If Canada were to invalidate pattents, they would face sanctions form all WTO member states. You want to talk ‘dealing in bad faith’, that’s a great way to do it.
That said, there’s some issues with things people have said about this proposed pattent invalidation helping the Canadian pharma industry. They could, by all mean, produce all the drugs they want for domestic consumption. But, the minute they export them, they’ll be in violation of those pattents in the importing country–which did not invalidate the pattents.
And, if Canada ever wants to normalize relations with the USA–say once they elect a sane leader–this is a one way poison pill to any productive future relationship. You can’t put that genie back into the bottle.
This proposal is like saying the solution to one side being a jerk is for the other side to be a bigger jerk. Yeah, it might make you feel good, but it’s not going to solve the issue.