A Michigan Court of Appeals has ruled a 2012 law that essentially required teachers and other public school workers to begin to contribute to their retirement plans was constitutional. The court upheld an earlier finding by the Court of Claims that allowed the controversial measure to stand. Under the law, teachers remaining in the basic retirement system would begin contributing 4 percent of their salary to their pension. Teachers could also move to a defined contribution plan or freeze current benefits and see a lower benefit multiplier in future years.