Missouri Revised Statutes Title XIX. Motor Vehicles, Watercraft and Aviation § 302.705. Commercial motor vehicle operator, only one license--age requirements--notice to employer and director upon conviction for motor vehicle violation, when

1. No person who drives a commercial motor vehicle shall have more than one driver's license.

2. No person is eligible for a commercial driver's license who is under eighteen years of age, except any person transporting a hazardous material must be at least twenty-one years of age.

3. Any driver of a commercial motor vehicle holding a commercial driver's license issued by this state, and who is convicted of violating any state law or county or municipal ordinance regulating the operation of motor vehicles in any other state, other than parking violations, shall notify the director in writing on a form prescribed by the director within thirty days of the date of conviction. Upon notification of such conviction the director may apply the conviction information to the driver's record. If such conviction would result in disqualification of the license under sections 302.700 to 302.780, the director shall disqualify the license in accordance with sections 302.700 to 302.780.

4. Any driver of a commercial motor vehicle holding a commercial driver's license issued by this state, and who is convicted of violating any state law or county or municipal ordinance regulating the operation of motor vehicles in this or any other state, other than parking violations, shall notify his or her employer in writing of the conviction within thirty days of the date of conviction.