MADISON, Wis. (AP) — The Wisconsin Democratic Party filed a lawsuit Thursday claiming a lame-duck law Republicans passed to limit Gov. Tony Evers’ powers is meant to retaliate against his supporters in violation of the U.S. Constitution.

The party filed the lawsuit in federal court in Madison. The action is the fourth legal challenge to the lame-duck measure since former Republican Gov. Scott Walker signed it into law in December, including a union lawsuit that Evers joined.

“(The law) was bald-faced undermining of the incoming administration,” the Democratic Party’s chairwoman, Martha Laning, told reporters on a conference call. “The will of the people is the law of the land and it’s about time Republicans start respecting that.”

Assembly Republican Speaker Robin Vos said during a luncheon in Madison that he wasn’t surprised Democrats were filing another lawsuit challenging the law.

Republican lawmakers passed the law in a messy all-night session in December. The measure prohibts Evers from ordering Democratic Attorney General Josh Kaul to withdraw Wisconsin from lawsuits without legislative permission, a move designed to ensure Evers can’t yank the state out of a multistate lawsuit challenging the Affordable Care Act.

The law also prohibits Kaul from settling lawsuits without legislative approval and shifts money won in settlements from Kaul’s office to the state’s general fund. It also allows legislators to intervene in cases using their own attorneys, unshackling GOP lawmakers from any Kaul stances they don’t approve.

Other provisions limit the window for early in-person voting and require state agencies to take down publications explaining state law by July unless they send all the documents through a new process that includes a public comment period.

The new lawsuit names Democratic campaign workers as well as a voter who supported Evers and Kaul as plaintiffs. The filing names as defendants a host of GOP lawmakers, including Vos and Senate Majority Leader Scott Fitzgerald, as well Evers and Kaul.

The lawsuit alleges the lame-duck law violates the U.S. Constitution’s free speech and equal protection guarantees. The statutes amount to retaliation against the Democratic workers and voters for their political viewpoint, eliminating their ability to enact policies they support through Evers and Kaul and diluting their votes, the filing argues.

Five labor unions, including the Service Employees International Union, and a group of liberal-leaning organizations led by the League of Women Voters filed separate lawsuits challenging the law in state court last month.