Mich. Comp. Laws § 123.1425: Prohibited licensing requirements by local government; limitation on enforcement.

Sec. 5.

(1) Beginning January 1, 2018, a political subdivision shall not impose any licensing requirements on any individuals who perform a specific occupation if the political subdivision does not already impose licensing requirements on that occupation. However, a political subdivision may continue to regulate any occupation that is subject to licensing requirements in that political subdivision before January 1, 2018.

(2) If an occupation is subject to licensing requirements imposed by the department of licensing and regulatory affairs or any other licensing authority of this state, a political subdivision of this state shall not impose any regulations on that occupation that add additional licensing requirements to those already imposed by the licensing authority of this state.

(3) Beginning January 1, 2018, if the department of licensing and regulatory affairs or any other licensing authority of this state imposes any new licensing requirements on any occupation that was previously unregulated by the state, and if the political subdivision has licensing requirements that regulate that occupation in effect at the time the new state licensing requirements take effect, the political subdivision may not continue to enforce its licensing requirements for that occupation on or after the date when the state licensing requirements take effect.