In 2024, GHSA and Responsibility.org provided a $28,750 grant to the Missouri State Highway Safety Office (SHSO) to strengthen enforcement capacity and address cannabis- and polysubstance-impaired driving.
In 2024, the Governors Highway Safety Association (GHSA) partnered with the Foundation for Advancing Alcohol Responsibility (Responsibility.org) to provide a $28,750 grant to the Missouri State Highway Safety Office (SHSO) to strengthen enforcement capacity and address cannabis-impaired and polysubstance driving.
Substance-impaired driving remains a significant threat in Missouri, contributing to 20 percent of all crash fatalities between 2019 and 2023. While alcohol continues to be the leading factor, there has been a steady rise in impairment involving prescription medications and illicit drugs. Cannabis is the most common drug detected in combination with alcohol and other impairing substances, raising new challenges for enforcement and prosecution.
To respond, the Missouri SHSO partnered with Extract-ED to deliver a series of Green Lab trainings designed to improve officer ability to detect cannabis impairment.
Three Green Labs were held during the grant cycle: October 2024 in Springfield, February 2025 in Kansas City and April 2025 in St. Louis. More than 60 officers participated, observing cannabis impairment in a controlled environment. Under instructor guidance, officers practiced administering Field Sobriety Tests while medical staff ensured participant safety.
Each Green Lab engaged a broader network of stakeholders, including prosecutors, judges, safety officials and law enforcement representatives from Missouri and neighboring states. Cannabis industry liaisons contributed to the sessions and in two of the labs, a driving simulator was used to demonstrate the real-world effects of impairment on driving performance.
The Green Labs enhanced officer knowledge of cannabis impairment, strengthened collaboration among law enforcement and safety partners and elevated Extract-ED’s role as a resource in impaired driving training. Officers noted that cannabis impairment often presents differently from alcohol impairment and can diverge from Drug Recognition Expert (DRE) training, highlighting the value of specialized instruction for polysubstance cases.
Consumer participation also exposed a critical public perception gap. While most individuals acknowledged the dangers of alcohol-impaired driving, many did not view cannabis use as equally impairing. Some participants admitted they should not drive after using cannabis while others believed they could do so safely. This finding emphasized the need for ongoing public education and awareness campaigns to address misconceptions about cannabis impairment.
