Mich. Comp. Laws § 400.108

Sec. 108. A medically indigent person as defined under section 106(1)(a) is entitled to all the services enumerated in section 109. A medically indigent person as defined under section 106(1)(b) is entitled to medical services enumerated in section 109(1)(a), (c), and (e). He or she is entitled to the services enumerated in section 109(1)(b), (d), and (f) to the extent of appropriations made available by the legislature for the fiscal year. Medical services shall be rendered upon certification by the attending licensed physician and dental services shall be rendered upon certification of the attending licensed dentist that a service is required for the treatment of an individual. The services of a medical institution shall be rendered only after referral by a licensed physician or dentist and certification by him or her that the services of the medical institution are required for the medical or dental treatment of the individual, except that referral is not necessary in case of an emergency. Periodic recertification that medical treatment that extends over a period of time is required in accordance with regulations of the department of community health is a condition of continuing eligibility to receive medical assistance. To comply with federal statutes governing medicaid, the department of community health shall provide early and periodic screening, diagnostic and treatment services to eligible children as it considers necessary.