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What Do We Know About Psychopathy?

Do certain psychological traits predispose people to criminal behavior?

Bernie Madoff

Bernie Madoff was convicted of running a $50 billion Ponzi scheme

Bernie Madoff

Bernie Madoff was convicted of running a $50 billion Ponzi scheme

Bernie Madoff asks "Am I a sociopath?" Psychologists are more likely to use the term psychopath than sociopath, reflecting our interest in the individual mind. What is a psychopath and what do we know about people who do fit this description?

Is there such thing as a criminal mind?

For quite a few decades, the mental health field has attempted to classify and study the personality traits of people most likely to engage in criminal behavior. In other words, they have tried to diagnose the criminal mind. In the DSM-IV and DSM-IV-TR, the official diagnostic system of the American mental health field, the diagnosis of antisocial personality disorder describes people who habitually violate social norms and moral codes.

What is antisocial personality disorder?

People with Antisocial Personality Disorder (ASPD) are characterized by callous and exploitive behavior and by a lack of empathy or remorse. In DSM-IV, a person with this disorder demonstrates a pervasive pattern of disregard for the rights of others as evidenced by at least three of the following criteria: repeatedly engaging in illegal behavior; frequently lying, using aliases or conning others for personal profit; impulsivity and lack of future planning; irritability and aggressiveness; reckless disregard for the safety of self and others; consistent irresponsibility, with repeated failures to sustain employment or fulfill financial obligations; lack of remorse as evident in indifference to or rationalization of hurting, mistreating or stealing from others. This definition has been criticized, however, for being too focused on behavior instead of personality traits and also for requiring evidence of conduct disorder (a childhood variant of ASPD) before the age of 15.

What is psychopathy?

The concept of psychopathy should be distinguished from the DSM-IV concept of antisocial personality disorder. While diagnosis of antisocial personality disorder is heavily dependent on a record of criminal behavior, psychopathy is more geared to the actual personality traits associated with criminal behavior. Such traits include callousness, superficial and shallow emotion, lack of empathy, irresponsibility, lack of remorse or guilt about harming others, and the tendency to exploit, manipulate and engage in predatory behavior towards others. Psychopathic prisoners commit more serious and violent crimes than non-psychopathic prisoners. They are also more likely to recidivate (commit another crime) after they are released from prison. Moreover, psychopaths are more likely to commit premeditated rather than impulsive crimes. In Michael Woodworth and Stephen Porter's 2002 study of 125 prisoners convicted of homicide, the 34 psychopathic prisoners were much more likely than the 91 non-psychopathic prisoners to have committed premeditated murders (93.3% vs. 48.4%).

Men arrested for murder in the 1930's

Accused murderers in the 1930's

How is psychopathy measured?

Men arrested for murder in the 1930's

Accused murderers in the 1930's

The foremost expert on psychopathy today is a psychologist named Robert Hare. He has developed an intensive interview to measure psychopathy named the Hare Psychopathy Checklist. His first version was published in 1980 and the revised version (PCL-R) in 1991. The PCL-R is a 20-item clinical rating scale that is scored based on information from a semi-structured interview and available legal files, medical records and collateral interviews with someone who knows the subject well. Although the maximum possible score is 40, the average scores in both male and female offender populations range from about 22 to 24. Hare uses a cut-off score of 30 to distinguish psychopaths from non-psychopaths. He believes that psychopathy is more of a category than a dimension. This means that someone either is or is not a psychopath. Notably, other researchers disagree and believe that psychopathic traits fall on a continuum.

How common is psychopathy?

Hare estimates that about 50 - 75% of the prison population meet criteria for antisocial personality disorder but only 15-25% exceed the cut-off point for psychopathy. Hare also estimates that psychopaths make up about 1% of the general population. Thus psychopathy appears to be a more severe disorder than antisocial personality disorder but fortunately a less common one.

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Hare, R.D. (2008). "Psychopathy: A Clinical Construct Whose Time Has Come." Current Perspectives in Forensic Psychology and Criminal Behavior, 2nd Ed. Thousand Oaks, CA: Sage Publications.

Hare, R. D. (2003). The Psychopathy Checklist-Revised, 2nd Edition. Toronto: Multi-Health Systems.

Woodworth, M. & Porter, S. (2002). "In Cold Blood: Characteristics of Criminal Homicide as a Function of Psychopathy." Journal of Abnormal Psychology, 111, (3), 436-445.