If it weren't a crime in Canada, if Bill C-45 passes, after July 2018 or whenever it passes it's no longer a crime in Canada to possess 30 grams of cannabis. If you have an American who was convicted in the past of possessing under 30 grams of cannabis, that would no longer be a crime in Canada. Would that be a barrier to them entering Canada at that point, it no longer being a crime here? It would still show up on their criminal record, right?
On September 11th, 2017. See this statement in context.