The case was filed by the Abbotsford Education Association, a local teachers union, according to the court. The justices agreed to take up the matter in a 5-1 decision, with Justice Annette Kingsland Ziegler dissenting. Justice Brian K. Hagedorn did not participate in the decision.

The court's order did not detail the specific legal arguments the union is raising, and it was not immediately clear when oral arguments would be scheduled.

Act 10 was signed into law in 2011 by then-Gov. Scott Walker, a Republican. The measure sharply limited public-sector unions' ability to bargain over wages, benefits and working conditions, and it required most public workers to contribute more toward their pensions and health insurance.

Walker has defended the law as a fiscal success, saying it cut costs across the state and gave local governments and school districts more control over their budgets.

The law's passage triggered massive protests at the State Capitol in Madison, drawing tens of thousands of demonstrators. Democratic lawmakers fled the state in an effort to block a vote, but the Republican-controlled Legislature ultimately approved the measure.

For more than a decade, Act 10 has been a defining fault line in Wisconsin politics, credited by supporters with stabilizing local budgets and blamed by critics for weakening unions and driving down wages and benefits for public workers. The case now before the Supreme Court could reopen that fight, with implications for school districts, municipal governments and the hundreds of thousands of public employees across the state.

The Abbotsford Education Association is a local affiliate representing educators in the Abbotsford School District in central Wisconsin. A ruling in its favor could restore bargaining rights for public workers or reshape how Act 10 is applied, while a decision upholding the law would cement one of the most consequential labor policies in modern Wisconsin history.