Mo. Rev. Stat. § 198.061: Penalty for providing services without license — penalty for interfering with enforcement of law.

1. No person shall, jointly or severally, offer, advertise or hold out to the public, services subject to section 198.015 without a currently valid appropriate license issued by the department to render the particular services.

2. No person, jointly or severally, shall interfere with or prevent any duly authorized representative of the department or the attorney general from lawful enforcement of sections 198.003 to 198.186, 198.200, 202.905, 208.030, or 208.159.

3. Any person violating any provision of this section shall be guilty of a class C misdemeanor.