It's not just the police. How could such a corrupt police exist without corrupt superiors higher up in the government? Fear of governments is justified, they're the most powerful entity in our world. They can get away with murder.
The US is not Iceland, a simple fix that would just make people trust the police is impossible. Also as an aside, the police isn't your only problem. Tesla, Google & co are paving the way normalizing these mobile surveillance units. We'll have millions of them driving around everywhere with HD cameras, microphones, in some cases even LiDAR and radar. Recording constantly. Of course there's a bit of an issue if you are not a fan of mass surveillance. Even if corporations are the only ones in charge of that data. I know for example that the Tesla video feed can be accessed online, because owners can remotely view it with their app. And if they can do this, so can others in theory. All you need is a bug or Tesla servers getting hacked.