A driver wants to carry a 16-year-old friend in the open bed of a small pickup (licensed under 12,000 pounds) on a state highway, for an ordinary trip. What does Missouri law say?

Correct answer: It is not allowed for riders under 18, apart from a few listed cases

Why

An open truck bed has no seats, belts or walls to hold a rider, so a sudden stop, swerve or crash can throw the person onto the road. For that reason RSMo 304.665 keeps riders under 18 out of the open bed of smaller trucks on state and federal highways and within city limits, except in listed cases. The Missouri Driver Guide does not state this rule, but it asks drivers to make sure every passenger uses a seat belt or child restraint.

Verified against Missouri Driver Guide · Use Seat Belts and Child Restraints · p. 57