Missouri Revised Statutes Title XIX. Motor Vehicles, Watercraft and Aviation § 304.665. Riding in open bed of truck prohibited, when, exceptions, penalty

(1) An employee engaged in the necessary discharge of the employee's duties where it is necessary to ride in the unenclosed bed of the truck;

(2) Any person while engaged in agricultural activities where it is necessary to ride in the unenclosed bed of the truck;

(3) Any person riding in the unenclosed bed of a truck while such truck is being operated in a parade, caravan or exhibition which is authorized by law;

(4) Any person riding in the unenclosed bed of a truck if such truck has installed a means of preventing such person from being discharged or such person is secured to the truck in a manner which will prevent the person from being thrown, falling or jumping from the truck;

(5) Any person riding in the unenclosed bed of a truck if such truck is being operated solely for the purposes of participating in a special event and it is necessary that the person ride in such unenclosed bed due to a lack of available seating.“Special event”, for the purposes of this section, is a specific social activity of a definable duration which is participated in by the person riding in the unenclosed bed;

(6) Any person riding in the unenclosed bed of a truck if such truck is being operated solely for the purposes of providing assistance to, or ensuring the safety of, other persons engaged in a recreational activity; or

(7) Any person riding in the unenclosed bed of a truck if such truck is the only legally titled, licensed and insured vehicle owned by the family of the person riding in the unenclosed bed and there is insufficient room in the passenger cab of the truck to accommodate all passengers in such truck. For the purposes of this subdivision the term “family” shall mean any persons related within the first degree of consanguinity.