Stop unjustified police shootings in four simple steps;
1) Prohibit police departments from investigating themselves and establish independent citizen review boards comprised of public members chosen at random from every group, rotated regularly, limited to one term of service.
2) Take prosecutorial discretion away from District Attorneys. When it has been determined that enough probable cause exists to justify filing criminal charges, those criminal charges must be filed. As it stands now, District Attorneys are loath to bite the hand that feeds them. Without police cooperation, a DA’s career goes nowhere. Biggest conflict of interest I know of.
3) Make the Officer personally liable for their own actions, not the city or the taxpayer. If a cop kills or injures someone, let the family sue that officer personally in court. As it is now, there is no risk for bad behavior because they have immunity, the money doesn’t come out of their own pockets. The homeowners and businesses of that city pay instead.
4) Require all cops that interact with the public to wear body cameras. Require that the audio and video from those cameras be curated in perpetuity by a separate and impartial entity not connected to the department nor the city in any way. Take control of the body cameras out of the hands of the individual officers, as of now they can just turn them off when about to do something dirty.
Institute these steps as policy across the nation and you will see an end to brutality and misconduct, or at the very least a dramatic reduction. Simple, but not easy to accomplish. Police unions will fight to the death and they wield a formidable amount of political power. It can be done however, if enough people care and stand up.
If you really want to get to the heart of the matter, make community policing just that. Require that every qualified person receive academy training and then rotate the responsibility among every citizen. Training could start in high school. Everyone is a cop then. Israel and Switzerland do it, the model is proven.