Cannabis legalization and driving go hand in hand in Canada

The legalization of cannabis in Canada has shown »no statistically significant change in the average cost per claim and the frequency of claims« , according to a new report of the Canadian Institute of Actuaries (CIA) and the Casualty Actuarial Society (CAS). In other words, the legalization of cannabis has not increased the number of road accidents in Canada.

«The literature review shows that if cannabis impairment affects driving behavior, this behavior is not always riskier ; For example, slower speeds and longer following distances have been reported by drivers under the influence of cannabinoids,» says the study entitled Assessing the Impact of Marijuana Decriminalization on Vehicle Accident Experience.

«Observational studies of road accidents report mixed results, most often failing to detect significant effects, particularly over the long term.»

The cannabis legalized in Canada October 17, 2018. In the months and years since legalization, industry players have reported little or no effect on auto claims.

For the CIA/CAS study published on December 7, Canadian and US data from 2016 to 2019 were used, including official reports on private vehicle collisions and casualties in Canada, and fatal accidents and weather factors in the US. To isolate and therefore rule out’impact of the COVID-19 pandemic, Data from 2020 or later are not used. For each data source, statistical and machine learning models have been chosen to take account of the different sources of variability.

The analysis of the 10 Canadian regions took into account regional differences and modeled a basic linear trend that was also observed in the pre-legalization data alone.

«The analysis showed no statistically significant change in average cost per claim and claim frequency after the legalization of cannabis in Canada,« the report states. «Quarterly data available for Quebec led to similar conclusions..... The study did not detect any statistically significant persistent impacts of decriminalization.»

Canadian data came from private vehicle collisions by accident year» in the annual reports of the General Insurance Statistical Agency (which includes insurance information from most Canadian regions, with the exception of public automobile plans) and the Groupement des assureurs automobiles in Quebec.

«The methods used in this research include improved statistical models, machine learning and other data science techniques. The models used high-resolution weather data to account for the effects of meteorological factors,» noted the report's authors.

«The results relating to claims frequency per 100 vehicles lead to the same conclusions as the results relating to average cost per claim», which implies the absence of significant effects», says the report.

The debate on THC levels admissible while driving and ways of measuring impairment rather than a strict rate.