An example situation might be a person who sees some neighbor waving a gun around and generally being pretty dangerous. That person should call the police, but since that person likes to smoke pot every once in awhile they will probably not call the police out of fear that they will end up who one being harassed and treated as a criminal. The police and DAs have made it such that it is in everyone's interest to never speak to the police, and that is how policing fails.
Admittedly not all police officers are like I describe above, but since you'll never know who you will interact with you have to assume they are one of the bad ones. I once had a police officer acquaintance and even he would tell me stories how he would never want to be pulled over by some of the guys he worked with.
Finally, I'm not sure how society comes back from this mistrust. Once trust is broken it is so hard to regain. Body cameras can help, but then you see the above where they are turned off.
This black-and-white view of policing ends up getting a lot of citizens killed. Police officers often end up getting called out to fill the gap in social services, so why not allocate funds to those programs to help people out of poverty? I mean, I know the reasons (police unions and the prison-industrial complex) but it would make more sense than making the police do this crap.
Right now, the police have to act as social workers. When your social worker carries a gun, anything they do to help you sounds more like a command than advice (and the police often confuse the two as well, since maintaining a sense of control is rule #1 of modern policing).
Myself, I don’t fuck with the police. I don’t volunteer information to them either; I don’t trust the police to be good at their job, so anything you say will only serve to get you in more trouble. And I grew up as an upper-middle class privileged white kid.
I think what a lot of people would like is more policing but less aggressive policing.
Such as the ability to call the police for minor crime like broken windows and know the police aren't going to shoot someone dead. e.g http://www.telegraph.co.uk/news/2017/07/17/australian-woman-... (but there have been a number of other examples, especially involving non-white people)
"Minneapolis police are investigating, but their work has been hampered because the officers’ body cameras were switched off. The police department said the squad car's camera also failed to capture the incident."
How convenient.