Mich. Comp. Laws § 257.71: “Traffic control order” defined.

Sec. 71.

"Traffic control order" means an order officially establishing the location of traffic control devices and traffic control signals on the highways of this state by the authority having jurisdiction over such highway and filed with the county clerk of the county traversed by such highway. A certified copy thereof shall be prima facie evidence in all courts of the issuance of such order.