Mo. Rev. Stat. § 576.030: Obstructing government operations — penalty.

1. A person commits the offense of obstructing government operations if he or she purposely obstructs, impairs, hinders or perverts the performance of a governmental function by the use or threat of violence, force, or other physical interference or obstacle.

2. The offense of obstructing government operations is a class B misdemeanor. The offense of obstructing government operations is a class A misdemeanor if the person uses violence or force.