Because unarmed naked people can't harm anyone, right? Just because he's naked means he can't overpower someone. I remember a few different Cops episodes with naked black guys, and each one required multiple cops just to restrain the guy. One even slipped through over a dozen cops trying to hold him down.

If you weren't there, then you can't judge what happened. There just isn't enough information to make an informed decision one way or the other. That is unless you just like to make assumptions.