Defining the Psychopath


What is a Psychopath?

Psychopathy is a personality disorder characterized by a constellation of affective, interpersonal, lifestyle and antisocial features whose antecedents can be identified in a subgroup of young people showing severe antisocial behavior.

Through the early 20th century the term psychopath and other terms such as ‘constitutional (inborn) psychopaths’ or ‘psychopathic personalities’, were used broadly to cover individuals who violated legal or moral expectations or was considered inherently socially undesirable in some way.

“Psychopathy is a condition that causes people to do things that reduce our compassion for them, and so there’s a resistance to funding and treating it.”

Abigail Marsh, PhD – psychologist and neuroscientist

Prevalence of Psychopathy

About 1.2% of the United States adult men and 0.3% to 0.7% of the United States adult women are considered to have clinically significant levels of psychopathic traits.

Those numbers rise exponentially in prison, where 15% to 25% of inmates show these characteristics.

Psychopathy spans across socioeconomic status, race, gender, and culture, and those who score high on psychopathy scales range from high-functioning executives to prison inmates to people whose psychopathic symptoms may reflect difficult life circumstances more than anything else.

History of the Term and Defining It

In the mid-20th century, American psychiatrist Hervey M. Cleckley, published The Mask of Sanity in 1941 and is considered a seminal work which provided  a vivid series of case studies of individuals described as psychopaths. Cleckley proposed 16 characteristics of psychopathy, derived mainly from his work with male psychiatric patients in a locked institution. This marked the start in America of the current clinical conception of psychopathy as a particular type of antisocial, emotionless, and criminal character.

The first version of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM) in 1952 did not use the term psychopathy as a diagnosis, but “sociopathic personality disturbance.” There were four subtypes or also called reactions:

  1. Antisocial: Included individuals who were chronically in trouble and did not appear to change as a result of experience or punishment. Also described as callous and lacking responsibility.
  2. Dyssocial: Included individuals who disregarded societal rules, but were capable of strong loyalties to others or groups.

The other two subtypes were labeled as sexual and addiction. Between the release of the DSM-I and the DSM-III, researchers such as Robert Hare and Cleckley continued to study the concept of psychopaths. Robert Hare published a book in 1970 summarizing research on psychopathy and began to develop the Psychopathy Checklist, which is widely used today. A DSM-III task force developed the diagnosis of antisocial personality disorder and published this disorder in the DSM in 1980.

Following some criticism over the lack of psychological criteria in the DSM, further studies were conducted leading up the DSM-IV in 1994 and some personality criteria were included as “associated features” which were outlined in the text.

The DSM-5 published in 2013, has criteria for an overall diagnosis of Antisocial Personality Disorder similar to DSM-IV, still noting that it has also been known as psychopathy or sociopathy. In an alternative model suggested at the end of the manual, there is an optional specifier for “psychopathic features” – where there is a lack of anxiety/fear accompanied by a bold and efficacious interpersonal style.

Signs of a Psychopath

As described above, Robert Hare developed the Psychopathy Checklist. This checklist consists of a 22-item checklist of perceived personality traits and observable behaviors. Some of these traits consist of lack of empathy, pathological lying, and impulsivity. Each item is scored on a three-point scale, based on whether the item does not apply (0), applies to a certain extent (1), or fully applies (2) to the individual. The highest score a person can receive is 44. The score to be deemed a clinically a psychopath is a score of 30 or higher.  Below is a list of characteristics indicated on the checklist:

  • Glibness/superficial charm
  • Grandiose sense of self-worth
  • Need for stimulation/proneness to boredom
  • Pathological lying
  • Conning/manipulative
  • Lack of remorse or guilt
  • Shallow affect (i.e., reduced emotional responses)
  • Callous/lack of empathy
  • Parasitic lifestyle
  • Poor behavioral controls
  • Promiscuous sexual behavior
  • Early behavioral problems
  • Lack of realistic, long-term goals
  • Impulsivity
  • Irresponsibility
  • Failure to accept responsibility for one’s own actions
  • Many short-term marital relationships
  • Juvenile delinquency
  • Revocation of conditional release (from prison)
  • Criminal versatility (i.e., commits diverse types of crimes)

What Drives Psychopathy?

Research suggests that like other personality traits, psychopathy traits are heavily influenced by genetics and non-genetic factors, such as environment and social factors.

Early Warning Signs

Moreover, studies show that early warning signs of psychopathy may be present in children. For example, children with psychopathic traits are more likely to demonstrate deficient emotional responding to fear and distress in others as well as more severe and planned aggression. These young children are also more likely to continue showing aggressive and antisocial behavior as adults.

The Brain and Psychopathy

The brain also plays a role in psychopathy. Some findings include the amygdala, which is an important emotion processing structure in the brain is smaller in individuals with psychopathy. Further, individuals with psychopathy show reduced activity in the amygdala and greater neural responsiveness in regions associated with reward-processing and cognitive control when performing tasks involving moral processing, decision-making, and reward. This suggests the neural processes that support moral evaluations in individuals with psychopathy somehow differ from those of typical developing individuals.

Psychopathy and Violence

In movies and television shows, psychopathy may appear synonymous with “criminal” or “killer,” but the reality of psychopathy is more complicated.

Ted Bundy was a 1970s serial murderer, rapist and necrophiliac. He was executed in Florida’s electric chair in 1989. His case has since inspired multiple novels and films about serial killers. There have indeed been associations between psychopathy scores and violent behavior, as well as other forms of criminality. Traits such as impulsiveness, tending to placate blame, and lack of empathy may make an individual with psychopathy more inclined than other individuals to cross moral and ethical boundaries and engage in violent behavior. However, not all psychopaths are killers and a number of them are not even criminals.

Are Psychopaths Violent?

There is not an exact statistical number on how many psychopaths commit severe acts of violence, such as murder. However, according to a study in 2018 (Fox & Felisi, 2018), which concluded the average Psychopathy Checklist score on someone who had committed murder was 21.1 (out of the highest score 44), with scores ranging from 9.4 to 31.5. Overall, using a cut off score of 25, 34.4% would be diagnosed as psychopaths. They established that there is a strong link between psychopathy and homicide, and that psychopathic traits are “a significant risk factor for lethal violence.”

Moreover, “as the homicide type became more violent, extreme, or horrific, the relationship between psychopathy and the homicide sub-type became stronger.” Thus, while not all murderers are psychopaths and not all psychopaths are murderers, psychopaths commit a disproportionate number of murders.

Ted Bundy

Treatment Options

Treatment for individuals with psychopathy has not been easy or very successful. Studies have shown that the behaviors of a psychopath do not change in response to psychoanalysis, group therapy, or client-centered therapy. Some research indicates that therapy is counterintuitive and not recommended for individuals with psychopathy or antisocial traits. 

Research has focused on identifying warning signs of psychopathic traits in young children and providing early interventions to halt the development of psychopathy. A primary intervention is behavioral parent training. This type of training is geared toward children who have conduct disorder. Children with conduct disorder have traits such as a lack of guilt, general lack of emotional expression, and a callous lack of empathy. 

For individuals in the teenage years who exhibit psychopathic traits, group treatment tends to be the approach.  A study by Caldwell and colleagues (2007) showed adolescents who rated high in psychopathic features showed improvement following a forensic inpatient treatment, which emphasized the development of appropriate interpersonal skills and relationships.  

Overall, there is not a designated treatment of psychopathy. As noted earlier, many studies and researchers indicated there is no successful treatment for psychopathy. Treatment interventions and approaches appear to be geared at early intervention of maladaptive behaviors.


Arrigo, B. A. (1 June 2001). “The Confusion Over Psychopathy (I): Historical Considerations” International Journal of Offender Therapy and Comparative Criminology. 45 (3): 325–344. doi:10.1177/0306624X01453005. S2CID 145400985.

Burton, B., & Saleh, F. M., Psychiatric Times, Vol. 37, No. 10, 2020

Caldwell, M. F., McCormick, D. J., Umstead, D., & Van Rybroek, G. J. (2007). Evidence of Treatment Progress and Therapeutic Outcomes Among Adolescents With Psychopathic Features. Criminal Justice and Behavior, 34(5), 573–587.

Cleckley, H. The Mask of Sanity: An attempt to clarify some issues about the so-called psychopathic personality 5th edition, 1988. The DSM-IV Personality Disorders Edited by W. John Livesley,

Coolidge, Frederick L.; Segal, Daniel L. (1998). “Evolution of personality disorder diagnosis in the Diagnostic and statistical manual of mental disorders.”  Clinical Psychology Review. 18 (5): 585–599. doi:10.1016/s0272-7358(98)00002-6. PMID 9740979.

De Brito, S.A., Forth, A.E., Baskin-Sommers, A.R. et al. Psychopathy. Nat Rev Dis Primers 7, 49 (2021).

Frick PJ, Ray JV, Thornton LC, Kahn RE. Can callous-unemotional traits enhance the understanding, diagnosis, and treatment of serious conduct problems in children and adolescents? A comprehensive review. Psychol Bull. 2014 Jan;140(1):1-57. doi: 10.1037/a0033076. Epub 2013 Jun 24. PMID: 23796269.

Fox, B., & DeLisi, M. (2018). Psychopathic killers: A meta-analytic review of the psychopathy-homicide nexus. Aggression and Violent Behavior.

Hare, RD. (1996) Psychopathy and Antisocial Personality Disorder: A Case of Diagnostic Confusion Archived 2013-05-28 at the Wayback Machine Psychiatric Times

Meloy, J. Reid (1988). The Psychopathic Mind: Origins, Dynamics, and Treatment. Northvale, NJ: Jason Aronson Inc. p. 9. ISBN 978-0-87668-311-8.

Patrick, Christopher J. Handbook of Psychopathy Page 62

The Pocket Guide to the DSM-5 Diagnostic Exam Abraham M. Nussbaum, American Psychiatric Pub, 2013. Pg 236

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