Dive Brief:

• Judge Cornelia Pillard will participate in the D.C. Circuit Court's en banc hearing on the Clean Power Plan next week, according to a court document.
• Pillard and Judge Merrick Garland did not participate in the D.C. Circuit's decision in May to skip a three-judge panel and proceed directly to an en banc hearing, but a Thursday notice to parties in the case informed them that only Garland, who is nominated to the Supreme Court, will recuse himself from the hearing.
• Pillard's move brings the number of judges hearing the case to 10, opening the possibility of a 5-5 deadlock on the carbon rules. That would likely mean a Supreme Court hearing, where a 4-4 split is currently possible to to a vacancy. Legal experts, however, expect the seat to be filled by the time the case reaches the high court.

Dive Insight:

At this point, surprises are expected in the Clean Power Plan's legal journey. 

Earlier this year, the Supreme Court shook the power industry when it announced a judicial hold on implementing the rules until court challenges concluded. Then the D.C. Circuit announced it would hear the case en banc, a rare move that reportedly blindsided EPA officials. 

At the time, court documents simply indicated that Pillard "did not participate," leaving most observers to conclude she would sit out the hearing as well. But with similarly scant explanation, the court clerk wrote to parties on Thursday that only Garland would recuse himself from the hearing. 

Pillard's decision opens up a number of complicated — if unlikely — legal scenarios for the rule. 

If the D.C. Circuit deadlocks in a 5-5 decision, the case would be kicked upstairs to the Supreme Court — a likely outcome in any decision, given the high profile of the case. But the Supreme Court currently has only eight judges, with late Justice Antonin Scalia's seat still vacant due to Congressional objections to Garland's nomination to the bench. 

If that seat remains open, the high court could also deadlock 4-4, which would typically mean the D.C. Circuit decision would stand. In the case of a split there, energy lawyers say the Clean Power Plan would stand, as no court will have actively struck it down.

"Industry might argue that somehow the stay decision matters," said Brian Potts, a partner at Perkins Coie, "but my position is that a stay is in place only until there’s final judicial resolution and if there’s a Supreme Court tie or the court does not grant cert, that's a final judicial resolution, so the stay would have to be lifted."

Legal experts say that eventuality is unlikely. Due to the months it will take for a D.C. Circuit decision and subsequent appeals, the Supreme Court is not expected to take up the case before its Oct. 2017 term, when the vacancy could be filled. 

It's more likely, however, that the issue of a split will be irrelevant. Already, the nine judges expected to hear the case before Pillard joined were seen as friendly to the EPA, with five appointed by Democratic presidents and four by Republicans.

Pillard is an Obama appointee and was narrowly approved by the Senate in a 51-44 vote in 2013, with detractors labeling her one of the most "radical" judges to sit on the court, though most focused on her reproductive rights stances. (Among liberals, some have called her a "next Ruth Bader Ginsburg.")

"This is unequivocally bad for [CPP opponents]," Potts said. “I’ve always known her to be one of the more pro-EPA judges based on her decisions and political history."

The D.C. Circuit Court will hear arguments on the Clean Power Plan next Tuesday, Sept. 27 in Washington. For context and information on the case history of the other judges, read Robert Walton's D.C. Circuit primer.