Republicans in the U.S. Senate are challenging the president's recess appointments to a labor board by coming to the legal aid of a Washington state company.

The Senate GOP and businesses were incensed when President Barack Obama in January bypassed the Senate to fill three vacancies on the five-member National Labor Relations Board, and to appoint a director for the nascent Consumer Financial Protection Bureau.

Facing GOP opposition to his nominees, Obama made his picks despite a parliamentary tactic from Republicans to block any recess appointments by holding pro forma Senate sessions without conducting actual business. This kept the Senate officially in session. The Obama administration maintained the appointments are constitutional, challenging the legitimacy of such sessions.

The Senate GOP is hitching its constitutional objections to the appointments on a case pending before the Washington, D.C., appeals court from Noel Canning of Yakima, Wash., a bottling company hit with a Feb. 8 NLRB order to open collective bargaining with a union.

The suit is being used as a vehicle to challenge the appointments and any rules or regulation that comes from them. The U.S. Chamber of Commerce in March asked the D.C. appeals court, which handles litigation involving federal agencies, to intervene in order to present the constitutional question to the judges. The Chamber say the NLRB lacked authority to issue its order against Noel Canning because Obama's appointments are illegal, leaving the board without a quorum needed to conduct its business.

Senate Minority Leader Mitch McConnell, R-Ky., said his caucus decided to join a lawsuit to respond to Obama's unconstitutional action.

We had been looking for what we think is the best case, McConnell told the Washington Post. We think it's the appropriate case, the best case to do that.

Interestingly enough, the lawyer the GOP tapped to handle its friend-of-the-court -- or amicus -- brief is Miguel Estrada, a former George W. Bush administration attorney whose confirmation to the same D.C. circuit court was dashed by a Democratic-led filibuster.

I thought that Miguel's own experience with the confirmation process, that it might make particularly good sense for him to represent us in this particular undertaking, McConnell said.

The Senate minority's voice may be helpful when the court wades through the murky legal issues the challenge presents, such as when Congress is officially in or out of recess.

White House spokesman Eric Schultz told the Huffington Post, We are confident that the president's authority to make recess appointments will be upheld by the courts.