Michigan Compiled Laws, Chapters 475 to 479 Motor Carrier Act § 479.11

Sec. 11. (1) The commission may examine all records, books, accounts, and files of a motor carrier to whom a certificate has been issued under this act having to do with the business of transportation conducted by the motor carrier.If ordered by the commission, the motor carrier shall produce at any hearing or proceeding before the commission the records, books, accounts, and files or other data or information for use at the hearing or proceeding.A motor carrier shall preserve the records, books, accounts, and files for at least 3 years, except that a motor carrier shall preserve delivery receipts, delivery records, and bills of lading for at least 1 year. The commission may compel the attendance and testimony of witnesses and do all things necessary to carry out and enforce this act.

(2) Except as otherwise provided by law, a member of the commission, clerk, officer, or employee of this state shall not divulge or make known to any person the operations, style of work, or any other information regarding the operations of a motor carrier visited or inspected by him or her in the discharge of his or her official duties, or permit any report, books, documents, accounts, files, or other data examined or inspected by him or her to be seen or examined by any person. The information obtained under this section is inviolate, except for the purposes of carrying out the provisions of this act. It is the express legislative intent to permit the use of the information by the commission, but to prevent its publication in any manner, except when lawfully presented in open hearings either before the commission or a member of the commission, or before a court of law.This section does not apply to public files of the commission pertaining to the application for and the certificate of any motor carrier, or to quarterly or other reports, which shall be open to inspection during office hours by any motor carrier, shipper, or consignee.

(3) A person who violates this section is guilty of a misdemeanor.