Back to the original post ...

You can buy bear spray at most outdoors retailers in Canada. IIRC you have to fill in a form. It's regulated under the Pesticides Act.

Carrying it in an urban area is pretty dicey, since you don't really have a valid reason to have it with you. If you're nightclubbing, forget it. If it's in your car and you're returning from the wilds, no problem. I believe the police will make a judgement call based on the context.

If you use it against a human being you will have a lot of explaining to do.

If you use it as a weapon, you will be charged accordingly under the Criminal Code.