One of the biggest issues surrounding cannabis and any changes to the law governing it is that of driving under the influence. It is often cited as a reason against changing the law, but people seem to conveniently forget that prohibition does little to stop this. People are already driving around under the influence of cannabis.
The Cannabist, the site the award-winning Denver Post set up after legalisation in Colorado, recently reported on a start up called Hound Labs who have created a marijuana breathalyzer. This is a new way of testing for cannabis use by drivers, which is usually detected by either saliva or a field sobriety test. The article states:
“Technology already exists to test for THC — the psychoactive ingredient in marijuana — in users’ blood, saliva and urine. But the chemical can remain in those bodily fluids for days or weeks after smoking or ingesting marijuana, meaning a user risks being wrongfully accused of DUI even if he or she is no longer under the influence of the drug.”
Therein, lies the rub. Current testing regimes can and do provide false positives – people who have cannabis in their bloodstream but who are not impaired. Colorado, for example has set the legal limit for THC at 5ng (nanograms) per litre of blood. Problem is, a regular smoker can always have this amount of THC in the blood, regardless of whether they have smoked in the last few hours or not. This article by the Associated Press provides a good overview of the issues.
“There is understandably a strong desire by both lawmakers and the public to create legal limits for marijuana impairment in the same manner we do alcohol,” said Marshall Doney, AAA’s president and CEO. “In the case of marijuana, this approach is flawed and not supported by scientific research.”
New Zealand police still currently use field sobriety tests as their major way of detecting cannabis impairment. However, this is set to change with the introduction of saliva testing. These saliva tests can detect cannabis up to 12 hours after use, long after any impairment has dissipated, and have been challenged successfully in court. And this article from The Canberra Times about a motorcyclist being wrongfully charged for drug driving after a crash is a good example of the negative externalities that drug prohibition can cause.
Hound Labs breathalyzer model may be the answer. They claim that it can detect cannabis, whether smoked or ingested, on the breath, for just a few hours after use. This could help put an end to the situation where people are arrested on drug driving charges not for being impaired but for simply having cannabis in their system. As one of their investors states:
“Groundbreaking science is necessary to make an accurate measurement of recently used cannabis, and Hound Labs is uniquely positioned to deliver a solution to the market that respects the needs of the enforcement community as well as the rights of legitimate cannabis users.”
‘Legitimate’ in this case being California, the world’s sixth largest economy, which legalised cannabis at the otherwise unfortunate 2016 U.S. election.
Prohibiting cannabis has helped create this situation. Being illegal, legitimate research into how to test its level of impairment has been nearly completely stymied, and that has created a flawed method of testing that creates unfairness and has left countries like New Zealand unsafe. We see this problem with research in the medicinal use of cannabis and in understanding its negative health impacts also. It is only now that legalisation is spreading that companies are really able to work on technologies that accurately measure THC levels.