Mich. Comp. Laws § 457.555

Sec. 5. Such grand court when properly incorporated shall have power to institute and charter subordinate courts within this state and from time to time make, alter or rescind such constitution, general laws or by-laws as the grand court shall judge proper for the government of such subordinate courts, not repugnant to the laws of the state: Provided, That the existing subordinate courts heretofore duly chartered by the grand court shall be subject to the grand court under this act, as heretofore, in the same manner and to the same extent: Provided further, That in case the incorporators shall by death, resignation or for other cause under the rules of the grand court, become ineligible to act in such capacity, their successors may from time to time be elected by the grand court.