The National Labor Relations Board’s vote Wednesday to move forward on a contentious union election rule could rest on the shoulders of one man.

Brian Hayes, the lone Republican member of the labor board, threatened to resign or withhold his participation after the NLRB began to push forward on the rule. The possibility of his declining to take part in Wednesday’s vote — perhaps by not attending — has raised questions about whether the NRLB has the power to move forward with the proposed regulation.

{mosads}The Supreme Court has ruled that the NLRB needs a quorum of three to issue regulations.

The NLRB would not say whether Hayes would be attending the vote, which will be followed closely by labor and business groups alike.

“Given numerous uncertainties, I am not able to speculate at this time about what might happen as a result of tomorrow’s meeting and scheduled vote,” NLRB spokeswoman Nancy Cleeland said. “We will all have to wait and see.”

The union election proposal has sparked an outcry from business groups, which argue it would leave companies little time to inform their workers about unionization. Republicans have said the rule could let workers hold a union vote only 10 days after filing a petition. 

NLRB Chairman Mark Pearce, a Democrat, said the labor board would not vote Wednesday on the parts of the rule that would speed up the elections and share workers’ contact information with unions, among other changes. Instead, it will consider only portions that deal with what the board calls “needless litigation” over proposed union votes.

“Because the board may lose a quorum in a matter of months, I am putting forward a more limited resolution at this time,” Pearce said in a news release. “Other portions of the original rule will remain under consideration by the board for possible future action.”

Former NLRB officials reached for comment by The Hill said Hayes’s non-participation would be unprecedented, and disagreed about what effect it might have on the process. Some said Hayes can single-handedly stop the union regulation, while others argued that the board can hold the vote without him.

“The answer is unclear,” said John Irving, who worked at the NLRB for more than 13 years, including as general counsel. “I can’t ever remember this happening as applied in a rulemaking context. It’s probably safe to say this has never happened in a rulemaking context.”

If the resolution is approved Wednesday, the NLRB will then draft a final rule and have another vote to approve it.

NLRB member Craig Becker’s recess appointment will end once Congress adjourns for the year. That would bring the labor board down to two members and deny it a quorum. 

“This is uncharted territory for the board when it comes to rulemakings,” said John Toner, a former executive secretary for the NLRB. 

Toner, now senior counsel at Seyfarth Shaw, said there is a case to be made that the NLRB would not need Hayes’s participation to sign off on the new rule.

“I think there is an argument that the failure of the third member to participate in a rulemaking would not necessarily invalidate the rulemaking,” Toner said.

Peter Schaumber, a former NLRB chairman and a Republican, however, was adamant that Hayes would have to participate if the labor board was to move forward.

“It is not unusual for a member to withhold a vote until a written majority decision circulates, to see the words and the reasoning,” Schaumber said.

If Hayes doesn’t vote or if he’s not given the chance to write a dissent, “the board cannot issue a final rule without violating its own written rule of procedure, and it will render the board’s deliberative process a charade,” Schaumber said. 

Other former NLRB members disagreed.

“Internal rules don’t trump the statute,” said Marshall Babson, a former Democratic member of the labor board. “The board derives its power from the statute.”

Babson, now a partner at Seyfarth Shaw, was counsel to the U.S. Chamber of Commerce for a 2010 Supreme Court case that ruled that the NLRB needs at least three of its five seats filled to act. Babson said questions were raised several times by the court about a member absenting himself from a three-member board and whether that would block action.

“My recollection is that every justice agreed that they would not have the power to disable the board,” Babson said.

Conservative activists have pressured Hayes to resign to stop the union election rule, and there is a movement afoot on Capitol Hill to stop it through legislation.

Rep. John Kline (R-Minn.), chairman of the House Education and the Workforce Committee, has offered legislation to stop the rule. The House is expected to vote on it Wednesday.