Mich. Comp. Laws § 123.921
That whenever the legislative body of any county or township within the state of Michigan and the legislative body of any village or city situated in such county or township shall deem it expedient and for the public convenience and welfare that the offices of the city or village and county or township can be best maintained in the same building and when such legislative bodies shall have so declared by resolution, appearing upon the minutes of said bodies, it shall be lawful for such city or village and county or township and they are hereby authorized and empowered to contract to and with each other, through their proper representatives, for the joint acquiring and maintaining of a building or the acquiring of a site or sites and the erection, construction and maintenance of a building erected for and dedicated to public uses.
MCL 123.921