The tax will begin on January 1, 2026, and it’s estimated it will generate $420 million annually to help fund road improvements as part of the state budget. The lawsuit, filed in the Mcihigan Court of Claims, argues that the tax violates constitutional requirements for changing voter-initiated laws. Michigan voters legalized recreational marijuana in 2018, and the suit contends that any changes to voter – approved laws require either a three-fourths legislative vote or voter approval. The lawsuit asks the court to strike down the new tax.