What more is there to say?
What are needed are well screened police candidates, meaning psychological screening to weed out the sociopaths and psychopaths. After that, when you’ve found the proper kinds of candidates for policing then you train them properly and drum into their heads that ultimately they are there to protect the people and their Constitutional Rights and most importantly to always live by the oath that they take. When you’ve done that properly you will have the kind of police force that will stand by the people.
Yeah huh. We need to bell the cat.
https://en.wikipedia.org/wiki/Belling_the_Cat
What more is there to say?