Suggestion - gather/keep as much evidence of what's going on as you can. Look up your provincial Mental Health Act for what "Forms" apply to private citizens requesting examination by a physician and swear the application before a magistrate - if they feel it's legit, a warrant will be issued for detention under the MHA and the person would be taken to an ER for examination +/- referral for formal psychiatric examination/hold. If the person is very fucked up, especially not looking after themselves and becoming a potential threat to others around, it may get them the help they need.
Example - S10(1) Manitoba Mental Health Act, which would lead to a Form 2 here.
C.C.S.M. c. M110
Good advice. Any provincial mental health act that I’ve looked at has similar provisions. You can bring information to a Justice of the Peace, and, if the JO is satisfied that a person, due to mental illness, is a real risk to themselves or others, can authorize police to apprehend them for examination.
‘Crazy neighbour’ calls are some of the most frustrating, because yeah, often it’s short of being something we can effectively act on.
Regarding self defense, the law does allow it, including reasonable force. See s. 34 Criminal Code. Same for defense of property under S. 35. But, ‘reasonable force’ is meaningful. You pull a gun on someone for an attempt to steal property, you’ve now escalated from property crime to threat of death or grievous bodily harm.
Citizen’s arrest is s. 494. You can arrest someone found committing an indictable offense; I won’t parse what indictable means, but any crime of violence to a person, or a mischief (damaging property) or theft in progress will meet that. Again, Force used must be reasonable.
Point a gun at someone for stealing something: no. Tackle and restrain someone committing assault or smashing something up, yes.
If you feel in danger to the point where you access a weapon to defend yourself, you must be able to reasonably articulate why you fear death or similar injury. We don’t have ‘stand your ground’ laws; if you can reasonably retreat to safety, you’re at less legal risk.
But, if you’re genuinely in serious danger and don’t have a reasonable way out in the totality of the circumstances, the law absolutely does allow you to use reasonably necessary force. I think we’ve seen crown and police make progress in their understanding of this in recent years since the Ian Thompson case.