Michigan Compiled Laws, Chapter 500. Insurance Code of 1956 § 500.2020

Sec. 2020.  The following are defined as unfair methods of competition and unfair and deceptive acts or practices in the business of insurance:

Making or permitting any unfair discrimination between individuals of the same class and of essentially the same hazard in the amount of premium, membership, or policy fees, or rates charged for any policy or contract of accident or health insurance applicable to individual or family expense coverage or in the benefits payable thereunder, or in any of the terms or conditions of such contract, or in any other manner whatever.