A unanimous Wisconsin Supreme Court on Tuesday sided with the Democratic state attorney general in a long-running battle over a law passed by Republicans who wanted to weaken the attorney general’s power during a lame-duck legislative session in 2018.

In a 7-0 ruling, the court found the law unconstitutionally violated the separation of powers doctrine. The court decided:

Litigation on behalf of the state is chiefly a core executive function. But where the Legislature has an institutional interest
rooted in the constitution, such cases may fall within the borderlands of shared powers … As the Legislature has failed to demonstrate that these types of cases implicate an institutional interest granting the Legislature a seat at the table, the
powers at issue are core executive powers.

Wisconsin Attorney General Josh Kaul released the following statement after the decision was announced: “As a result [of the ruling], the Wisconsin Department of Justice will be able to more efficiently resolve the cases that are impacted by this decision, including civil actions enforcing our consumer protection laws and civil actions enforcing our environmental protection laws.”

In 2018, before a new governor and attorney general assumed office, the Wisconsin legislature amended the statute governing the Department of Justice’s (DOJ) ability to settle cases. The new amendment led to the DOJ not being able to settle civil cases unless and until a legislative committee approved the DOJ’s settlement plan.

Wisconsin Attorney General Josh Kaul, the DOJ, Governor Tony Evers, and the secretary of the Department of Administration filed suit in the Dane County Circuit Court.