"Police officers are just doing their jobs." That's the common defense I usually hear for cops. Nazi storm troopers were just doing their jobs too. At least they had some kind of goal they were trying to achieve. Police are just trying to feed their own egos.
You have to ask yourself, "Why does one become a police officer?" Do they want to help others? If that was the case, he would have become a paramedic, or a firefighter, or maybe even have joined the Peace Corps. An individual becomes a police officer to have power over others. Their whole lives they felt insignificant and found the one job they are capable of doing to have power over others. If they had the skills and mental stability to get a better job they would.
Why do we as a society allow sociopaths to be the enforcers of justice? If the people protecting our streets aren't mentally sound, how can the streets ever be safe? How can we as a country entrust our freedom to people who are only out for themselves?