In this article the reliability and usefulness of Hare's Psychopathy Checklist Revised (PCL-R) and the conclusions on basis of the scores are examined. It was concluded that, a) this checklist is a not a reliable tool, b) the conclusions that are linked to these PCL-R scores with regard to the treatability of psychopaths are incorrect, harmful and unethical, c) can easily be misused in legal systems and forensic psychiatric settings to dispose of problematic psychopaths, and d) the diagnostic category psychopathy should be rejected firmly because some items are subjective, vague, judgmental and practically unmeasurable, and the term psychopathy itself seems to be judgmental. Suggestions are made in order to prevent misuse of such assessment and prediction tools.