Mo. Rev. Stat. § 577.300: Leaving a child unattended in a motor vehicle — first and second degree — penalties.

1. As used in this section, the following terms mean:

(1) "Collision" , the act of a motor vehicle coming into contact with an object or a person;

(2) "Injures" , to cause physical harm to the body of a person;

(3) "Motor vehicle" , any automobile, truck, truck-tractor, or any motor bus or motor-propelled vehicle not exclusively operated or driven on fixed rails or tracks;

(4) "Unattended" , not accompanied by an individual fourteen years of age or older.

2. A person commits the offense of leaving a child unattended in a motor vehicle in the first degree if such person knowingly leaves a child less than eleven years of age unattended in a motor vehicle and such child fatally injures another person by causing a motor vehicle collision or by causing the motor vehicle to fatally injure a pedestrian.

3. Leaving a child unattended in a motor vehicle in the first degree is a class C felony.

4. A person commits the offense of leaving a child unattended in a motor vehicle in the second degree if such person knowingly leaves a child less than eleven years of age unattended in a motor vehicle and such child injures another person by causing a motor vehicle collision or by causing the motor vehicle to injure a pedestrian.

5. The offense of leaving a child unattended in a motor vehicle in the second degree is a class A misdemeanor.