this is of course excessive, but
it's fucking stupid to corner a police officer and attack him. and crazy people will always be causing tragic situations.
just from that article you can see the guy had a previous experience of having to shoot someone to prevent a stabbing death. maybe it was like a flashback for him, in which case, he probably wasn't fit for duty.
From what I read, the police officer did not prevent a stabbing or death the last time he shot someone, he simply killed the murderer. Don't know the details though, so I shouldn't be too skeptical. But does seem like there is evidence to suggest this guy is trigger happy.
Also, mentally challenged people don't cause tragic situations. Their carers should be aware of the situation and be able to take appropriate actions. When you know a dude in a wheel chair is going through something, you don't go into a small room and get cornered. That's fucking retarded. The mentally challenged dude in a wheelchair didn't cause this (his actions should of been expected and accounted for), the retarded police officer(s) did.
Another thing, to say that the dude in the wheelchair "attacked" the police officer seems silly. He was waving a pen for goodness sake. If you are cornered by the man, you would think you could see the difference between a pen and a knife. If you can't, he probably isn't close enough to be deemed to have cornered you. Doesn't sound like he "attacked" the police to me. But hey, this is just me being skeptical again.
Anyway, even if the guy in the wheelchair did attack the police, as if two police officers could not physically restrain a double amputee with a pen/knife. Seriously? I think that this is why guns are dumb, it gives people the power to do stupid shit. If the police did not have a gun, worst thing that would have happened is that he got tasered or maybe a dislocated shoulder. As it is, he got a oxet.
It seems obvious to me that someone like this may not follow instructions, which is not the wisest thing to do. But why did the police think they were there? The dude was clearly enraged. Do you expect someone like that to follow your instructions and act in a nice way. Be prepared, man.
EDIT: Just to be clear, I didn't think that this is exactly what you were saying, llama (even though I quoted you). I was just venting some more.