Mich. Comp. Laws § 750.58: Horses; unhitching and driving away.

Sec. 58.

Unhitching and driving away horses without authority-Any person who shall wilfully and maliciously or wantonly, and without authority unhitch any horse or team belonging to another, and lawfully hitched or standing in any street, alley or other place, or who in like manner shall ride or drive such horse or team away shall be guilty of a misdemeanor.