How does cannabis affect driving ability?
Driving skills are affected in specific ways when a person has consumed a certain amount of pot. This impairment increases with the amount of THC (the compound that gives pot its high) a person has in his/her system. While drivers have been found to do certain things to adapt to their impairment, like slowing down, this attempt to compensate does not eliminate the risks of driving high. It has long been established that pot affects tracking ability, meaning that drivers who are under the influence of a certain dose of THC have been found to have a harder time following their lane. Pot reduces a driver’s ability to perceive changes in the relative speed of other vehicles and to adjust his/her own speed accordingly. Pot has been found to increase the reaction time needed to respond to an emergency decision-making task, such as adapting to changes in speed of the vehicle ahead or to the vehicle’s brake lights. A driver needs to notice something in order to respond to it and that has to do
