Police tend to escalate a situation when things become difficult to manage. In doing so, officers end up using excessive force that usually involves an unnecessary amount of pain and discomfort, sometimes death, often having a group of officers pouncing on a single individual. If police practiced non-violent techniques or used minimal force to successfully detain a criminal, it would perhaps mitigate some of the problems we see today. In addition, more time is spent training in proficiency on weaponry than it is dealing with human beings and a proper reading of given scenarios, perhaps it should be the other way around or equal in time. 

Also, the idea of "innocent until proven guilty" shouldn't mean inhumane behavior towards any POTENTIAL criminal. It's hard to be innocent if you're in cuffs and thrown in a cell, not to mention the influx of emotion after such action. There should be an in-between stage that doesn't involve a cell and improper treatment, and allows the persons involved to calm down and tell their story. 

And finally, Police that have to meet quotas end up giving simple and innocent citizens a hard time, in which they have to spend time and money that they possibly don't have. When officers of the law do not meet that quota, they end up being penalized, via a revoke in vacation days among other things etc. If such a gauge were to be lifted, police would be less inclined to pull people over and bother with petite violations, making the civilian a little more comfortable within their communities and establish a bit of trust within them. In addition to that, Police fear consequence of reporting other officers. They should feel safe when trying to establish a more honest organization that is meant to protect both the communities it serves and the law. This also steps towards a mutual trust between citizens and officers of the law.