Canadian Bill C26 Self-defence against unprovoked assault 34. (1) Every one who is unlawfully assaulted without having provoked the assault is justified in repelling force by force if the force he uses is not intended to cause death or grievous bodily harm and is no more than is necessary to enable him to defend himself.
I read a story about some man swatting at a Raccoon with a broom that almost got 2 years in prison. That's more time than what a rapist or child molester might spend behind bars. There was another story about a Chinese corner store owner who apprehended a thief who had been stealing from him regularly and almost went to prison for it. It's scary proposition when it comes to defending yourself. If you cause any harm to the assailant you will be prosecuted. The law in Canada typically favors the criminal.