Mich. Comp. Laws § 418.657

Sec. 657. Incorporated public boards and commissions shall treat the cost of benefits payable pursuant to the provisions of this act or the cost of insuring their liability for such benefits as part of their necessary operating expense and such sums shall be separately budgeted in any requisition authorized by law to be made on any other public corporation, body or officer. If the incorporated public board or commission is authorized by law to require the levying of taxes through any other public corporation or officer for its use, the expense, separately itemized, may be made a part of the tax levy.