I know my opinions sound very cold hearted.... but bear with me, none of us were there to say exactly what happened and how it looked.
But the cop said he could not see what was in the mans hand... regardless of how close it was, maybe it was dark, maybe it was not so obvious it was a pen. The point of the story is that the cops felt threatened.
Sure if they knew it was a pen and still shot the guy regardless then that would be a dick move and completely unjustified. But if they genuinely believed their life was in danger then i really cant blame them for what they did. You all have to remember the situation could have been very heated, everyone is on edge, everyone is in a panic, everyone is yelling, this guy is being hostile and trying to stab a cop with an unidentified object (according to the cop).
Before you guys jump on me for sounding cold hearted , believe me i sympathize for this disabled man so much, my brother is handicapped and mentally disabled and i can see him maybe not able to control himself or his actions in stressful situations, so a scenario like that is my biggest fear regarding my brother.... but im looking at it from the other perspective.
If the cops really didnt know what was in his hands then it was a hostile situation and they acted by the book.
But if they did know it was a pen and still shot the guy, then obviously i would say they were out of line.