Police. Who are they really helping?

Police brutality in 'ghetto' areas just keeps getting worse. Just about two years ago, one of my brother's close friends, Arturo Cabrales was shot and killed in the 10300 block in Lou Dillon ave. According to the police he ran for a gun but his family had a different story. When police threatened to shoot, he ran inside which caused the police officers to shoot and kill him. Our community wants to end this but it seems to be getting worse. More and more brutality acts against African Americans and Latinos are being committed. Personal experience and other's stories are helping me understand that the police departments are only here to 'protect and serve' themselves. What are your thoughts about these police departments? Helpful or nah? Have you had personal experiences or seen something related to police brutality?