The regional director of the National Labor Relations Board has blocked a vote to decertify the United Mine Workers of America at Alabama’s Warrior Met Coal.

Region 10 Director Lisa Henderson issued a 16-page ruling Thursday, stating that “the pending unfair labor practices tainted the atmosphere in which the employees signed the decertification petition…”

An election to decertify a union in a workplace can be held after collecting signatures from at least 30% of workers in a unit. A majority of votes in an election decides the outcome. The NLRB lists 795 employees affected in the Warrior Met Coal case.

A petition to decertify the union was filed with the NLRB back in April. The petition came a month after union members at Warrior Met Coal began returning to work after a 23-month strike, believed to be the longest in Alabama history.

The union offered an unconditional return to work in February after months of stalemate in the labor talks.

In Henderson’s decision, she wrote that it “stands to reason that striking employees would not be pleased with the Union when, after a prolonged strike, they returned to work without a collective-bargaining agreement.” However, some of that dissatisfaction came from “unfair labor practices” by Warrior Met.

The company’s “failure and refusal to provide requested information to the Union had a negative impact on the Union’s ability to effectively negotiate on behalf of the bargaining unit, which contributed to employee disaffection,” the decision states.

In June, National Labor Relations Board Judge Melissa Oliverio ruled Warrior Met Coal engaged in unfair labor practices by not providing the United Mine Workers of America with requested information during collective bargaining talks.

Attempts to contact Warrior Met Coal for comment were not immediately successful.

“They violated the law before the strike began, continue to violate the law today, and intend to keep violating it in the future,” International UMWA President Cecil E. Roberts said, in a statement.

“Our members have been fighting for fair treatment and respect from Warrior Met Coal, and the company’s unfair labor practices have caused significant harm to our members and their families. Ironically, it was a non-member who initiated the decertification petition in an attempt to deny every worker’s right to belong to a union in the workplace. The UMWA will continue to fight for justice and fairness for our members.”

“The ruling sends a clear message that they cannot violate workers’ rights with impunity,” Roberts said.