I haven’t ever had many interactions with police but those few I have had did not include any inappropriate behavior. Similarly I haven’t ever lived anywhere where the police were viewed negatively. When I lived in MA and had applied for a concealed carry license, the Police Chief saw me one day and stopped to apologize for my application having gotten delayed. Last winter on a bitterly cold night my wife was down in our old town in MA and her car broke down. A cop came and offered to help. Her car started up again and he offered to follow her to her destination to make sure she was OK. Last year she was in Albuquerque, NM with a friend and stopped to shop someplace close to the store’s closing time. When they were getting back in the car and taking their time arranging packages and talking up a storm, a cop stopped to make sure they were OK and warned them the neighborhood they were in wasn’t safe at night. My take is that most police are just doing the best they can and that when you are polite and respectful to them they will be polite and respectful in return. No different than anyone else you interact with. All that said, I know there are a-holes, power-hungry, and just plain corrupt people on police forces and I think all police should wear cameras to record interactions. Those that turn the cameras off or abuse their power should be criminally charged, but I for one will gladly take my chances with the police over gangs.
I know that the larger the setting the more difficult it is to have any impact on govt but people in communities where the police are out of control or where civil asset forfeiture or the issuance of civil citations is out of control, people can run candidates for office who will change it. The old maxim of the squeaky wheel gets the grease comes to mind. Blacks, Muslims, and others are using that tactic in cities and towns across the nation and winning many battles as a result.