Mo. Rev. Stat. § 300.325: When permits required for parades and processions.

No funeral, procession or parade containing two hundred or more persons or fifty or more vehicles except the forces of the United States Army or Navy, the military forces of this state and the forces of the police and fire departments, shall occupy, march or proceed along any street except in accordance with a permit issued by the chief of police and such other regulations as are set forth herein which may apply.