Mich. Comp. Laws § 767.6a
On termination of any such inquiry lasting not more than 30 calendar days the docket, journal, reporters' notes, transcript and other record of such judge in such inquiry shall be sealed and filed with the clerk of the court having jurisdiction; and if lasting more than 30 calendar days shall be sealed and filed with the clerk of the supreme court of the state of Michigan, where it shall be held secretly in a separate container securely locked. Any person who shall violate the secrecy herein ordered as to such docket, journal, transcript and record shall be punished as provided in section 4 hereof. And the entire transcript and record as to any witness, and so far as material, including any grant of immunity, shall be available to such witness in connection with any appeal or other judicial proceeding where it may be relevant upon such witness filing a petition with the circuit court of the county in which he resides setting forth the proceeding for which such documents are sought and describing the portions of such transcript and record as to such witness only, which such witness requested for such appeal or proceeding; the judge of such circuit court shall issue an order upon the filing of such petition directed to the clerk of the supreme court of the state of Michigan or the clerk of the court, as the case may be, ordering such clerk to make available to such witness all such portions of the transcript and record as shall pertain to such witness and as set forth in the petition. The clerk shall immediately reseal the remaining transcript and records after compliance with such order. The petitioner shall execute to the clerk of the supreme court a receipt for such documents and such documents shall be returned to the clerk immediately upon the termination of such appeal or proceeding for which the same shall have been obtained: Provided, however, upon the petition of the prosecuting attorney of the county in which such inquiry was conducted, or any other interested person, any circuit judge, acting as such in said county, upon determining that there is no further need for preserving and retaining the same, shall enter an order providing for the referring to the supreme court, for the entry of such order or orders as a majority of the court may at any time determine, for the destruction of said transcripts, notes and records, or any part thereof: Provided further, That no such order shall be entered by such circuit judge until at least 6 years after the termination of such inquiry.
MCL 767.6a