Why are black people tragets for police beating?

on oct 30th here in Minneapolis, MN my two sons and their cousins got trageted for police beating and was not doing anything my son had just came out of the stop with his cousin when to minneapolis police officers came up to his car with their guns draw and pull the cousin out of the back set push his head up agest the car and through in the police car the partner went to my sons side of the car and said get the **** out of the car my son said you cops love to mess with people and then the officer open the car door and hit my son in the jay three time while he was still in his set belt snach out of the car and hit again then taze you get the picture.