MONTGOMERY, Ala. — Amazon workers in Alabama will decide for a third time in three years whether to unionize after a federal judge ruled that the retail giant improperly influenced the most recent vote in which employees rejected a union.

Administrative law judge Michael Silverstein on Tuesday ordered the third vote for Amazon warehouse workers in Bessemer, Alabama, about 20 miles south of Birmingham, after determining that Amazon committed six violations leading up to the second election in March 2022.

Amazon managers surveilled employees’ union activities and threatened workers that the plant would be closed if they voted with the union, Silverstein said in an 87-page decision. Amazon managers also removed pro-union materials from areas where anti-union materials were available, the judge determined.

The National Labor Relations Board also found improper interference in the first election in 2021, leading to the redo in 2022.

Silverstein’s decision comes after months of testimony and is the latest development in a nationwide legal battle involving Amazon, the National Labor Relations Board and unions spearheading unionization efforts. Some states, like California, have fined the mega retailer for labor violations.

Both Amazon and the union that organized the vote in Bessemer said that they would appeal the judge’s order.

The president of the Retail, Wholesale and Department Store Union, Stuart Appelbaum, affirmed the court’s findings that Amazon broke labor laws.

But he also said that he believed Amazon was likely to commit similar violations in a third election if the court did not order “significant and meaningful remedies” to protect the vote.

Specifically, the union requested access to private meetings between Amazon representatives and workers, as well as training for Amazon supervisors on labor laws. The judge declined those requests.

The Bessemer facility has approximately 6,000 employees.