Mich. Comp. Laws § 431.308a

Sec. 8a. (1) If the racing commissioner determines that all of the requirements of this act for issuing a race meeting license are met, the racing commissioner shall issue a race meeting license to the holder of a casino license issued under section 6 of the Michigan Gaming Control and Revenue Act, 1996 IL 1, MCL 432.206. (2) The holder of a race meeting license issued under this section shall not conduct pari-mutuel wagering at a licensed racetrack that is within 50 miles of another licensed racetrack at which 1 or more race meeting licensees may conduct pari-mutuel wagering.