Missouri Revised Statutes Title XXXVIII. Crimes and Punishment; Peace Officers and Public Defenders § 569.155. Trespass of a school bus, penalty--schools to establish student behavior policy, when

1. A person commits the offense of trespass of a school bus if he or she knowingly and unlawfully enters any part of or unlawfully operates any school bus.

2. For the purposes of this section, the terms “unlawfully enters” and “unlawfully operates” refer to any entry or operation of a school bus which is not:

3. In order to preserve the public order, any district which adopts the policies described in subsection 2 of this section shall establish and enforce a student behavior policy for students on school buses.

4. The offense of trespass of a school bus is a class A misdemeanor.