Many groups like MADD Canada have pushed for a mechanism of roadside testing for drivers suspected of being impaired by drugs. They see the development of these tools as a victory in the battle against impaired driving. But will a marijuana breathalyzer really help anything?
I say no.
When Could Police Use It
One of the most glaring issues that stands in the way of a marijuana breathalyzer is the issue of when police would be entitled to use it. For roadside breathalyzers used in Canada, police have to have a reasonable suspicion there is alcohol in a person's body. This is an issue that has been heavily litigated. But how will police form a reasonable suspicion there is marijuana in a person's body? Sure, in cases where a person admits to smoking recently there might be a basis to believe that. But it isn't as though there is an odour of marijuana on the breath to give the officer the suspicion. An odour in the car means simply that it's either present in the car, was at one time present in the car, was smoked in the car, or was smoked near the car. It doesn't give any reasonable basis to believe there is marijuana in the body of the driver.
What about other symptoms of marijuana consumption? While glassy or bloodshot eyes, pupil abnormalities or reactiveness may be an issue these are as explained by alcohol or other drugs. For a marijuana-specific breathalyzer, the officer would have to have a reasonable belief that marijuana and not alcohol or something else caused the symptoms. It's not something that, in my view, could likely be made out.
Changing the Law
Right now, the law doesn't provide for these types of demands. Officers can make a person do Standardized Field Sobriety tests if they suspect there are drugs in a person's body. But they cannot ask for a marijuana breathalyzer. Which means that the Criminal Code or the provincial Motor Vehicle Act would have to be amended to allow for these demands. Legislative amendments take time. There will be debates, votes, and discussion. It isn't an overnight process.
Once the legislation is passed, assuming it ever is, there is an inevitable constitutional challenge on the horizon. Either the standard for the demand will have to be relaxed (see above) or it will be impossible to meet. And so the Government will not likely be able to rely on the jurisprudence about roadside breathalyzers for alcohol as a basis to support their marijuana breathalyzer demand and search. Meaning that there will be several years of litigation to wade through before there is any certainty about it. As an example of the timeline, BC's Immediate Roadside Prohibition law was first challenged in September, 2010. A decision was made in November, 2011. The matter was not finally settled by the Supreme Court of Canada until October, 2015. And even still, there are issues related to remedy that still have yet to be addressed by the Court of Appeal. Five years, and still no finality.
Approving the Device
Moreover, in order to conduct the search and rely on the device, the Attorney General of Canada or the Lieutenant Governor in Council for British Columbia will have to prescribe devices that can be used for these purposes. This will require testing of the devices by the RCMP Forensic Laboratory in Vancouver, and likely further testing by the Canadian Society of Forensic Sciences Alcohol Test Committee. Who may refuse to do it since they are alcohol-interested. Which means there may need to be a Canadian Society of Forensic Sciences Marijuana Test Committee for this purpose. This will take years.
So I'd estimate that by the time Cannabix actually perfects the device, it will still be at least ten years before Canada or the provinces are in a position to rely on them for any purpose. By then, any savvy competitor (like Intoximeters or CMI) will have copied the technology and there will be a wide market for these devices.
Per Se Limits
We are also hampered in Canada by per se limits. While there are limits in the Criminal Code for alcohol concentration, and lower limits in the Motor Vehicle Act, we have no limits for the concentration of any particular drug in a person's body. And these limits, unlike alcohol, are not practical. Alcohol tends to affect all people in the same way at specific concentrations. There is a wide body of scientific evidence to support the notion that at 100 mg% most people are impaired in their ability to operate a vehicle. But marijuana is a different beast entirely.
I recently spoke with an expert in the field of Standardized Field Sobriety Testing and Drug Recognition Evaluation. He informed me that preliminary testing he has done with marijuana reveals the opposite. People who are chronic users tend to be more impaired without the marijuana. People who are occasional users become impaired more quickly than people who are regular users. In his testing, there is no consistency among a population between the amount of marijuana consumed and the concentration of marijuana and how it leads to impairment.
Similarly, the scientific community has not been able to establish consistent absorption and elimination rates for marijuana among the population. Which means that any per se limit for marijuana will be purely arbitrary. We can see these problems arising recently in Washington and Colorado, where drug-impaired driving is said to be on the rise and police are having a difficult time investigating and proving these cases. Parliament is unlikely to accept an arbitrary per se limit, which means years of scientific research will be necessary to establish this for marijuana.
Other considerations regarding per se limits
The difference between marijuana and alcohol in how it is consumed is also a problem. We are likely to very soon see marijuana legalized for recreational use in Canada. In alcohol-impairment cases a defence that rarely arises is involuntary intoxication. It's not often that people unwittingly drink alcohol to the point of impairment, although it has been known to happen. But if you're at a party or an event where people are smoking marijuana you will ingest that smoke through the very act of breathing the ambient air. How does a person know how much ambient marijuana is too much? How does the Crown prove the marijuana was willingly ingested as opposed to unwittingly so?
There are also many candies, creams, and other products that do not look or taste like they contain THC. I can only imagine the number of unintentional marijuana-impaired cases that will arise once marijuana is legal and these products become more mainstream and widespread. Certainly involuntary impairment will be a defence, but I expect it will be a more prevalent defence and it will gut the strength of any per-se limits in the same way the evidence to the contrary arguments once did with alcohol.
What about a failsafe?
And though I haven't tried them (which is not to say that I'm not very curious), I'm aware that there are many products containing marijuana that do not taste or appear to be THC containing. For example, there are topical creams and lip balms. If a person uses this, but their blood THC concentration is not significantly elevated, can the marijuana device detect the THC in those? Similar to an approved screening device reacting to hand sanitizer? What if marijuana is present in the ambient air, such as fresh marijuana in the car? Will there be ambient fail safeguards? Breathalyzers used for evidentiary purposes have built-in safeguards to present this, but roadside devices do not.
What about people who are sucking on marijuana candies, or who have recently eaten a marijuana-containing product?
How many innocent people will be convicted because of the device's failure to differentiate between THC in the bloodstream versus that from some other source?
All in all, I don't see a marijuana breathalyzer as a reality in Canada for at least a decade. And even then, I doubt it will withstand constitutional challenges. But I could be wrong. And if I am, then I'll learn as much about this device as I know about breath testing equipment in order to challenge the validity of the results.