A new study evaluating data collected by the World Health Organization has found that strict drug laws don't do anything to prevent young people from using cannabis.
The study was conducted by University of Kent professor Alex Stevens and looked at data collected from over 100,000 individuals across 38 countries. While many people have argued that loosening cannabis laws will lead to increased use of the substance by young people, Stevens says his research shows there is "no evidence of a link between tougher penalties and lower cannabis use."
"This is useful information for governments as they consider the best way to deal with cannabis," Stevens wrote. "As it is, the harms and costs of imposing criminal convictions on people who use cannabis do not seem to be justified by an effect in reducing cannabis use."
Stevens' study follows an earlier one which used the same data but came to the opposite conclusion. However, he says that the reason the two studies made drastically different findings was because the previous one failed to look at key statistics and "depended on a misinterpretation of the results."
"When taking into account the differences in cannabis use between boys and girls in different countries, and using more of the data, a statistically significant association between policy liberalization and adolescent cannabis use cannot be found," Stevens told The Times.
Advocates of cannabis reform in the UK were quick to add the new study to the growing list of research that suggests prohibition doesn't protect people; it simply subjects them to criminalization.
"Countries that have ended criminal sanctions for possession of drugs have shown they have better health, social and economic outcomes, yet the UK government continues to have an evidence-free approach when it comes to the law around drugs," Niamh Eastwood - Executive Director of Release, the UK's center of expertise on drugs and drug laws - told The Guardian.
Meanwhile, legalizing cannabis may actually reduce the appeal of the substance for some young people, according to Ian Hamilton - a mental health and addictions professor from the University of York.
"For some of them the fact it is illegal will be part of the appeal, so if a country decides to open up access and allow regulated cannabis this may reduce part of the appeal the drug has," said Hamilton, who is not associated with Stevens' study.
Despite his findings, Stevens is hesitant to say that legalization won't result in any increase in youth cannabis consumption.
"The study included countries that had decriminalized cannabis, such as Portugal, but at the time it did not include countries like Uruguay that have legalized sales," explained Stevens. "Wider availability and advertising might affect teenage demand but we just don't know yet."
With that said, there are now two countries—Uruguay and Canada—which have legalized recreational cannabis on a national level and the substance is now legal in ten US states as well as Washington, DC. This means that the next time the WHO collects data on global cannabis consumption, we should get a better picture of what legalization actually does for consumption rates.