They might also have asked why it became illegal in the first place.

That happened in 1923, and if there was any kind of parliamentary debate, historians have been unable to find a record of it.

When Parliament decided to add marijuana to the schedule of proscribed drugs that year, Canada became one of the first countries to make smoking pot illegal. The U.S. didn’t accomplish that until 14 years later, in the midst of the Great Depression.

https://www.cbc.ca/news/health/marijuana-was-criminalized-in-1923-but-why-1.2630436