" Justice departments and parole boards all over the world have accepted his contention that psychopaths are quite simply incurable and everyone should concentrate their energies instead on learning how to root them out using his PCL-R Checklist, which he has spent a lifetime refining. His was not the only psychopath checklist around, but it was by far the most extensively used. "

― Jon Ronson , The Psychopath Test: A Journey Through the Madness Industry