It’s not always practical to avoid certain locales. Given a “bad” police department, you could end up being assaulted or killed as a mere passer-by. Thus the need for scrutiny from the public, to get rid of the bad apples. Everyone can be affected, not just people who choose to live or work somewhere.
Read up on the poor guy from India who was visiting his son in Alabama, and got his neck broken for being the wrong color and walking on the street. Fortunately, the local police chief manned up and disavowed the actions of his officer. But public scrutiny and film evidence can serve to root out bad apples BEFORE they kill or maim someone.
