Can you go to jail for excessive force on a child molester/killer when he is "in the act"?

There SHOULDN'T be any laws against cutting this SBAGS nuts off, but unfortunately, you might have a problem. Once you bound him and called the cops, you should've left him alone. Think up a good defense. Tell them he got into your head by saying things to you or threating you. Now you gotta make it look like YOU'RE a little wrong in the head. Who knows though. HTH!