Mich. Comp. Laws § 750.497
Detouring traffic as public safety measure-Whenever in the opinion of the state highway commissioner a condition arises or is about to arise upon any of the highways of the state occasioned by the condition of said highway or by any approaching public gathering likely to bring unusual congestion of traffic thereon, and the public safety of persons using or about to use said highway is put in jeopardy, the state highway commissioner is hereby authorized by an appropriate order, to detour the traffic from or upon, provide the direction for any or all traffic, close to any or all traffic, or limit the traffic on said highway to certain classes of vehicles, under such conditions as he may in such order provide on any of the highways of the state of Michigan for such length of time as he may deem necessary.
Whenever the state highway commissioner shall make any order in any way regulating or closing traffic on any highways of this state under the authority of this section, he shall cause to be posted upon said highway in conspicuous places at each terminal of the restricted or closed highway, conspicuous notices of such regulations or closing order.
Any person violating any of the provisions of said order, or using said highway in any manner prohibited in said order after and during the time that notices of said order shall be properly posted as herein provided, shall be deemed guilty of a misdemeanor, and upon conviction thereof shall be punished by a fine of not more than 10 dollars or by imprisonment in the county jail for not more than 10 days, or by both such fine and imprisonment in the discretion of the court.
MCL 750.497