I have not personally witnessed police brutality, misconduct, or abuse of power but I do believe it exists. Although cell phone videos and police body cameras can not capture the whole story, I think it is hard to dispute that some police act inappropriately. During the course of investigations, some police officers have admitted that their police chiefs have encouraged police misconduct, especially if it leads to an arrest.
I believe there is abuse of power in every profession and law enforcement is not different. Not all police officers abuse their power, but I think it is important to hold officers accountable when they do.