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Vancouver Personal Injury Lawyers Discuss Marijuana and Driving

Drunk driving is the cause of many motor vehicle accidents and fatalities each year. Criminal consequences for drunk driving are well established, and personal injury law (Vancouver and Canada-wide) in relation to law suits for injuries caused by drunk drivers is well developed.

Marijuana-impaired driving is a comparatively less developed area of criminal and personal injury law, even though marijuana (also known as cannabis) is one of the most commonly used drugs in Canada. In fact, after alcohol, marijuana is the second most widely used impairing drug in the world. Marijuana Use by Drivers in British Columbia Many Canadians drive after using marijuana. British Columbians are no exception: as part of an evaluation of the impact of the Immediate Roadside Prohibition (IRP) legislation, a survey of drivers was conducted in five communities in British Columbia in June 2010 and again in June 2012. The study found more than 7% of British Columbia drivers tested positive for drugs. Cannabis was the most commonly detected substance. In a recent survey done (late 2017) with marijuana users, 39% admitted to driving after using marijuana. “Drugged Driving” The term “drugged driving” refers to operating a motor vehicle while impaired by any type of drug or medication, or a combination of drugs, medication, and alcohol. The active chemical ingredient in marijuana, tetrahydrocannabinol (THC), has the potential to significantly impair driving performance. Marijuana can decrease reaction times, distort time and distance estimations, cause sleepiness, and decrease concentration, all of which can impair one’s ability to properly control a motor vehicle. Even more severe impairment results when marijuana is combined with alcohol. Because marijuana impairs the skills required for safe driving, drugged driving has the same legal consequences as drunk driving. Difficulty Detecting Marijuana Impairment It is not easy to determine whether a driver is impaired by marijuana. The risk of drugged driving and how the risk varies with the amount of cannabis consumed is not well quantified. This uncertainty makes it difficult to develop effective road safety laws targeting drugged driving. Another major difficulty is detection of marijuana impairment. Unlike the breathalyser for alcohol testing, there is no widely accepted roadside test for marijuana impairment. THC cannot yet be measured with a cheap and reliable breath test. The presence of THC in the body can be measured by blood and urine tests, but if Canada is to limit THC content like it limits blood-alcohol content, or allow police to do roadside tests for it, it will need to make changes to the Criminal Code. The case of accused drugged-driver named Carson Bingley illustrates the difficulties with respect to detection of drugged driving. In 2009, Mr. Bingley drove the wrong way up an Ottawa street and hit another car in a parking lot. Police were called to the scene of the accident and noted signs of impairment, but the roadside test revealed a blood alcohol concentration well below the legal limit. The police had a “Drug Recognition Expert” administer sobriety tests at the scene. Mr. Bingley failed the sobriety tests and was charged with driving while drug impaired. Mr. Bingley admitted that he had smoked marijuana, and a subsequent urine test was positive for cannabis and other drugs. Despite that evidence, Mr. Bingley was tried but acquitted for the offence of driving while drug impaired. The police had a “Drug Recognition Expert” administer a 12 step drug recognition evaluation. Mr. Bingley admitted that he had smoked marijuana and the evaluation confirmed that. Mr. Bingley was charged with driving while drug impaired. The trial judge refused to admit the evidence of the DRE because the DRE was not an expert regarding the underlying science behind the evaluation. The appeal from that decision made its way up to the Supreme Court of Canada. The Supreme Court of Canada recently held that the DRE is an expert and his opinion regarding the evaluation is admissible, thus requiring another trial of Mr. Bingley at which the DRE’s expert evidence will be admitted. Proving the presence of cannabis in a driver is not the end of the matter, however. The Crown must also prove that there is sufficient active chemical from cannabis to induce impairment, at the time the accused was driving. The evidence required to prove this causation (ie that cannabis caused impairment) is a developing area of the law. Impact on Vancouver Personal Injury Law While fault in a criminal case is not determinative of fault in a civil lawsuit, the development of Canadian criminal law in relation to drugged driving will have an influence on personal injury law in Vancouver and across the country. As leaders in Vancouver personal injury law, we closely follow legal developments in relation to drugged driving and put them to use to help our clients succeed in civil lawsuits against drivers impaired by marijuana or other drugs.

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