I am not a doctor but from what I understand :
Pedophiles NEVER stop chasing - no matter their age, whether it is 20 or 80.
I read a study that said (paraphrasing), "A non pedophile rapist will stop being a threat to women once his testosterone / sex drive drops in his mid to late 40's - keeping them in jail after that age is a waste of resources because they will likely NOT reoffend. For some unknown reason, Pedophiles NEVER have that drop and need to remain in jail for life."
Let's hope R Kelly and Jeff Epstein spend the rest of their lives in jail!