Missouri Revised Statutes Title XIX. Motor Vehicles, Watercraft and Aviation § 304.031. Traffic signal preemption system, use of, permitted when--violations, penalty

1. As used in this section, “Traffic Signal Preemption System (TSPS)” shall mean a traffic-control system designated for use by emergency vehicles, as defined in this section, to improve traffic movement by temporarily controlling signalized intersections.

2. The owner of a traffic control signal may authorize use of a TSPS by the following persons for the following purposes:

3. A TSPS used by an authorized person in an emergency vehicle or at a station where emergency vehicles are stationed shall preempt and override a device operated by any other person.

4. A traffic control signal operating device used as authorized under this section must operate in such a way that the device does not continue to control the signal once the vehicle containing the device has arrived at the intersection, regardless of whether the vehicle remains at the intersection. No motor vehicle driver shall be convicted of any traffic violation if there is evidence that TSPS has been used by a government official to improperly change the sequence of the traffic signals.

5. It shall be unlawful for any person not approved herein to use a TSPS to control traffic.

6. Violation of this section shall be deemed a class B misdemeanor.