C. Circuit judge who took senior status in 2011 and whose spot has still not been filled. (NYU Law)

Yes. Russell Wheeler at the Brookings Institution has a fantastic infographic showing that Obama took longer than former President George W. Bush to appoint both district court and appeals court judges, and unlike Bush and former President Bill Clinton, he had more vacancies after his first term than were there when he took office.

Then again, the average time from nomination to vote, and the confirmation rate has increased for district court nominees (though not for appeals court nominees), compared to under Bush, which one can probably attribute to Senate objections. It's worth keeping in mind, though, that Bush faced a Democratic Senate for many of his years in office, and Obama has always had a Democratic majority (and for a while had a filibuster-proof one), which should boost his confirmation rates:

Note: Much of this post is borrowed from an earlier post I wrote. Efficiency is important!