President Obama on Tuesday announced the nomination of two attorneys to fill seats on the National Labor Relations Board that were vacated by Republicans.

Harry Johnson III and Philip Miscimarra, partners at Arent Fox and Morgan, Lewis & Bockius, respectively, would serve five-year terms on the five-person board. Obama re-nominated Mark Gaston Pearce to serve as chairman for a second term. Pearce has served on the board since 2011 and his term will end on August 27. Neither Johnson nor Miscimarra immediately responded to a request for comment.

Johnson, based in Arent Fox’s Los Angeles office, focuses his civil litigation practice on the management-side, with an emphasis on wage-hour class actions. He has represented clients before the NLRB in union and labor disputes. Before joining Arent Fox in 2010, he was an associate and subsequently a partner at Jones Day.

Miscimarra, a Chicago-based partner at Morgan Lewis, practices in labor and employment litigation and co-chairs a labor and employment sub-practice that focuses on labor issues that arise from mergers, acquisitions and other business transactions.

"Phil’s experience with clients and his work before the Board will be a great asset to the NLRB if he is confirmed," Morgan Lewis chairman Francis Milone said in a written statement.

Obama has struggled to fill the labor board, which requires three members to constitute a quorum. The composition of the board has come under scrutiny in recent months as federal appellate courts assess whether the president’s use of recess appointments to keep the board functioning violated the constitution.

In January 2012, Obama appointed three people—Sharon Block, Terence Flynn and Richard Griffin—to the NLRB via recess appointments. Republicans criticized the moves, saying that Obama unlawfully bypassed the advice-and-consent role of the U.S. Senate to review candidates for federal agency slots. (Flynn, a Republican, has since resigned from the board. Pearce, Block and Griffin are Democrats.)

A three-judge panel of the U.S. Court of Appeals for the D.C. Circuit in January this year unanimously declared Obama’s appointment of Block and Griffin to the NLRB unconstitutional. The Senate, the appeals court said, was not officially in "the recess," as required by the Constitution.

"Allowing the President to define the scope of his own appointments power would eviscerate the Constitution’s separation of powers," then-Chief Judge David Sentelle wrote for the D.C. Circuit panel.

Federal appellate courts in Philadelphia and Richmond are also reviewing the constitutionality of the appointments. In the D.C. Circuit, dozens of labor cases are on hold pending the resolution of the legal fight. The NLRB announced in March that the agency would petition the U.S. Supreme Court for review of the D.C. Circuit panel ruling.

Former NLRB member and Seyfarth Shaw counsel Marshall Babson said Johnson and Miscimarra are both "very bright, very experienced" attorneys with "considerable experience dealing with labor and employment matters and the National Labor Relations Board."

Babson said he was unaware of anything in the attorneys’ work history that might disqualify them from serving. "Having a fully confirmed NLRB with five confirmed board members in this case would be a good thing for the agency and a good thing for everyone the agency serves," Babson said. "I think that it’s good news that experienced and qualified individuals have had their names sent to the Senate for consideration."

White House spokesman Jay Carney told reporters the Senate should move "efficiently" on Obama’s nominations to the labor board.

"These nominations… would bring the NLRB up to full operating level, ensuring that it continues to function and fulfill its responsibilities to look after workers’ rights," Carney said at a press briefing. "The two nominees, Harry Johnson and Philip Miscimarra, are Republican nominees and you would have a balanced, bipartisan board, and we urge the Senate to move on those nominations efficiently."

Matthew Huisman can be contacted at NLJ reporter Mike Scarcella contributed to this report.