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Psychopathy: A Clinical Diagnosis

The most dangerous antisocial personality disorder.

Public Domain
Eyes of a psychopath
Source: Public Domain

Psychopathy is an antisocial personality disorder that is highly correlated with crime and violence. The concept of psychopathy has been known for centuries but only in recent years has there been considerable research attention paid. In particular, Robert Hare, a prominent researcher in the field of criminal psychology, has led research efforts to develop a series of assessment tools to evaluate the personality traits and behaviors attributable to psychopaths.

Dr. Hare and his associates developed the Psychopathy Check List Revised (PCL-R) and its derivatives which provide a clinical assessment of the degree of psychopathy that an individual possesses (1).

Based on 40 years of intensive empirical research, the PCL-R has been established as a powerful tool for the assessment of this serious and dangerous personality disorder. Specific scoring criteria rate twenty separate items on a three-point scale (0, 1, 2) to determine the extent to which they apply to a given individual.

The instruments developed by Dr. Hare and his colleagues attempt to measure a distinct cluster of personality traits and socially deviant behaviors which fall into four factors: interpersonal, affective, lifestyle and antisocial.

The interpersonal traits include glibness, superficial charm, grandiosity, pathological lying and manipulation of others. The affective traits include a lack of remorse and/or guilt, shallow affect, lack of empathy and failure to accept responsibility. The lifestyle behaviors include stimulation-seeking behavior, impulsivity, irresponsibility, parasitic orientation and a lack of realistic life goals. Antisocial behaviors include poor behavioral controls, early childhood behavior problems, juvenile delinquency, revocation of conditional release and committing a variety of crimes.

An individual who possesses all of the interpersonal, affective, lifestyle and antisocial personality traits measured by PCL-R is considered a psychopath. A clinical designation of psychopathy in the PCL-R test is based on a lifetime pattern of psychopathic behavior.

The results to date suggest that psychopathy is a continuum ranging from those who possess all of the traits and score highly on them to those who also have the traits but score lower on them. This PCL-R allows for a maximum overall score of 40. A minimum score of 30 is required in order to designate someone as a psychopath.

The scores for those who are psychopaths vary greatly, revealing that very high to low levels of the condition exist among those who have it. Non-criminal psychopaths generally score in the lower range (close to thirty) while criminal psychopaths, especially rapists and murderers, tend to score in the highest range (close to forty).

No two psychopaths score exactly the same on the test. The average non-psychopath will score around five or six on the PCL-R test.

Dr. Hare and other experts, including forensic psychologists and FBI profilers, consider psychopathy to be the most important forensic concept of the early twenty-first century. Because of its relevance to law enforcement, corrections, the courts and related fields, the need to understand psychopathy cannot be overstated.

This includes knowing how to identify psychopaths, the damage they can cause and how to deal with them more effectively. For example, understanding the personality and behavioral traits of psychopaths allow authorities to design interviewing and interrogation strategies that are more likely to be effective when dealing with them.

Psychopaths’ manipulative nature and skill in the art of deception can make it difficult for law enforcement officers to obtain accurate information from them unless the interviewer has been trained in special techniques for questioning such individuals. Professionals who work in the criminal justice system must understand psychopathy and its implications because they will definitely encounter psychopaths in their work.

Approximately one-third of all prison inmates who are considered to be “antisocial personality disordered” meet the criteria of severe psychopathy specified in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).

For the very first time, the APA recognized psychopathy as a “specifier” of clinical antisocial personality disorder in the DSM-5, although psychopathy is still not an officially accepted clinical diagnosis. The recognition of psychopathy as a specifier of clinical ASPD by the APA follows nearly fifty years of research and debate.

It is significant because the DSM-5 serves as a universal authority for the diagnosis of psychiatric disorders. The DSM-5 was published on May 18, 2013, superseding the DSM-IV-TR, which was published in 2000.

I examine the public’s intense fascination with notorious, psychopathic and deadly predators in my work as criminologist and in my book Why We Love Serial Killers: The Curious Appeal of the World's Most Savage Murderers. Follow me @DocBonn on Twitter and visit my website


1) Hare, R. D. and Neumann, C. S. 2008. “Psychopathy as a clinical and empirical construct.” Annual Review of Clinical Psychology, 4, pp. 217-246.

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