DETROIT (AP) — The Michigan Supreme Court says state workers can’t be forced to pay labor unions for negotiating contracts and providing other services.

In a 4-3 decision Wednesday, the court says the state Civil Service Commission lacks the authority to impose mandatory fees on thousands of civil servants.

It’s a big defeat for unions, especially the United Auto Workers, which have been collecting fees from state workers, even if workers didn’t want full membership.

Michigan has had a right-to-work law since 2013. It says public and private employees don’t have to pay union dues or fees as a condition of employment.

The Supreme Court, however, says its decision isn’t based on that law. The court says the ruling is based on the Civil Service Commission’s powers as described in the constitution.