Michigan Compiled Laws, Chapter 38. Civil Service and Retirement § 38.1103

Sec. 3. (1) Any municipal unit, which covers its employees under a retirement system or systems, by a majority vote of its governing body may elect to adopt the provisions of this act for its employees covered under such retirement system or systems.

(2) Any state unit, by a majority vote of its governing body, may elect to have the provisions of this act made applicable to its members.

(3) The governing body of a municipal or state unit, within 10 days after it elects to come under the provisions of this act, shall file written certification of its action with the secretary of state. Upon the filing of the certification the municipal unit or state unit shall be a reciprocal unit. The secretary of state shall maintain a list of reciprocal units, which list shall be available to any municipal unit or state unit requesting a copy.

(4) The provisions of this act, when adopted by a municipal or state unit shall be effective for the unit in addition to the provisions of charter, ordinance, resolution or state law governing the retirement systems for the reciprocal unit, as the provisions of charter, ordinance, resolution or state act are in force and as amended.