Mich. Comp. Laws § Article IX § 29: State financing of activities or services required of local government by state law.

Sec. 29.

The state is hereby prohibited from reducing the state financed proportion of the necessary costs of any existing activity or service required of units of Local Government by state law. A new activity or service or an increase in the level of any activity or service beyond that required by existing law shall not be required by the legislature or any state agency of units of Local Government, unless a state appropriation is made and disbursed to pay the unit of Local Government for any necessary increased costs. The provision of this section shall not apply to costs incurred pursuant to Article VI, Section 18.