Having worked and still working in public safety and corrections, if some one breaks into your house, all you need to do is tell them they are trespassing and need to leave. If they don't you can use force to remove them from the property. The law is worded as "enough force as necessary". Which is open to what ever interpretation. Meaning some one walks in unarmed you tell them to leave they don’t, and you shoot them, well you are most likely going to prison.
This is the same as the posted self defense laws, and also defense of property.(again if some one comes at you un armed and you stab them, your not going to have a good time.) That being said, normally a guide line for use of force is: say some one attacks you un armed, you clock them in the face, they drop, you kick them in the head, You're going to jail. You drop them, they get back up, you drop them again, legit. At the second drop I would take it further. Don't go in and beat the **** outa them, but subdue them, if they resist, go ahead and hit em a few more times. Make all attempts to not do grievous harm.
As far as fire arms, in Canada, if you shoot some one in self defense be it a knife or gun against you, what ever, and kill them, at best you are still looking at a manslaughter charge. You will always be facing down some sort of charge no matter what. But remember just because you are charged does not mean you will be convicted, it may be unlikely a jury will convict you. Also ALWAYS COMPLY WITH LAW ENFORCMENT! Talking back or resisting while shouting it was self defense will damage your credibility.
There is so much more to this, and I have done my best to explain things on a simple level. That being said if the situation can be deterred peacefully do so. Also if some one broke into my house, with a gun, i would most likely retaliate with my S.S P226 and fire warning shots(if I can open my safe and throw in a mag fast enough). Most people will be deterred by this. And I would much rather face down a firearms discharge charge, than a manslaughter charge. Either way your life gets f'ed while everything goes through the court system, which any one that has been through it will tell you is a very lengthy process.
And as some else has stated, you may not even get a charge if you incapacitate some one.
Also this is a good guide, and if you coudl quote that to the cops, you will greatly help your situation. Although its your word against some one elses
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