Mich. Comp. Laws § 390.791

Sec. 1. Alumni associations or other organizations composed of graduates of any degree-granting educational institution within the state of Michigan and duly authorized to elect trustees or other members of the governing body of their respective institutions, may, and such associations or other organizations are hereby empowered to permit duly qualified members, not present at the time and place appointed for the election of such trustees, to cast their votes in writing under such rules and regulations for the reception, canvass and return of such votes as each such association or organization may adopt.