MO SB1677

Creates "Calvin's Law" (Section 302.023) prohibiting children under 10 years old from riding as passengers on motorcycles or motortricycles unless the vehicle has a proper passenger seat and the child can place both feet on passenger foot pegs, with exceptions for licensed physician medical exemptions

Requires all motorcycle/motortricycle passengers under 10 years old to wear protective headgear meeting state standards

Increases helmet violation fines from $25 to $100 when the violation involves a child passenger under 10 years old

Authorizes law enforcement to stop, inspect, or detain persons solely to determine compliance with child passenger requirements, creating an exception to the general prohibition on helmet-only stops

Effective date: January 1, 2027