82 POLICE ASSOCIATION OF NOVA SCOTIA Rates of driving after cannabis use and related crash deaths and injuries may have increased in the last several years, as a result of rising usage rates of medical and recreational cannabis. The experience in Colorado and Washington, following the legalization of cannabis, also suggest an increased crash risk. • The percentage of cannabis-positive drivers in fatal crashes in Colorado, which had been decreasing, increased following legalization, and that increase was higher than in those states which had not legalized cannabis. (Source: S. Salomonsen-Sautel et al.,“Trends in fatal motor vehicle crashes before and after marijuana commercialization in Colorado” (2014) 140 Drug and Alcohol Dependence 137, at 140.The authors also reported that there were no significant changes in the percentage of alcohol-impaired drivers in fatal crashes in either Colorado or the Non-Medical Marijuana States.) • AWashington State study showed the percentage THC-positive drivers in fatal crashes approximately doubled in the year after recreational cannabis use was legalized. (Source: B.Tefft, L.Arnold & J. Grabowski,“Prevalence of Marijuana Involvement in Fatal Crashes:Washington”, 2010-2014 (Washington, DC:AAA Foundation for Traffic Safety, 2016), at 1.) Researchers note, and MADD Canada recognizes, that the simple presence of cannabis does not mean a driver is impaired. However, roadside surveys often find levels of cannabis high enough to impact driving ability. A 2010 British Columbia roadside screening study, for example, reported the majority of cannabis-positive drivers found had THC levels over 40ng/ml.The authors noted that the readings point to cannabis use just prior to or while driving, and they concluded that the vast majority of cannabis-positive drivers hadTHC levels that impaired their ability to drive safely. (Source: D. Beirness & E. Beasley,Alcohol and Drug Use Among Drivers: British Columbia Roadside Survey 2010 Ottawa: Canadian Centre on Substance Abuse, 2011), at 12 and 13) The Canadian Centre on Substance Use and Addiction estimates the annual cost related to cannabis-involved collisions in Canada to be $658 million. How common is cannabis use among drivers? MADD Canada’s statistical research has shown a growing incidence of driving after drug use.The number of fatalities involving drugs alone is double those involving alcohol alone. Cannabis, the most commonly-found drug, is present in almost half of the drug-positive fatal crashes. In 2014, road crashes claimed an estimated 2,297 lives. Based on testing of fatally-injured drivers, MADD Canada estimates 1,273 (55.4%) of these deaths resulted from crashes in which an individual was positive for alcohol and/or drugs: • 299 deaths, or 13%, occurred in crashes involving individuals who were positive for alcohol alone. • 618 deaths, or 26.9%, occurred in crashes involving individuals who were positive for drugs alone. • 356 deaths, or 15.5%, occurred in crashes involving individuals who were positive for both alcohol and drugs. It must be emphasized that the figures document the presence of alcohol and/or drugs and not whether the individual was legally impaired.While research indicates that most of the alcohol-positive individuals were likely impaired or very impaired, there is no comparable information on the drug-positive drivers. However, it should be noted that the drug tests are designed to detect the recent use of psychoactive drugs that adversely affect driving skills, rather than metabolites that merely indicate use of the drug sometime in the past. The prevalence of drug use among drivers is also reflected in recent studies and surveys. • Statistics Canada’s latest National Cannabis Survey (2nd quarter, 2018) indicated one in seven cannabis users (14%) reported driving at least once within two hours of using cannabis in the past three months, and one in 20 Canadians (5%) reported being a passenger in a vehicle driven by someone who had consumed cannabis in the previous two hours. • A roadside survey conducted by Manitoba Public Insurance found that 10% of drivers tested positive for some form of drug (more than half of those tested positive for cannabis).Alcohol, by comparison, was found in 2.4% of drivers. • A study of young people in British Columbia found that more than three-quarters of frequent users reported having been in a car or other vehicle when the driver (including themselves) had been using marijuana or other drugs. Does cannabis affect driving ability?(continued) (continued)