Mich. Comp. Laws § 207.3
Said board shall have access to all books, papers, documents, statements and accounts, on file or of record in any of the departments of state, subject to the rules and regulations of the respective departments relative to the care of public records. It shall have like access to all books, papers, documents, statements and accounts, on file or of record in counties, townships and municipalities. It shall have the right to subpoena witnesses, upon a subpoena signed by the chairman of said board and attested by the secretary thereof, delivered to such witnesses, which subpoenas may be served by any person authorized to serve subpoenas from courts of record in this state, and the attendance of witnesses may be compelled by attachment, to be issued by any circuit court in this state, upon proper showing that such witness has been properly subpoenaed, and has refused to obey such subpoena. The person appearing in response to such subpoena shall receive like compensation as is allowed by the statutes of this state to witnesses in the circuit court, to be allowed by the board of state auditors upon the presentation of a copy of such subpoena, with the number of days' service and mileage endorsed thereon and approved by a member of said board of assessors, or the secretary thereof. The person serving such subpoena shall receive the same compensation now allowed to sheriffs or other officers for serving subpoenas. Said board shall have power to examine witnesses under oath, said oath to be administered by any member of the board, or by the secretary thereof. It shall have the right to inspect and examine the books, papers or accounts of any corporation, firm or individual owning property to be assessed by said board, and if such corporation, firm or individual refuse to permit said inspection and examination, or neglect or fail to appear before said board in response to its subpoena, said corporation, firm or individual shall, for each such refusal, neglect or failure, forfeit the sum of 500 dollars to the state, the sum so forfeited to be recovered in a proper action brought in the name of the people of the state of Michigan, in any court of competent jurisdiction.
MCL 207.3