Mich. Comp. Laws § 767A.3

Sec. 3. (1) A judge may authorize a prosecuting attorney in writing to issue 1 or more investigative subpoenas under this chapter if all of the following circumstances exist: (a) A petition is properly filed under section 2. (b) The judge determines there is reasonable cause to believe a felony has been committed. (c) The judge determines there is reasonable cause to believe that either of the following circumstances exists: (i) The person who is the subject of the investigative subpoena may have knowledge regarding the commission of the felony. (ii) The records, documents, or physical evidence are relevant to investigate the commission of a felony described in the petition. (2) An order issued by the judge authorizing a prosecuting attorney to issue 1 or more investigative subpoenas under this chapter shall contain all of the following: (a) A statement identifying each felony to be investigated. (b) A statement listing each person to whom an investigative subpoena may be issued. (c) A statement listing the records, documents, or physical evidence subject to production under an investigative subpoena. The statement shall describe the records, documents, or physical evidence with sufficient definiteness to permit those records, documents, or physical evidence to be fairly identified. (3) A prosecuting attorney may issue investigative subpoenas to the extent authorized by the judge in the authorization order. (4) If additional investigative subpoenas are required to conduct the investigation, the prosecuting attorney may file 1 or more supplemental petitions with the judge who issued the authorization to conduct the investigation requesting those additional investigative subpoenas. A supplemental petition under this subsection may incorporate the original petition for an investigative subpoena by reference. The petition shall be filed in the same manner that an original petition is filed under section 2.