A 2017 study found that certain crimes were reduced in Washington following the legalization of recreational marijuana. The study also found evidence that legalization reduced the use of other drugs, as well as both ordinary and binge alcohol consumption. Another study, from 2014, looked at the relationship between the legalization of medical marijuana in the U.S. and crime rates, and concluded that legalization did not result in an increase in crime. Instead, the study found, legalization “…may be correlated with a reduction in homicide and assault rates…”

Cannabis was outlawed by Parliament in 1923. But a 2002 report by the Senate Special Committee on Illegal Drugs notes that the decision was made without discussion or justification of any kind. In fact, many members of Parliament did not even know what cannabis was or what its effects might be. The report adds that early drug legislation was largely based on “moral panic, racist sentiment and a notorious absence of debate.”

For decades, cannabis use has been unfairly associated with immorality, laziness and crime. The result is a lingering negative stigma that is felt even by those who have been prescribed cannabis for therapeutic purposes. But public opinion is shifting. A 2017 survey by the Government of Canada found that a majority of Canadians believe that cannabis use is socially acceptable.