What About Zero Drugs?

One of the conditions attached to the driver's license of any new driver in British Columbia's Graduated Licensing Program (GLP) is that the driver must have zero blood alcohol when they are operating a motor vehicle. Of course, the idea behind this is that the driver has enough to worry about while driving the vehicle without adding alcohol to the mix. So, what about drug use?
This question came to my mind one afternoon while I was observing a lineup of vehicles stopped for the flag person at a construction zone. I found a lone male GLP "N" driver who wasn't wearing his seatbelt and pulled him out of the line when it moved on. As soon as I walked up to the driver's door I could smell the marihuana smoke inside, and since the windows were down and he was alone, I knew who had been smoking.
His green bordered license with the zero alcohol condition printed on the back had me thinking about other reality changing drugs. Shouldn't a new driver have a zero tolerance condition for those as well? He spoke to me candidly about smoking a joint while waiting for the construction and I made careful notes and a no charge drug seizure.
Before the end of my shift I contacted the Superintendent of Motor Vehicles. No, we're not interested was the response. The Superintendent would only take action if the driver was issued a 24 hour suspension or was charged criminally for impaired driving by a drug other than alcohol.
The situation is the same today. A new driver cannot drink and drive, but it's OK to toke up and drive as long as you don't do enough to be suspended or charged. I repeat, what about zero drugs?
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