Impacts of Cannabis Legalization on Traffic Accident in Colorado, USA
kpt. Ing. Tomáš Kratina, National Drug Headquarters of the Criminal Police, and Investigation Service of the Czech Police, Czech Technical University in Prague, Faculty of Biomedical Engineering

Following a referendum Colorado, one of the US states, is one of the country that decided about legalization of cannabis for so-called ‘recreational use’ in 2014. Thanks to legalization, the proportion of negative impact of marijuana use increased in many human activities, including transport. Statistical data processed by the state authorities presenting annual results in their reports are on an increasing trend comprising not only negative phenomena associated with transport. The number of arrested persons who are under the influence of marijuana and killed persons in on increase.  There is a rise in concentration of delta-9-THC in the blood of arrested drivers and the number of hospitalized ones. Specialist publications summarize the way marijuana affects the driver’s ability to drive a motor vehicle in road traffic. In particular, there is a significant decrease in the perception and recognition of lights, errors in the oversight of traffic lights and traffic signs and insensitive control of the vehicle. There is also significantly reduced performance when critically tracking a given task, reducing the number of right decisions over time and extending response times, etc.

Key words: Cannabis Legalization, Traffic Accident, Driver Influence, Colorado, Marijuana.