Madam Speaker, I am happy to speak to Bill C-46 today, a bill that would change the Criminal Code in relation to offences related to driving under the influence of alcohol, marijuana, and other drugs. The bill is essentially paired with Bill C-45, a bill that would legalize marijuana, so it is safe to say that it is meant to provide some comfort to Canadians concerned about the dangers of driving under the influence of marijuana or THC as much as it is about alcohol impairment.
The NDP clearly stands for deterrence to driving while impaired. Canada has a terrible record of deaths and injuries related to impaired driving. About 1,000 Canadians are killed each year in traffic accidents involving impaired driving.
Others have spoken eloquently on that aspect of the bill, but what I want to spend most of my time here today talking about are the concerns about the difficulty of testing, in any meaningful way, for impairment by marijuana.
I sat on the justice committee for one of the meetings set aside to consider Bill C-46, and we heard very interesting and compelling testimony about roadside testing for marijuana. We are all used to the concept of testing for alcohol levels through roadside breath tests. These tests produce results that accurately measure blood alcohol levels. Blood alcohol levels rise and fall in a predictable manner that relates closely to impairment. We can therefore deduce impairment from alcohol blood levels, and we do that in roadside tests every day across the country. We have per se limits for alcohol impairment, usually .08% or .05% blood alcohol.
The psychoactive ingredient in marijuana is THC, and it acts in a very different physiological way than does alcohol. Unlike what happens when drinking alcohol, THC levels rise very quickly in the blood when marijuana is smoked, and while those initial levels are high, the person may not be significantly impaired, because the effects of THC occur when the THC leaves the blood and binds to fatty tissues in the brain. THC binds to fatty tissues so strongly that blood levels generally drop very rapidly. When impairment levels are high, THC levels in the blood are usually very low, so THC levels in the blood do not necessarily relate at all to the level of impairment.
Impairment also differs significantly between alcohol and THC. Alcohol impairment involves a loss of motor control, hence the famous tests such as walking a straight line or standing on one leg. THC impairment affects faculties such as reaction time rather than motor control. People impaired by THC will often report that they know they are impaired, so some are more likely to decide not to drive, or they will drive more slowly. Alcohol impairment has essentially the opposite effect, so drunks drive more recklessly. I do not want to suggest that people under the influence of marijuana are safe drivers, just that we have to test for impairment in a very different way.
At committee we also heard from a toxicology expert that we can back extrapolate from a blood alcohol level measured at some time after an incident to assess the level that would have existed at the time of that incident. We cannot do that for THC. If a driver involved in an accident was found to have some level of THC some hours after the fact, we could not, with any scientific certainty at all, know what the THC level was at the time of the accident. Even if the level was tested at the time of the accident, we would have no way of relating the THC level with impairment.
Dr. Thomas Marcotte, an expert in testing for THC and impairment, from the University of California, San Diego, gave extensive testimony on these difficulties. He and his colleagues have found no way to usefully match THC levels with impairment. He and others have found that it is not only difficult to relate THC blood levels to impairment but that regular users of marijuana will have chronic low levels of THC in their blood, with no impairment at all. This is extremely problematic for the task of finding a meaningful way to test for THC impairment on the roadside.
We are making it legal for Canadians to use marijuana. Indeed, it is already legal for users of medical cannabis. If some of these law-abiding Canadians have chronic low levels of THC in their blood, and we use some per se limit of THC as a surrogate for impairment, then we are essentially saying that yes, people can legally use marijuana or medical cannabis, but they can never drive again or they could be charged with impaired driving, despite not being impaired.
Also at committee we heard from two witnesses from Australian police forces. Australia has used extensive roadside testing for alcohol and drugs, which others have mentioned in this debate. Much of this testing is through what they call “booze buses”, which process hundreds of thousands of Australians annually. They literally close off highways and test everyone for alcohol levels, while a smaller sample are screened for drugs.
Australian police also carry out so-called random testing at their own discretion, usually in neighbourhoods they feel need scrutiny. It is this type of testing the NDP has great concerns about, as it is clearly open to racial profiling. My colleague for Victoria on Friday covered some of these concerns very well in his speech, so I will leave this point, but I am sure members will hear more about it from my colleagues later today. However, one of the serious issues with Bill C-46 is that it undermines the present system of testing only after reasonable suspicion of impairment.
The Australian police also testified about the test they use for THC. These tests are expensive: about $30 for the preliminary test and ten times more for a secondary test given to those who score positive. Anyone found with any level of THC is charged with impaired driving and has a licence suspension. Now, this works in a jurisdiction such as Australia, where marijuana is illegal. However, as we have heard from experts at committee, people who use marijuana regularly, and there are many across Canada, including thousands who use cannabis for medical reasons, will have chronic levels of THC in their blood. If they lived in Australia, they would not be able to drive at all for fear of being charged for impaired driving, even when they were not impaired, and even if they had not used marijuana for many hours or even days.
How do we test for marijuana impairment? As I mentioned before, THC impairment presents as a slowing of reaction time and other similar faculties, but not a loss of motor control. Dr. Marcotte testified that he and others were working on developing iPad-based tests that would test for these abilities. However, we hear from the government side in this debate that its members are confident that meaningful roadside mouth-swab tests will somehow be developed in the next few months, despite expert testimony that any test measuring THC will be meaningless as a measure of impairment. If we use the Australian model, we will be criminalizing marijuana users who have chronic levels of THC in their blood, even though they have not used marijuana that day and are in no way impaired. We need a better solution to this problem.
On July 1 next year, Canadians will be able to use marijuana legally, and many will be using and driving. We need a system that tests for impairment from marijuana, not for meaningless THC levels.