I think the kid should be referred to a psychologist and be mentally evaluated to ensure that this isn't the sign of more serious issues which could lead to violence against other people. As far as punishment, I don't think this kid deserves prison time. As much as I like cats, it was still just an animal. The life of an animal isn't worth that of a person, and not 15 years of a person's life. He already has to live with everybody else knowing what he did. Short of leaving the state and changing his name or identity, this guy is already labeled as a cat rapist.