When most people can't afford to go to trial (both financially, and because they'd be insane to not take a plea), the checks and balances of the judiciary are, in practice, only available to a privileged few.
When you piss off a cop, get arrested, and are released a few days later, without any charges, you also have exactly zero recourse through those checks and balances.
When you piss off a cop, and he brutalizes you, you may get some recourse (through a lawsuit, unlikely as your case may be), but it does not serve as a deterrent to subsequent police misbehaviour. (As we have seen over the past summer.)
People sue for unlawful arrest and bad police behavior and win all the time. Check out this YouTube channel dedicated to covering just that... https://youtube.com/c/AuditTheAudit
The bar that needs to be met for proving that you were subjected to an 'unlawful arrest' is so incredibly high, it's farcical. Ten times out of ten, you're better off moving on with your life, and forgetting it ever happened.
Are there a lot of minimum wage, single parent type people that do that?
As an upper-middle-class office worker with flexible hours and cash to spare, even pursuing a small-claims case was a major PITA for me. Took a ton of time, effort, and money.
When you piss off a cop, get arrested, and are released a few days later, without any charges, you also have exactly zero recourse through those checks and balances.
When you piss off a cop, and he brutalizes you, you may get some recourse (through a lawsuit, unlikely as your case may be), but it does not serve as a deterrent to subsequent police misbehaviour. (As we have seen over the past summer.)