{"id":107527,"date":"2026-02-06T16:13:29","date_gmt":"2026-02-06T21:13:29","guid":{"rendered":"https:\/\/brocku.ca\/brock-news\/?p=107527"},"modified":"2026-02-06T16:58:20","modified_gmt":"2026-02-06T21:58:20","slug":"nco-policy-brief-explores-impaired-driving-rates-following-cannabis-legalization","status":"publish","type":"post","link":"https:\/\/brocku.ca\/brock-news\/2026\/02\/nco-policy-brief-explores-impaired-driving-rates-following-cannabis-legalization\/","title":{"rendered":"NCO policy brief explores impaired driving rates following cannabis legalization"},"content":{"rendered":"

A newly released Niagara Community Observatory (NCO) policy brief says that while impaired driving rates rose after 2018, research is unclear regarding how much of that increase was due to the legalization of cannabis that year.<\/p>\n

The brief, \u201cChanges In Canada\u2019s Impaired Driving Rates Since 2018<\/a>,\u201d explores the impact of the legislative change on vehicular impairment.<\/p>\n

\u201cWas there any actual connection? What kind of evidence do we have?\u201d says its author, Brock University Associate Professor of Operations Research Michael Armstrong.<\/p>\n

To answer those and other questions, Armstrong surveyed research analyzing data from Statistics Canada, hospital emergency departments and police records.<\/p>\n

When looking at annual rates of impaired driving cases investigated by police between 2009 and 2023, he found that impaired driving rates rose overall.<\/p>\n

His analysis of reports showed a 31 per cent rise in the number of impaired driving cases overall between 2019 and 2023 in Canada compared to what was projected based on earlier trends. These increases were 26 per cent in Ontario and 22 per cent in Niagara.<\/p>\n

These reports included cases of impaired driving in four substance categories: alcohol, drugs, drugs-and-alcohol combined and unknown substances. Because the drug category does not identify the substance involved, Armstrong says it is difficult to gauge how often cannabis contributed to impaired driving in these cases.<\/p>\n

While the rates of alcohol-impaired and drug-impaired drivers caught by police both grew, the number of drivers impaired by alcohol increased four times as much as the number impaired by drugs.<\/p>\n

Armstrong attributes this overall increase in impaired driving mostly to the enforcement changes that happened at around the same time as cannabis was legalized in 2018.<\/p>\n

These measures include greater police powers to gather blood and breath samples from drivers, training for more officers to become drug recognition experts, increasing roadside checks and enabling police to suspend licences and impound cars instead of laying charges.<\/p>\n

Because of these measures, a greater number of people were caught driving while under the influence, he says.<\/p>\n

\u201cMy sense is that cannabis legalization did not lead to a huge jump in impaired driving,\u201d says Armstrong. \u201cIt undoubtedly accounted for some of the increase but was not a drastic one like some people had feared.\u201d<\/p>\n

The data contained within the NCO brief give a picture of impaired driving trends locally, provincially and nationally.<\/p>\n

These include that:<\/p>\n