Mich. Comp. Laws § 41.813

Sec. 13. By a majority vote of the township board at a regular or a special meeting called for that purpose, a township board may provide for the employment of 1 or more traffic officers in the township. The compensation of the officer or officers shall be paid from the general fund of the township. By a majority vote of all the township boards, 2 or more townships may appoint a traffic officer at a joint meeting of these township boards held for that purpose, and the proportion of the compensation of the traffic officer or officers to be paid by each of the townships shall be determined at this joint meeting.