Michigan Compiled Laws, Chapter 730. Justice Courts and Municipal Courts § 730.501

Sec. 1. (1) In any city in this state now or hereafter having a population of 15,000 or more, according to the latest or each succeeding federal decennial census, having a justice court with 1 or more justices of the peace who are paid a salary in lieu of fees, whether said justices and justice courts are provided for by city charters or by any statutes of this state, such courts shall hereafter be designated as municipal courts and the justices thereof as municipal judges; said change shall in no way affect or change the present laws and statutes of this state, except that the word “municipal” shall replace “justice” with full force and effect and with like intent whenever and wherever the said word “justice” appears in said acts or general or special laws of the state or the municipal charter of any such city with reference to justice courts or justices of the peace.

(2) Any city having a population of less than 15,000 and a justice of the peace who is paid a salary in lieu of fees and required to be an attorney may adopt by ordinance the provisions of this act and such court shall be deemed a municipal court under this act for all purposes while said ordinance is in effect.

(3) Any city may provide in its charter, whether in the first instance or by amendment or revision, for a municipal court under the provisions of this act. If any city provides in its charter for a municipal court to come into being at the end of the term or terms of its incumbent justices of the peace, it shall provide that each municipal judge, including the first incumbent, shall be an attorney at law as required in section 8 of this act.  1