Robert D. Hare is a Canadian psychologist best known for his work in the field of criminal psychology and psychopathy. He developed the Hare Psychopathy Checklist, a tool used to assess psychopathic traits in individuals, particularly in criminal populations. His research has significantly influenced the understanding of psychopathy and its implications in criminal behavior. Hare has authored several books and articles on the subject, including Without Conscience, which explores the characteristics of psychopaths and their impact on society. His contributions have made him a prominent figure in psychology, particularly in discussions surrounding mental health and criminal justice.