The Supreme Court ruled in favor of Starbucks on Thursday in a challenge against a labor ruling by a federal judge, making it more difficult for a key federal agency to intervene when a company is accused of illegally suppressing labor organizing.

Eight justices backed the majority opinion, which was written by Justice Clarence Thomas. Justice Ketanji Brown Jackson wrote a separate opinion concurring with parts of the majority opinion, dissenting from other portions and agreeing with the overall judgment.

The ruling came in a case brought by Starbucks over the firing of seven workers in Memphis who were trying to unionize a store in 2022. The company said it had fired them for allowing a television crew into a closed store, while the workers said that they were fired for their unionization efforts and that the company didn’t typically enforce the rules they were accused of violating.

After the firings, the National Labor Relations Board issued a complaint saying that Starbucks had acted because the workers had “joined or assisted the union and engaged in concerted activities, and to discourage employees from engaging in these activities.” Separately, lawyers for the board asked a federal judge in Tennessee for an injunction reinstating the workers, and the judge issued the order in August 2022.

The agency asks judges to reinstate workers in such cases because resolving the underlying legal issues can take years, during which time other workers may become discouraged from organizing even if the fired workers ultimately prevail.

In its petition to the Supreme Court, the company argued that federal courts had differing standards when deciding whether to grant injunctions that reinstate workers, which the N.L.R.B. has the authority to seek under the National Labor Relations Act.