I know. It's the old story.
The issue is that the Americans might ask you whether or not you've had a criminal record.
However, at customs, they are not necessarily trying to find out whether a person has a criminal record. That is the peculiar thing. They are trying to find out whether that person has used marijuana, because the American do not always see as legal in their country what we see as legal in ours.
We have to tell those Canadians interested in the matter that, although this is an innovation that is more than justified in Canada, it does not guarantee a problem-free open door to the United States, because of the nature of the use.