I have one next door.
I told him if he ever looked at my daughter like that again he would come to understand the word "victimized."
We had a registered sex offender two doors down from us at our old house. We learned of it when someone put a printout from the state website in our mailbox. I warned the children to stay away from his house. A few years later, he committed suicide, and although I was sad for him, I'm ashamed to admit my first reaction was relief.