Mich. Comp. Laws § 32.801

Sec. 401. Except in time of war or national emergency declared by the congress of the United States, officers, warrant officers and enlisted personnel shall be retired at the highest rank they have held, from active service with the national guard prior to/or upon reaching age 62, and their names shall be placed on the state military retired list. Officers, warrant officers and enlisted personnel of the defense force serving this state during an emergency or war are eligible for retirement and enrollment on the state military retired list under the same conditions as apply to officers, warrant officers and enlisted personnel of the national guard.