As an FYI - I support weed being legal.

However, the science is in and has been for some time now, the cut-off point should be 24 and older and not 18 as suggested by the Trudeau Party for adolescences to start smoking weed.

However, if it was 24 plus, then those adolescences who are 15 now, will not vote for the Trudeau Party, or any party that says they have to wait until 24. 

However, smoking under 24 does explain a lot as shown below and why the millennials were voting Liberal.
...
“There is growing evidence that repeated exposure to cannabis that begins during adolescence is associated with a decline in IQ of about 10 points when subjects are tested in adulthood,”

Sanjiv Kumra, an associate professor of psychiatry at the University of Minnesota Medical School who has studied cannabis’ effects in young people.

“This effect is not seen in adult users of cannabis.”