I can understand that. In despair, a lot of people in my Brazilian family think like you. But the problem is that this mentality opens a wide space for a whole different class of criminals. And that's what is going on in Rio : small business owners decided to bribe police officers in exchange of security. These corrupt policemen wiped away ordinary criminals but then they just replaced those, became organized crime by themselves, practicing drug traffic, extortion, monopolies in natural gas distribution and all sorts of illegal activities. In Rio they're called militias.
In the end, there's no alternative to the rule of the law. In the long run, a lynch mob mentality will only create bigger problems on the long run.
As soon as you start unpacking why and how you got into an urban war, you'll approach the fussy philosophical questions raised by the human rights crowd.
Just to give you an idea, an acquaintance of mine never knew his grandfather was in a federal prison, he was told it was a secure retirement home. The grandfather's crime was a dirty cop that had literal death squads killing people in cold blood for years and making money off dead dealers. He used the chaos in the streets to line his pockets with money and silence the people who tried to snitch on him.
War is always a good excuse to ignore ethical concerns.
On Both sides
The weapons and the drugs that finance the traffic do not come from the poor communities, the crime in rio is deep within the society killing the poor that is already marginalized it’s not a soluction.
I agree with you on the other side, people with weapons should be treated as the threat that they are, but the public policy should not be just “kill theses guys and we are good”.
However on HN the discourse has the exact opposite bias. People have this idea of morality that's based on their conceptions and not directly on what's happening around them.
How about "people openly flaunting assault weapons"? As someone who lived in Rio most of their life, I think that's a good line to draw. Opinions filled with "human rights" concerns from people far removed are probably ethically and morally correct, which is... cute.
We're fighting an Urban War over here. This is a Concrete Jungle. This is a crazy post-apocalyptic situation to which most people in Rio grew accustomed to while most people outside Rio can barely picture.
As a police officer once told my wife as she was leaving her house in Rocinha and stopped to be patted down and inquired why was she being selected:
– Mam, do you know where you are? You are not in in Los Angeles. You are not in Paris.
My moral qualms went out the window around the same time my grandmother was murdered by being thrown off a bridge in Aterro do Flamengo.