Justice committee  I would pick something like 50, because my opinion is that people are impaired at a concentration of 50 milligrams of alcohol in 100 millilitres of blood. Just for your example, you could have somebody who is not used to drinking who could be impaired below 50, and then you could have somebody who is used to drinking, who routinely consumes alcohol, and they might not demonstrate outward signs of intoxication from the alcohol consumption.

Justice committee  That's correct. I would still consider that person to be impaired by alcohol above a concentration of 50, but can you look at them and see that they're having difficulty with walking and talking? Potentially, no. However, if you put them in a car and a sudden event happens, that's when they require all their faculties to respond to it.

Justice committee  Perhaps I could explain our process going into this when we were discussing the numbers. As I said before, we did look at other countries. Predominantly this is about smoking because of how THC gets in so slowly with regard to edibles. What is important is recency of use. You could take a number like 100 nanograms per millilitre and say that it is very recent use.

Justice committee  No. With respect to alcohol, because that's really predominantly what I testify on, as I am the chair of the drugs and driving committee but most of our cases are alcohol, certainly, within the scientific literature, impairment has been demonstrated at as low as 15 milligrams of alcohol in 100 millilitres of blood.

Justice committee  Then the answer is yes. If you smoke, regardless of your concentration, it's ill-advised to drive a car. There is a window during which I would expect that drug to have an effect.

Justice committee  I would agree with that, yes.

Justice committee  Is this with regard to testifying in court?

Justice committee  With the new bill, some work will be taken away from us, in theory, with regard to calculations for blood alcohol. The simple BAC calculation, or BAC extrapolation, can be done by somebody within the court system, by a judge or whoever is tasked with doing it. That will be taken away.

Justice committee  Not enough.

Justice committee  Yes. It's about the number of people. From my personal perspective, it takes approximately three years to train somebody after they've been hired. You don't just start the job, hit the ground, and go to court. It takes time to train people in this specific field.

Justice committee  For smoking, that's correct.

Justice committee  I would agree with the point that a person can be impaired below a concentration of five nanograms per millilitre. They can be impaired at a concentration of one nanogram per millilitre. Directly correlating a concentration to impairment is very difficult. With respect to impairment and THC, there are a number of factors that toxicologists consider.

Justice committee  Okay, just to put this in context, you're citing the report we wrote, in which we tried our best to flush out all of the issues with respect to cannabis and driving, as well as the other drugs. I will say that cannabis is not a simple drug. There are a variety of considerations with respect to different types of users, different types of use, and effects in the body.

Justice committee  Yes, the same.

Justice committee  Good evening. I want to thank you for this opportunity to speak on behalf of the drugs and driving committee, or DDC, of the Canadian Society of Forensic Science. I will take the time I'm allotted to introduce myself, tell you about the DDC, explain our process and our role, and give some background information, and I hope to clarify any scientific questions regarding the proposed new provisions.