Mich. Comp. Laws § 791.229
Except as otherwise provided by law, all records and reports of investigations made by a probation officer, and all case histories of probationers shall be privileged or confidential communications not open to public inspection. Judges and probation officers shall have access to the records, reports, and case histories. The probation officer, the assistant director of probation, or the assistant director's representative shall permit the attorney general, the auditor general, and law enforcement agencies to have access to the records, reports, and case histories and shall permit designated representatives of a private contractor that operates a facility or institution that houses prisoners under the jurisdiction of the department to have access to the records, reports, and case histories pertaining to prisoners assigned to that facility. The relation of confidence between the probation officer and probationer or defendant under investigation shall remain inviolate.
MCL 791.229