Michigan Compiled Laws, Chapter 333. Health § 333.20924

Sec. 20924. (1) Except as provided in subsection (2), a person shall not furnish, operate, conduct, maintain, advertise, or otherwise be engaged or profess to be engaged in the business or service of the transportation of patients in this state unless the person uses an ambulance licensed under this part.

(2) An ambulance operated by an agency of the United States is not required to be licensed under this part. This part does not apply to an ambulance or ambulance personnel from another state or nation or a political subdivision of another state or nation that is performing in this state emergency assistance required by an official of this state.