Some of you guys have no idea how ineffective tasers actually are and it shows. There is zero guarantee that a taser even makes proper contact to do anything let alone actually incapacitate someone, which even with proper contact is still a crap shoot. It sucks that he had to shoot, but when someone is coming at you with a deadly weapon, particularly when they've already been non-compliant or combative, you can't ever be sure of their intentions. When you're talking about a person with dementia, ideally it's not even the police responding to that call, but I'm assuming the knife was mentioned on the 911 call, which basically guarantees that the police would show up even if we reformed the way we dealt with emergency mental health calls.