Mich. Comp. Laws § 551.15: Ceremony performance with knowledge of lack of authority or legal impediment; penalty.

Sec. 15.

If any person shall undertake to join others in marriage, knowing that he is not lawfully authorized so to do, or knowing of any legal impediment to the proposed marriage, he shall be deemed guilty of a misdemeanor, and upon conviction thereof shall be punished by imprisonment in the county jail not more than 1 year, or by a fine not less than 50 nor more than 500 dollars, or by both such fine and imprisonment, in the discretion of the court.