Crimes: controlled substances; production and sale of kratom; prohibit. Amends 1931 PA 328 (MCL 750.1 - 750.568) by adding sec. 473a.

HB 5537 prohibits the production, sale, or offering for sale of kratom (including all parts of the Mitragyna speciose plant and synthetic variants like 7-hydroxymitragynine) in Michigan. It directly affects businesses and individuals selling kratom products, imposing misdemeanor penalties that escalate based on severity: up to 90 days in jail and $5,000 fines for first offenses, with harsher penalties for repeat violations or sales to minors. Sales to anyone under 18 carry enhanced penalties, including up to one year in jail and $10,000 fines for first offenses. The law defines "kratom" broadly to cover all plant parts, extracts, and synthetic forms, making these activities illegal under Michigan's penal code.