Why did Bryon dislike cops so much?

Byron dislikes the police because of experiences he had with them when he was younger.

I figure it was because of this cop— these two cops— who beat me up once when I was thirteen years old. I had gone to the movies with these other guys— I forget where Mark was —and we drank a fifth of cherry vodka in Coke and got drunk. That stuff tasted terrible, but I was a dumb kid and I drank it just to show I was as super-tuff as the rest of them. When the movie was over and I was staggering around alone on the streets in the dark, these two cops picked me up, drove me out to a hill on the other side of town, slapped me around, and left me there. I never forgot it. It didn't stop me from drinking, but it sure ruined any respect I ever had for cops.