(Bloomberg Law) -- Amazon.com Inc. violated federal labor law as part of its efforts to resist unionization at two facilities in New York City, a National Labor Relations Board judge ruled in a case that tees up major potential changes to board precedent.

Amazon illegally threatened to withhold wage increases and improved benefits if workers elected a union, Administrative Law Judge Benjamin Green held Monday. The company also broke the law by removing a worker’s post on a digital message board inviting his colleagues to sign a petition at a union tent to make Juneteenth a paid holiday, the judge found.

Green dismissed several other allegations that the NLRB general counsel’s office lodged against Amazon, including some that relied on arguments to change board precedent to find the company’s conduct illegal. Administrative law judges are required to apply existing case law.

With the case transferred to the NLRB to consider challenges to the judge’s ruling, the Democrat-majority board will get the opportunity to overturn longstanding pro-management precedent, including a 75-year-old decision allowing mandatory anti-union meetings convened by employers.

NLRB General Counsel Jennifer Abruzzo in an April 2022 memo publicly targeted those “captive audience meetings”—one of the most potent weapons in employers’ arsenals for beating back union campaigns. Such mandatory gatherings “inherently involve an unlawful threat that employees will be disciplined or suffer other reprisals if they exercise their protected right not to listen to such speech,” she said in the memo.

The case against Amazon arose from the Amazon Labor Union’s organizing drive at two facilities in Staten Island, N.Y. Workers at one of the plants elected the union as their bargaining agent last April, while workers at the second location across the street opted against union representation a month later.

In addition to outlawing captive audience meetings, the general counsel’s office in the Amazon case has advocated for changes to board law to narrow what employers can say about the consequences of unionization and broaden what company conduct can be considered unlawfully biased limitations on employee solicitation.

“We need a house cleaning of anti-union board decisions that have been around since the enactment of the Taft-Hartley Act” in 1947, said Amazon Labor Union’s lawyer, Seth Goldstein of Julien Mirer Singla & Goldstein PLLC.

Representatives for Amazon and the NLRB general counsel’s office couldn’t immediately comment.

The case is Amazon.com Services, Inc., N.L.R.B. A.L.J., Case 29-CA-280153, 1/30/23.

To contact the reporter on this story: Robert Iafolla in Washington at riafolla@bloomberglaw.com

To contact the editors responsible for this story: Rebekah Mintzer at rmintzer@bloombergindustry.com; Genevieve Douglas at gdouglas@bloomberglaw.com

(Updated with additional reporting throughout.)

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