Mich. Comp. Laws § 730.509

Sec. 9. All files, records and dockets belonging to or appertaining to the office of the justices of the peace in office in any city affected by the provisions of this act shall be filed and safely kept in the office of the clerk of the municipal court of such city, and such files, records and dockets shall in all respects and for all purposes constitute records of the municipal court of such city.