Re: "Anyone can smell the problem: weed and driving" (Editorial, April 14)

You opined that "a staggering 50 per cent of the drivers" driving to and from cannabis stores "tested positive for recent cannabis use," and that "smoking weed and driving is also impaired driving."

Alas, the problem is not so simple. Drivers may test positive for cannabis metabolites in oral fluid for up to 72 hours after consumption, long after the effects have worn off, depending in part on how often the consumer partakes.

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