You use democracy.
In my town, there was nearly universal support for reducing police budgets among citizens. The budget went up by millions.
How, concretely, should I use democracy to address that?
Not the idealized model of democracy where laws that the majority of citizens want get passed, and where if everyone wishes for a law hard enough it happens, but the reality of democracy, where eyeballs cost millions of dollars, and politicians need money and voting blocks to stay in power.
I'd recommend The Dictator's Handbook to understand why that won't work, but you don't seem like the sort to read books. Rules for Rulers is a nice summary:
That's obnoxious, and you know it. I have hundreds of books that I have read in my home, although they probably overlap little with your collection.
Obnoxious is injecting 3-word snide comments when people want to have serious discussions about governance and corruption. If you have something serious to say, please contribute. I'm serious about that -- different points of view are good. If you don't have something to contribute, and you just want to make a douche of yourself, you can expect people to respond in kind.
The real answer is you use politics. Elections are sometimes part of that process, but there are countless times that more was needed. What we see is a political act by people driven to desperation by the failure of electoralism.
If they don't like something about the job conditions, they can vote democratically to change it.
I can't form a tax union and negotiate with the government, why should they be able to?
I don't think anyone is arguing there shouldn't be police unions. However, those should be reformed as open and transparent organizations which support for law-and-order, good working conditions for police officers, and similar.
Those should not be secretive organizations which support police violence, racism, protect bad cops, and sometimes engage in organized crime.