Whole lotta' armchair QBing here. Might I suggest this isn't as easy on the ground. 

That being said, here is what I see. Many clearly identifiable cops yelling at a man to drop a gun. It looks to me like he had one, but for the sake of argument, let's say he was holding the Good Book after coming from Sunday sermon. The cops still thought it was a gun, he didn't drop it, and was angling to flank the cops who were in a covered position. I wouldn't have liked it, but I would have shot him too. The screaming lady isn't helping. You can't negotiate with a cop who thinks he might be shot.

Of course they restrained him and secured the scene prior to rendering aid. This isn't the movies. Getting shot doesn't mean he is out of the fight. I've seen folks take 7.62 and multiple 5.53 rounds and keep coming. Standard proceedure is to reduce the threat, secure the scene, and call for help before rendering aid.

Maybe a tragic misunderstanding, but like it or not, this is how this has to work.