This is very true and I appreciate where you're coming from, I was just trying to make a more general point (hence my mention of the Brazilian guy too) not defend this particular bloke. We all know that if you play with fire, you may well explode.
I'd like to think you'd have to have a gun to be shot by the cops. As you say, he threw it away. If a soldier shot another soldier who threw down his weapon, that wouldn't be "acceptable" either.
Anyway, I'm not defending the man, I just get the fear when we have armed police shooting someone unarmed and apparently no one has done anything incorrectly procedurally, I think it could be a slippery slope before we possibly drift too far.