Interpreting scientific evidence isn’t always an easy task: it involves assessing a massive set of studies and sometimes coming up against competing findings. Take the issue of cannabis potency, for example, which is in the news again with the Canadian federal government’s recent anti-cannabis television advertisements. These ads claim that cannabis potency has increased on average by up to 400 per cent from a few decades ago. Unfortunately, the issue is just not that cut and dry. Data from the U.S. government suggests that on average, cannabis potency has increased from about three per cent in the 1980s, to 12 per cent in 2012 — a 300 per cent increase. What about Canadian data? Well, government spokespeople have referred only to U.S. data, so we don’t really know what the situation is in Canada.
Misinformed Cannabis Policies Prevent Access to Life-Saving Treatments
Lost in this debate around potency, though, is a basic but important question. Does increased potency actually have a detrimental effect on the body? Unfortunately, this seems to be another case where the evidence is mixed, at best. In the short term, high-potency cannabis can lead to dangerous levels of intoxication, although without the overdose-type effects of alcohol or opioids like heroin. The impact of long-term use is frustratingly elusive, and scientists who have reviewed the evidence have flatly stated that these concerns over potency are not supported by the science.
Even if we assume increased cannabis potency is problematic, though, what is the best way of controlling it? Between the 1980s and the 2000s, when U.S. cannabis potency increased by about 300 per cent, the U.S. government engaged in a massive global program to reduce cannabis supply. Clearly, it was a failure. In comparison, when a Canadian medical cannabis supplier accidentally released a strain of cannabis with THC levels of 14 per cent earlier this year (it was labeled as nine per cent THC), Health Canada took a simple step: it recalled the product from the market. Just like that, the higher-potency cannabis was off the market, something the U.S. government couldn’t achieve despite investing billions of dollars and deploying the world’s largest counternarcotic force.
We expect our political leaders to build policies based on the evidence so that they are as effective as possible. Drug policies should be no different. Unfortunately, Canada’s current policies on cannabis are based on a misreading of the science. Worse, they are making it harder for people to access life-saving medicine.
For more information on the scientific evidence behind oft-repeated claims about cannabis use and regulation, check out the International Centre for Science in Drug Policy’s latest reports and ongoing campaign for evidence-based cannabis policy. Make sure to sign up for their newsletter so you never miss an update.