Mich. Comp. Laws § 767.3
Whenever by reason of the filing of any complaint, which may be upon information and belief, or upon the application of the prosecuting attorney or attorney general, any judge of a court of law and of record shall have probable cause to suspect that any crime, offense or misdemeanor has been committed within his jurisdiction, and that any persons may be able to give any material evidence respecting such suspected crime, offense or misdemeanor, such judge in his discretion may make an order directing that an inquiry be made into the matters relating to such complaint, which order, or any amendment thereof, shall be specific to common intent of the scope of the inquiry to be conducted, and thereupon conduct such inquiry. In any court having more than 1 judge such order and the designation of the judge to conduct the inquiry shall be made in accordance with the rules of such court. Thereupon such judge shall require such persons to attend before him as witnesses and answer such questions as the judge may require concerning any violation of law about which they may be questioned within the scope of the order. The proceedings to summon such witness and to compel him to testify shall, as far as possible, be the same as proceedings to summon witnesses and compel their attendance and testimony. The witnesses shall not receive any compensation or remuneration other than witness fees as paid witnesses in other criminal proceedings. The witness shall not be employed in any capacity by the judge or by any person connected with such inquiry, within the scope of the inquiry being conducted. Whenever a subpoena is issued by the judge conducting the inquiry, commanding the appearance of a witness before the judge forthwith upon the service of such subpoena, and, following the service thereof, the witness arrives at the time and place stated in the subpoena, the judge issuing the same shall be forthwith notified of the appearance by the officer serving the subpoena, and the judge forthwith shall appear and take the testimony of the witness. Any person called before the grand jury shall at all times be entitled to legal counsel not involving delay and he may discuss fully with his counsel all matters relative to his part in the inquiry without being subject to a citation for contempt. The witness shall have the right to have counsel present in the room where the inquiry is held. All matters revealed to the attorney shall be subject to the requirements of secrecy in section 4, and any revelation thereof by the attorney shall make him subject to punishment as provided in section 4. No testimony shall be taken or given by any witness except in the presence of the judge.
Any judge, prosecuting attorney or special prosecuting attorney, or the attorney general participating in any inquiry under this section which continues more than 30 calendar days shall thereafter be disqualified from appointment or election to any office other than one held at the time of the inquiry. The disqualification shall not extend more than 1 year from date of termination of the inquiry, as determined by final order of the judge entered prior to such date.
MCL 767.3