Canada legalised recreational marijuana this week, so should everybody else. While it is sensible to approach mind-altering substances with caution, there is now quite a lot of data on the impact of legalising marijuana. Despite individual problems, and varied approaches to legalised cannabis, in aggregate the data shows change for the better.
In the United States, recreational marijuana is legal in nine of the 50 states, and medicinal use allowed in 29 states. My home state, Michigan, could be the tenth after a referendum on whether to legalise recreational marijuana this November (medical cannabis is already legal). In 2012, the U.S. states of Washington and Colorado became the first to legalise marijuana for recreational use. That means there is now five years of data on what happened.
What does it show?