The laws in western europe (to be more specific: Austria - I don't know that much about Brazilian laws) ensure that only the state has the right (in most cases)

The laws in western europe (to be more specific: Austria - I don't know that much about Brazilian laws) ensure that only the state has the right (in most cases) to use violence and give criminals what they "deserve". It cannot be that a normal person or even worse, a victim, tries bringing justice (or at least what they personally believe to be justice) to criminals (or people they believe to be criminals), because they are not trained policement that know their limits, nor are they usually judges. I am not saying that a normal person should not use self defense, I definitely would, but there are limits to what is considered an appropriate reaction. I cannot kill someone if the person doesn't show aggression towards me or someone else. (a burglar breaking into my home) Likewise I cannot beat someone into unconsciousness if I could have just held that person down until police arrives. What did your friend do to the robber after he disarmed him? Could he just have held him down? What kind of aggression did he use? From your description many things are possible, from slapping him, to breaking his spine and many things in between. The same goes for the policemen. Did they needlessly risk or cause the death of innocent bystanders? That is also something that policemen must consider before they do anything that could start a shooting.