In an ideal world the police enable us to live in a free society, without the fear of the strong preying on the weak. We do not live in an ideal world, so most police departments fall well short of that goal.
At their worst police prey on the members of society with the weight of the 'justice' system behind them, giving them carte blanche to spread fear and intimidation and levy fines and impose penalties without reprisal. If they are in collusion with the courts they can write your ticket and then the court can enforce it and you have no recourse. Can you imagine how awful it would be to live in a place like that? No? Well if you live int the United States you don't even need a passport because you can find it in Ferguson, Missouri. And New York City. And big and small municipalities all over the country.
The truly damning thing about the Ferguson Report is the institutionalized racism and predatory attitudes of the police and judges and clerks and every single person that worked for the government. Bear in mind that this is just what the Ferguson Report found and could reasonably prove - it is by no means the worst of what they may have heard.
Ferguson PD and local government put their boot on the neck of the populace, every day, for years. This is the courts creating laws to generate revenue and charging the
Imagine what rich white America would do if you rewrote the report and replaced the words "African American" with "jewish". People would flip their shit! As it is, well, there's some outrage, and some of the worst offenders (where 'offender' = repressive, racist government asshole) are going to lose their jobs but on the whole they will go unpunished, retreat to their redoubts, and continue to forward emails about how Barack Obama is the antichrist. To be fair, it's not like they did anything that was against the law.