A case pending before the National Labor Relations Board could have major effects on unionization efforts, with the board’s general counsel, Jennifer Abruzzo, pushing to reinstate a long-defunct doctrine that would make unionization much easier for employees.

As part of President Biden’s promise to be the most pro-union president in history, one of his administration officials, Ms. Abruzzo, is fighting to overturn 50 years of established precedent in American labor law and reinstate a rule that would allow unions to organize at a company without an election.

Ms. Abruzzo is arguing for the revival of what is known as the “Joy Silk” doctrine, which was the precedent for unionization efforts between 1949 and 1969. Under the doctrine, employers can be required to recognize a union through a system called a card check, which is when a majority of employees sign a card indicating they want to join a union.

Without the Joy Silk requirement, employers can refuse to acknowledge the fact that a majority of employees signed cards and force the union to seek an NLRB-certified election, which requires secret ballots.

Critics of the card check process, like the National Association of Manufacturers, contend that it is “more susceptible to fraud and coercion” because it is apparent which employees say they want to form a union, in contrast with a secret ballot election.

The issue has arisen out of a dispute between Cemex Construction Materials Pacific and the International Brotherhood of Teamsters, originally raised in 2019, and heard by an administrative court at San Francisco in 2021.

The court ruled that Cemex had violated a number of provisions of the National Labor Relations Act in its attempts to prevent employees from unionizing.

The case, however, was transferred to the NLRB at Washington, D.C., in 2021. In April of 2022, Ms. Abruzzo filed a brief arguing for a return to the long-abandoned Joy Silk Doctrine. Now, union organizers and companies alike await a decision that could come any day.

The name Joy Silk comes from a 1949 dispute between Joy Silk Mills, Inc. and the United Textile Workers of America. In it, the NLRB ruled that employees could unionize by card check — meaning a majority of the relevant bargaining unit has already joined the union.

In order to prevent card check unionization under the Joy Silk doctrine, the employer had to prove they had a “good faith doubt” of the union’s majority status to force a secret ballot election, a high bar to clear.

In 1969, the NLRB abandoned the Joy Silk standard, putting forward a new position in the Supreme Court case National Labor Relations Board v. Gissel Packing Company, Inc.

In that case, the NLRB’s associate general counsel, Dominick Manoli, stated that the board would not issue a complaint if an employer refused to acknowledge a card check unionization effort.

This created a new standard, which essentially allowed employers to refuse to acknowledge a card check for any reason and demand a NLRB-certified secret ballot election, a lengthy process that can allow companies to deploy anti-unionization efforts or persuade employees not to vote for the union.

Under current policy, the NLRB will only issue a bargaining order if it can be proved that an employer engages in “extensive unfair labor practices” that make a “fair election highly unlikely or impossible.”

Ms. Abruzzo, however, argues that the current standard is insufficient because the NLRB has failed to “deter unfair labor practices during union organizing drives and provide for free and fair elections.”

“Joy Silk is logically superior to current Board law’s ability to deter election interference,” Ms. Abruzzo argues in a brief. “It directly disincentivizes an employer from engaging in unfair labor practices during organizing campaigns to avoid a bargaining obligation, as doing so will typically result in the imposition of a bargaining order.”

She provides examples of things like “captive audience” meetings where employees are forced to attend mandatory meetings where employers deploy anti-union messaging under what Ms. Abruzzo calls “an unlawful threat that employees will be disciplined or suffer other reprisals if they exercise their protected right not to listen to such speech.”

Cemex’s response to Ms. Abruzzo’s brief does not address her arguments for the reinstatement of Joy Silk. Others, however, have expressed concern that a return to Joy Silk would give employees the upper hand over employers in unionization efforts.

Attorneys Robert Brody and Luis Torres of Brody and Associates, a law firm that provides services aimed at ending unionization efforts to employers, argue that reverting to the Joy Silk rule would allow unions to be formed without a vote.

“Employers will be forced to recognize the union and begin bargaining without ever letting their employees vote for or against the union,” the pair argue in a brief filed with the NLRB.

“The Joy Silk doctrine would drastically alter 21st-century unionization efforts, enabling unions to bypass union elections in nearly all cases,” Messrs. Brody and Torres write.

Any decision from the NLRB would also likely have to withstand an appeal to the Court of Appeals for the District of Columbia Circuit and potentially also the Supreme Court.