Disrespecting authority

As I watched the video of the cop knocking down that teenage girl and then drawing his gun, I felt very uncomfortable. I sometimes sub teach at a school where they send students who have problems with authority. I had been there a couple of dozen times without incident but my last time there things changed. One of the students, a 14 year old male, said some things about my wife in the most vulgar of terms and I reacted by saying some vulgar things back. It was then that I realized that I was not properly trained to sub at this school and I will not be going back. The cop realized the same thing when he saw the video and he chose to resign. In my own way, I know how he felt. I am concerned about the students in this school as they have no respect for the authority of the teacher and this will likely carry over to law enforcement officials when they are older and out of school. When these students disrespect a teacher the punishment is one hour in a room by themselves. Will they learn from this that the penalty for disrespecting authority figures is a minor inconvenience? Will they one day be on a youtube video?