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Cannabis effects compromise safe driving for over 5 hours


Although using cannabis is not a crime in British Columbia, driving after using it is a crime. It could have devastating consequences when cannabis-impaired drivers take to the roads. Tetrahydrocannabinol (THC), the active ingredient, affects drivers in different ways. It moves through the body and into the brain, affecting the parts of the brain vital for safe driving.  

The effects of different types of cannabis fluctuate from person to person. Regardless of a person’s composition and body size, dose, tolerance and other factors, cannabis and driving do not mix, and it is illegal to drive while impaired. According to a study funded by the CAA, THC could impair driving abilities for over five hours after inhaling cannabis. 

Compromised driving skills

Because THC in cannabis can compromise cognitive skills necessary for safe driving, cannabis doubles a driver’s risk of being involved in a collision. The following essential abilities are typically affected by cannabis: 

  • Attention 
  • Coordination 
  • Concentration  
  • Reaction time 
  • Distance-judging ability 
  • Capacity for making decisions 

Facts that cause concern

The following facts about cannabis are alarming: 

  • Cannabis can impair your ability to drive 5 hours after inhalation. 
  • In 8% of serious car accidents, drivers test positive for marijuana 
  • In Canada, 20% of millennials (18-34 years old) mistakenly think a person who is high can drive as well as or better than a sober person. 
  • Almost one in five British Columbia drivers have smoked cannabis and driven – or ridden in a car driven by a person who has recently done so. 

The injured passengers in cannabis-impaired drivers’ cars or occupants of other vehicles who suffered the consequences of the driver’s negligence may seek financial relief. They can file personal injury lawsuits in a British Columbia civil court to recover damages. Navigation of such claims could be more complicated if it involved cross-border personal injuries.