Mich. Comp. Laws § 397.555

Sec. 5. To be eligible for membership in a cooperative library, a local library shall do all of the following: (a) Maintain a minimum local support of 3/10 of a mill on taxable value, as taxable value is calculated under section 27a of the general property tax act, 1893 PA 206, MCL 211.27a, in the fiscal year before October 1 of the year before distribution. (b) Participate in the development of cooperative library plans. (c) Loan materials to other libraries participating in the cooperative library. (d) Maintain an open door policy to the residents of the state, as provided by section 9 of article VIII of the state constitution of 1963.