Mich. Comp. Laws § 767.7c

Sec. 7c. The court of appeals of this state, acting in a 3-judge panel consistent with the Michigan court rules, may convene a grand jury with jurisdiction over 2 or more counties in this state as follows: (a) If a petition is filed under section 7b(1) by the attorney general, the court of appeals may convene a grand jury with jurisdiction over 2 or more of the counties named in the petition. (b) If a petition is filed under section 7b(2) by 2 or more attorneys who are county prosecuting attorneys in this state, the court of appeals may convene a grand jury with jurisdiction over 2 or more of the counties named in the petition in which the attorneys are prosecuting attorneys.