Evidence of meeting #65 for Justice and Human Rights in the 42nd Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was impaired.
A recording is available from Parliament.
Chair, Drugs and Driving Committee, Canadian Society of Forensic Science
I would agree with that, yes.
Liberal
Ron McKinnon Liberal Coquitlam—Port Coquitlam, BC
Okay.
Dr. Watson, I'll transfer my attention to you. Welcome and good morning. I know it's very early there.
You mentioned a number of activities, a number of efforts, over the years, around deterrence. Would you care to comment on the relative efficacy of mandatory minimums versus, say, random breath testing? Which is more effective, or is one more than the other?
Adjunct Professor, Faculty of Health, Queensland University of Technology, As an Individual
Unfortunately, it's difficult to disentangle the Australian experience, really, to answer your question, because one of the key things is that although when random breath testing was introduced across the states it was the initiative that caught a lot of public attention and really, I think, the driving force behind the general deterrent effect, at the same time, we enhanced our penalties. It was very much the case that mandatory loss of licence, licence disqualification, was introduced for drunk drivers.
Now effectively, in all the states, with a few anomalies, if you get caught for drink driving in Australia, you will lose your licence. We have a graduated set of penalties, so the higher your blood alcohol concentration, the higher the penalty will be. That includes the fine and also the period of disqualification. There's no doubt that the threat of losing your licence, that general deterrent threat, has had a big part in our success in terms of reducing drink driving. At a public level, that has largely been through the highly visible random breath testing, but that threat had teeth to it, had meaning, because drivers were concerned about losing their licences. I think the two go together, and I would certainly be encouraging that.
As a psychologist, I would argue that you want to ensure that there is a higher degree of unpredictability in the activity but a high degree of certainty that if you are detected you will be punished, and that punishment will be reasonably severe. In fact, the literature suggests that it's the certainty of the punishment and not necessarily the severity that's most important.
I would certainly be encouraging you to think about them as a package of initiatives in which you have the random breath testing to increase that general deterrent effect, and some form of mandatory penalty, which means that the likelihood that drivers will lose their licences if it is detected is very high and in fact there's a very high certainty of some form of penalty.
Liberal
Ron McKinnon Liberal Coquitlam—Port Coquitlam, BC
The random testing goes to the certainty of detection, which ties to the certainty of a penalty. Is that correct?
Adjunct Professor, Faculty of Health, Queensland University of Technology, As an Individual
That's right.
From a criminological perspective, you're wanting to optimize that general deterrent that relates to the likelihood of detection, and then if you are detected, the punishment you will receive will be certain, reasonably severe, and also swift.
Liberal
The Chair Liberal Anthony Housefather
Thank you very much, Mr. McKinnon. That's it for your questions.
Mr. Liepert.
Conservative
Ron Liepert Conservative Calgary Signal Hill, AB
Thank you, Chair.
I have one quick question. I don't know about you, but I'm getting to the point where I could really use a drink. I'm walking back to my apartment, not driving.
Professor Watson, your presentation was around mandatory breath testing as applied to alcohol. Our government here is proposing to legalize marijuana. We probably wouldn't have this particular piece of legislation before us if we weren't going down that path.
Do you have any advice around the legalization of marijuana, some suggestions on how we may ensure that smoking and driving isn't a problem? I'd like to see if you have any thoughts around that.
Adjunct Professor, Faculty of Health, Queensland University of Technology, As an Individual
At the moment in Australia, there's no push to legalize marijuana. There is beginning to be a push for it to be used for medical purposes. In that respect, the Australian situation is quite different. Indeed, as you may be aware, as early as 2003, the Australian states started introducing random roadside drug testing. We have it for three specified drugs: cannabis, methamphetamine, and MDMA—ecstasy. I know one of my Australian colleagues will be telling you more about that later.
A point I'd like to make about that is that I think there was strong support for that at the time in the community. It was not necessarily controversial partly because at the time the legalization of marijuana wasn't something being considered. The Australian experience is that there's growing concern about the use of cannabis and its effect on driving. That's what underpinned the introduction of random roadside drug testing.
A point, though, that I would like to make is that, as we introduced random roadside drug testing, that meant that police resources were being used for that purpose as well as for testing for alcohol. I think sometimes there's been a tendency to think that we can take resources from drink driving enforcement, in other words from random breath testing, and devote them to random roadside drug testing.
Whilst I am not at all expressing a concern about random drug testing per se, the point I want to make is that, if you go down the track of some form of increased drug testing, it's important that you don't sacrifice breath testing for alcohol as a result of that.
If I look at the literature, from what I've seen, the highest crash risk is still being shown for the use of alcohol. Whilst there's also an increased crash risk for drugs, when it's most pronounced is when it's being used in conjunction with alcohol. From a road safety point of view, I'd be arguing that a very high priority is increasing the amount of breath testing in order to reduce alcohol-related crashes. If you go down the track of introducing some form of drug testing, that shouldn't in any way detract or cause some compromise of the amount of breath testing that is performed.
The Australian experience is that, if you can achieve high levels of random breath testing, it produces results in terms of reducing alcohol-related fatalities.
Liberal
The Chair Liberal Anthony Housefather
Thank you very much, Dr. Watson.
Mr. Cooper, you can ask a short question, then so can Mr. Cannings and Mr. Fraser.
Conservative
Michael Cooper Conservative St. Albert—Edmonton, AB
Thank you, Chair.
I'll just to follow up with Ms. Wallage.
Maybe it would be helpful if you could explain to me what the connection is between impairment and THC levels. I look at some of the studies, and some of the evidence said that if you have five nanograms or more, you may not be impaired, and if you're under two nanograms, you may be impaired.
What is the connection? It seems to me that THC tells us that someone has used marijuana, but on the question of impairment, what is it telling us when someone has five nanograms versus one nanogram?
Chair, Drugs and Driving Committee, Canadian Society of Forensic Science
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. Basically, the person is smoking and somebody is taking a blood sample at the same time. Toxicologists could get behind that. It would be recent use. But this is not reality for how it looks on the road, so we are trying to incorporate studies that looked at concentrations that could potentially be associated with recent use, as well as incorporating that no back calculation can be done, and that it takes time to get a blood sample.
On that note, with regard to the legislation, a blood sample has to be taken within two hours of the offence or else there is nothing to catch that result afterwards. If a blood sample is taken two and a half hours later, there's nothing in this bill that can happen, because there is no back calculation.
Five was the number that was decided upon because in general the literature pointed towards occasional users, among them five would mean recent administration for smoking. This comes with a caveat that it does not include those chronic users who have residual levels in their bloodstream for extended periods of time. As well, there aren't a lot of studies on the increase of potency that's available now.
That was our idea behind coming up with these numbers. One nanogram meant recent administration, as far as we can say that. I mean, there will always be exceptions to the rule. All those other factors were built in. Two was suggested just because there are people who can certainly be impaired below a concentration such as five, and the THC drops so rapidly that you could be at two even though there was recent administration.
NDP
Richard Cannings NDP South Okanagan—West Kootenay, BC
Dr. Watson, I have some quick questions about the roadside drug testing you mentioned for Australia.
How is that structured? How random is that? In terms of the amount of time and the resources it takes, how long does it take per individual tested compared with, say, the booze buses?
Adjunct Professor, Faculty of Health, Queensland University of Technology, As an Individual
The random roadside drug testing does take a considerably longer time than the random breath testing. In the case of random breath testing, drivers are really only detained for 30 seconds to a minute, let's say.
In the case of the roadside drug testing, there's an initial saliva test done. I believe that takes about five to 10 minutes. If that's positive, the drivers are then taken to a bus, where they are given a second oral test, which takes about another 15 minutes. The overall process for testing is a longer process.
In addition, the random roadside drug testing is quite a lot more expensive than random breath testing. For example, in the case of breath testing, once you've invested in the preliminary breath-test kit, the ongoing costs are really just the cost of the tube into which the driver blows. In the case of the random roadside drug testing, the saliva tests are more expensive. I believe they're in the order of $30 each. I'd suggest that you ask that question of my colleague from Victoria, who I believe will be talking to you.
The upshot of this is that in Australia nowhere near the number of drug tests are performed at the roadside as compared to breath tests. As a result, there does tend to be more targeting of that activity. It tends to be focused more towards recreational users, and also towards truck drivers, and that is because of their use of methamphetamines for staying awake whilst driving. In other words, the drug testing tends to occur more at particular times, and particularly late at night, in areas where recreational drug users or truck drivers might be.
The overall upshot of this is that in terms of the very strong boots-and-all effect that was obtained for breath testing in Australia, it's been difficult to achieve that for the drug testing. From a resourcing point of view, the police have needed to allocate additional resources to cover the higher costs of the saliva drug tests. This really requires a specific allocation of budgets to the police for them to be able to do additional drug testing, in order to maintain the breath testing at the current levels.
Liberal
The Chair Liberal Anthony Housefather
Thank you very much.
Before we wrap up, I just want to follow up on Mr. Cooper's question to Ms. Wallage.
Ms. Wallage, you made it clear that there's not necessarily a direct correlation between five milligrams of THC in the blood and impairment. As we know, the law basically has different categories of offences. One is driving while impaired under alcohol or drugs. Another is exceeding a per se limit. Would you agree with me that it would be the same in the case of alcohol? You could have somebody below .08 who is very impaired because they're not used to drinking alcohol, and you could theoretically have somebody over .08 who was not showing signs of impairment. Wouldn't it essentially be the same?
Chair, Drugs and Driving Committee, Canadian Society of Forensic Science
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. They may be able to get from point A to point B without too much difficulty. If they are challenged on the roadside, meaning if there is a sudden or unexpected task, that's when impairment becomes an issue.
The same goes for THC, in that if you are a chronic user, you do develop some tolerance to the drug. That doesn't mean the drug is having no effect on you, but it does mean that you would have to increase your dose to achieve a similar effect to what you are looking for, so there can be people who are impaired at quite a bit lower level than others.
Liberal
The Chair Liberal Anthony Housefather
There could be people who are over that, but you would consider them impaired even if they were showing fewer visible signs of impairment than somebody else was, the same as you would for somebody over 50 for alcohol based on the level that you propose to use.
Chair, Drugs and Driving Committee, Canadian Society of Forensic Science
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.
Liberal
The Chair Liberal Anthony Housefather
Thank you.
I want to thank this witness panel. You have provided a lot of very useful information.
I especially want to thank you, Dr. Watson, for testifying from so far away so early in the morning.
I'd like to thank everyone. We're going to take a short recess till the next panel comes up, and I'd like to ask the members of our fourth panel to please come up.
Liberal
The Chair Liberal Anthony Housefather
We are now ready to move forward with our fourth panel of the day.
It is a great pleasure for me to welcome Mr. Thomas Marcotte, who is from the department of psychiatry at the University of California. He is representing the Center for Medicinal Cannabis Research. Welcome, Dr. Marcotte. It's a pleasure to have you.
From Australia, the Victoria Police, we have Doug Fryer, who is the assistant commissioner of road policing command. Thank you so much, Mr. Fryer, for joining us. It's very much appreciated.
We're going to start with the testimony of Mr. Marcotte.
Mr. Marcotte, the floor is yours.
Dr. Thomas Marcotte Assistant Professor, Department of Psychiatry, University of California, Co-Director, Center for Medicinal Cannabis Research
Thank you.
Good evening. I appreciate the opportunity to share some information as you consider Bill C-46, an act to amend the Criminal Code.
I'm Tom Marcotte. I'm a professor of psychiatry at the University of California San Diego, and co-director of the University of California Center for Medicinal Cannabis Research. I'm an investigator on two current studies examining the impact of cannabis on driving.
Today I'd like to provide some background on the challenges in determining whether an individual's driving has been impaired by cannabis.
In controlled simulator and on-road studies, it's been well established that acute cannabis intoxication results in slowed reaction times, including delays in braking, reduced ability to maintain one's lane position—in other words, swerving—and reducibilities relating to the judgment of speed and distances. The effects of cannabis are amplified by alcohol, although it's not resolved as to whether this is an additive effect or synergistic, in which the two combined are worse than simply adding the effects together. Also, in contrast to alcohol, cannabis users are more likely to judge themselves to be impaired and to adjust behaviour, by driving more cautiously, as one example. However, of course, this is not universal.
Findings from the real world have been mixed. Some studies have found a twofold increase in crash risk when THC is present, while other studies have found no increased risk once adjusting for factors that often travel with cannabis use and risky driving, such as younger age and being male.
Here's one example of the difficulty in interpreting crash results from the states that have legalized cannabis.
In Colorado, it was widely publicized that there was a dramatic 50% increase in the number of fatalities in which marijuana was present following legalization. However, as seen in this next graph, there was only a marginal increase in the total number of crashes in that same period. This mirrored recent data demonstrating that, at a national level, there was also an increase in fatal crashes.
What is clear is that at this same time, the State of Colorado increased the amount of screening they were doing to detect THC. Therefore, it is unclear whether the increased prevalence of fatalities with THC present represents a situation in which increased cannabis use might have led to more fatalities, or whether it is primarily a case that authorities are more frequently looking for the presence of cannabis and finding it.
On the other hand, a recent report has indicated that there has been an increase in insurance collision claims in states where recreational cannabis has been legalized compared with other states. These are the much more common non-fatal crashes. When examining claim rates in Colorado, Washington, and Oregon, the authors found a 3% increase in claims relative to states that did not legalize use, with there being some variability between the states.
What might be some of the reasons that we see significant effects during controlled studies but a more modest effect in the real world? There are a number of possibilities, but to name just a few, in part, epidemiologic findings are based upon imperfect data. For example, the fatality reporting system in the United States often has incomplete reporting, and there's typically a significant delay between the time of a crash and the collection of blood. In addition, THC can be detectable in the blood long after the impairing effects have resolved. Thus, the impact of acute intoxication may not be readily apparent in these analyses, since the THC-positive group includes a much larger number of individuals who might have smoked much earlier and were not impaired at the time that the blood was collected.
On the other side, it is also possible that in some of our studies, while we're able to detect acute effects of cannabis on tasks such as swerving, they may not be of significant magnitude to dramatically affect real-world driving. As an example, in a study of low-dose THC for the treatment of spasticity in multiple sclerosis, we found a significant effect on driving two to three hours after dosing. However, the magnitude of that effect was not dissimilar to what other studies have found for individuals in the initial phases of starting antidepressants, or the residual morning-after effects of taking a sleeping medication the night before.
Drug recognition evaluations are the current gold standard for establishing substance-impaired driving. We're currently in the midst of a large study, funded by the State of California, to better characterize the impact of cannabis on driving, and to investigate whether there are additional effective approaches to identifying those individuals who are or are not impaired due to cannabis.
As part of this study we're working with DRE instructors to explore the validity of select components of the DRE evaluation, as well as assaying for the presence of THC, its metabolites, and other cannabinoids to determine whether they might provide reliable information regarding the time since the participant smoked or, ideally, relating to driving impairment.
Another unique aspect of this study is that we are utilizing novel iPad-based assessments to see if such tests might serve as a useful adjunct to the DRE evaluation. Unlike alcohol, where impairment readily presents itself physiologically, such as staggering and difficulty walking, cannabis effects are primarily cognitive and a current DRE evaluation includes only modest assessments of these abilities.
Particularly relevant to Bill C-46, studies to date raise concerns regarding the validity of using THC levels in blood to identify cannabis-impaired drivers. For example, a study by the American Automobile Association examined 602 cases in which DREs have identified drivers as being impaired, with THC being the only substance identified in the blood.
In this graph, the level of THC runs across the x or the horizontal axis and a per cent of drivers with that THC level is represented on the y or the vertical axis. As you can see in these impaired drivers, there was a wide range of THC levels. The median value or number where half the drivers were above and half the drivers were below was around five, indicating that 50% of these impaired drivers had values below the five nanograms per millilitre cut point at the time the blood was drawn. Thus, drivers can be impaired, yet have THC blood levels below a cut point that some governments have chosen as being indicative of driving under the influence.
Conversely, the table on the left shows that individuals who are likely unimpaired can also have detectable THC levels in their blood, even days after smoking. In this case, participants stayed in a hospital for 30 days so they could be monitored for any cannabis use. They then smoked cannabis and blood was subsequently drawn each day. As you can see in this table, some individuals were registering values of two nanograms per millilitre of THC, even though it had been up to a week since they smoked.
Why is it that we can have individuals with low levels of THC who are impaired, as well as individuals with low levels who are not impaired? The graph on the right is from Dr. Marilyn Huestis, a researcher in cannabis pharmacodynamics. Across the bottom we see THC levels and on the side we see, in essence, how high the person is feeling. This figure shows time in a counter-clockwise fashion, so as you see 1.8 minutes is the first and second is 4.5 minutes and so forth. After smoking, THC levels rise very rapidly so they reach a peak in about 10 minutes. At the same time the person is increasingly feeling high, so you see going to the right it's increasing, but it's also going up, so they're feeling higher. At this point, however, THC levels begin dropping to the point where about an hour after smoking they're now down to fairly low levels as you move across to the left in this graph.
The person, though, is still feeling high during this time. A few hours after smoking the highness starts diminishing, so it starts dropping down the vertical, but THC levels are not changing dramatically during this period. As you can see, it's between zero and 10. This tells us that someone can be high with elevated THC levels, someone can be high with modest levels, someone can be high with low levels, and someone can also have low levels and not be high. To further complicate this, Dr. Huestis has demonstrated that these patterns vary, depending upon whether one is a frequent or infrequent smoker.
At least for screening, oral fluid instruments hold some promise, they're easy to administer, relatively non-invasive, and may help identify individuals who recently used cannabis. This approach, however, is also not without complications. This graph shows results from a study of oral fluid THC levels in individuals who smoked a 6.8% THC cigarette. More studies are needed and ours is assessing the issue, but in general it's believed that the most significant impairing effects happen within the first few hours of smoking and then dissipate over the following few hours.
As you can see here in this graph, however, at least in this one study, a proportion of individuals were at or above a five micrograms per litre cut point in oral fluid eight to 10 hours after smoking.
I mentioned earlier that we have a study going on. If the group is interested, during the discussion I'd be happy to provide more details, but for this purpose I'll skip it and just end with a few concluding points.
Per se laws can be very effective, but this is particularly true when there is a robust relationship between fluid levels and actual driving impairment, as there is with alcohol. As can be seen in some of the data presented earlier, I don't think this is yet the case for cannabis. I'm also aware from attending many meetings that prosecutors remain concerned that a cut point designating impairment may lead the public to assume that a driver below that cut point is not impaired or is less impaired. As seen in the DRE data I presented earlier, low levels do not necessarily mean low impairment.
Some individuals have also expressed concern that the DRE evaluations may not be adequately sensitive to the effects of cannabis and that one should use fluid levels to identify impairment. I would argue that it is very important to continue to use behaviour as a key indicator of driving-related impairment given the uncertainty in interpreting fluid levels.
Last, I encourage you to support additional research into identifying new methods that might help law enforcement identify both those who are impaired and those who are not impaired due to cannabis. This includes biological, psychophysical, and behavioural approaches.
As you know, the complexities associated with detecting cannabis-related driving impairment also have increased our awareness regarding the continuing problem of impairment due to prescription medications. Perhaps new approaches to detecting impaired driving would end up being applicable to these drug classes as well.
Thank you, and I'm happy to take any questions.
Liberal
The Chair Liberal Anthony Housefather
Thank you very much, Dr. Marcotte.
We're going to turn it over to Mr. Fryer for his presentation.
Welcome to our committee.
Assistant Commissioner Doug Fryer Assistant Commissioner, Road Policing Command, Victoria Police
Thank you, and thank you for the opportunity to address the standing committee, and hello from way down at the bottom of Australia.
My name is Doug Fryer. I'm the assistant commissioner of road policing in my state. Just to paint the landscape, Victoria has a population of six million, and we have a driving population of four and a half million people who either ride or drive. My role as the head of practice for road policing is to guard the state around all activities of law enforcement. Our police force is quite large. We have about 19,000 police for our state, and my command of just road policing is about 1,100 highway patrol professionals.
Relevant to your standing committee, I suppose you have activity around both drink and drug driving. To lay the landscape, Victoria, Australia, was the first in the world to bring in randomized drink driving testing in 1976. In 1976 we had about 950 people die on our roads. The population was then three million. Close to 450 of those who died had in excess of .05 in their system for alcohol, and that is our legal limit right across Australia. In contrast 40 years on, last year we had 291 die on our roads, and we had 26 people who had in excess of .05.
In 2007 again Victoria was leading the world in studying randomized drug testing. Unlike, I believe, both the United States and Canada, we practise a general deterrence model in both drink and drug driving. We aim every year to test 4.5 million people for alcohol on the side of the road. We do very general deterrence. We block roads and put everyone through drink driving testing, but our drug testing regime, again, is leading our nation with 100,000 randomized drug tests of drivers or riders every year.
What concerns us, whilst I mentioned that 26 people died in excess of .05 last year, was that we had 57 who died with illicit drugs in their system, and there were a further seven who had both drugs and alcohol.
Relevant to your committee in relation to cannabis, last year we tested 100,000 people. We used a roadside saliva test 100,000 times. That's the style. It takes just a swipe of the tongue, and within six minutes we get a result. Of the 100,000 tests we did, we had 9,200 then move to the evidentiary test, so 9,200 people out of 100,000 tested positive for illicit drugs at a strike rate of one in 11, which really concerns us.
The idea of a general deterrence model with the preliminary oral fluid test is not around impairment. If we see drivers we believe to be impaired by either drugs or alcohol, my members are supposed to do what you would call a roadside sobriety test, and if they fail the sobriety test, we then take blood from them. The method we used for the 100,000 tests is around general deterrence, and it's off the back of our learnings from our drink driving general deterrence.
Of the 9,200 that were positive last year, about 73% were with methamphetamine, and the rest were with cannabis. We have zero tolerance. I know there was discussion around the five-nanogram level. Our threshold is that if we can detect it—and this has been tried and tested in our courts since 2007—then there is impairment. As Dr. Marcotte advised, the level of impairment we see for any detectable level is equivalent to that of about .1 for alcohol and doubles the chance of having a crash. For me, it's about separating the behaviours of using any type of illicit drug and driving. It's not the moral debate of whether they should use it or not. It's around separating the behaviours of getting behind a wheel, and really the human rights of other road users who have a right to be safe from those who may choose to use drugs and then drive.
I was over in Banff only last month at an international road policing conference and I presented on this there. Some of the road policing models in both Canada and America are very different to ours because we have the luxury of a general deterrent model. As I've said, we test 4.5 million people just in Victoria for alcohol, and we have 4.5 million people who are licensed, so we aim for one test per year per driver.
I'm happy to take any questions or I could keep talking, if you like, but perhaps your questions may be more relevant.
Liberal
The Chair Liberal Anthony Housefather
Thank you so much, Mr. Fryer.
We're going to move to questions right now. We are going to start with Mr. Nicholson.