Source: RossHelen/Shutterstock

The topic of psychopathy comes up frequently in the media, and one of the most common questions that psychologists on television and in print are asked sounds simple on the surface: “What’s the difference between a sociopath and a psychopath?” The answer, unfortunately, is complex, in part because the question is a bad question in the first place. The correct answer to the question requires reframing it entirely.

To begin with, “psychopath” is a term used to refer to someone who presents psychopathy, or psychopathic traits. “Sociopath,” “sociopathy,” and “sociopathic” are not true clinical terms, meaning they are not terms that are endorsed by either the American Psychiatric Association or another widely established, research-focused mental health professional, such as Robert Hare, the Canadian psychologist who created the measure used to diagnose psychopathy, the Psychopathy Checklist. To reiterate, “psychopath” is a clinical term, and “sociopath” is not a clinical term. (Mental health professionals should refrain from using any version of the term "sociopath." Since being trained in the Psychopathy Checklist, I, too, have learned to do the same.) 

The subject of psychopathy is further complicated by the existence of yet another term that is often used to describe a similar set of personality characteristics and behaviors: Antisocial Personality Disorder. In the media and in therapist offices across the world, the terms “psychopath” and “sociopath” are often used interchangeably, despite bearing real differences. The differences are illustrated here in the most concise form in the effort to help reduce confusion in the professional mental health community, the media, and among the public as well.

Antisocial Personality Disorder (ASPD) is a personality disorder which is included in the Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-V; American Psychiatric Association, 2013). ASPD focuses primarily on behaviors. DSM criteria include a disregard for and violation of others' rights since age 15, as indicated by seven possible features: failure to obey laws and norms by engaging in behavior which results in criminal arrest, or would warrant criminal arrest; lying, deception, and manipulation, for profit or self-amusement; impulsive behavior; irritability and aggression, manifested as frequently assaulting others, or engaging in fighting; blatant disregard of safety of self and others; a pattern of irresponsibility; and lack of remorse for actions.

The ASPD diagnostic structure, focusing on behaviors, was constructed with the attempt to make the diagnosis more reliable (and less subjective). The limitation, however, is that by focusing on behaviors, the construct doesn’t sufficiently account for the personality characteristics that are often seen in individuals who present this complex constellation of disordered behavior. In other words, the DSM’s construct of ASPD may be reliable, but it might not be as valid, because it omits a sufficient focus on the crucial psychopathic personality components.

Given the apparent deficiency in the DSM’s construct of ASPD, Canadian psychologist Robert Hare created the Psychopathy Checklist (Hare, 1980), a rating scale and inventory of perceived personality traits and observable behaviors used in the assessment of psychopathy in criminal populations. The original Psychopathy Checklist had 22 distinct items and included a semi-structured interview and review of collateral information, which may include official records.

The development of the Psychopathy Checklist reflects Hare and his colleagues’ belief that a more thorough diagnostic measure — including both behaviors and personality characteristics — was needed, because the construct of ASPD was not thorough enough to diagnostically capture men and women who present a disregard for rules, social conventions, and laws; are charming, manipulative, and exploitative; and don’t have empathy, guilt, or remorse. The Psychopathy Checklist was created with the intention of establishing a more objective measurement accessible to clinical and nonclinical investigators; to allow for consideration for lifetime personality and behavioral traits exhibited by the offender; and to connect the rating scale to the clinical construct of psychopathy as outlined by Hervey Cleckley, largely considered to be the pioneer of psychopathy (Brazil & Forth, 2016). Cleckley's core personality traits assessed in the Checklist include superficial charm; untruthfulness and insincerity; lack of nervousness; inadequately motivated antisocial behavior (they may do something harmful for no apparent reason); pathological egocentricity; lack of remorse and shame; and the inability to follow a life plan, among others (Cleckley, 1982). This list of core psychopathic personality traits underscores how psychopathy is different from Antisocial Personality Disorder, with a more in-depth assessment of personality than the Antisocial Personality Disorder diagnosis.

In 1991, Hare published the revised version of the checklist, the Psychopathy Checklist-Revised (Hare, 1991), and he published the second revision in 2003 (Hare, 2003). Note that the current version has 20 items, and that a score of 30 or higher on the scale designates someone as a "psychopath." In terms of how professionals should document a score of 30 or higher in a clinical report, I learned in my training for the Psychopathy Checklist-Revised that a clinical report should not include the label "psychopath" and should refer instead to the presentation of "psychopathic traits" or "severe psychopathic traits."

Put simply, what is the difference between ASPD and psychopathy?

The primary difference between Antisocial Personality Disorder and psychopathy is that ASPD focuses more on behavior, while psychopathy (diagnosed using the Psychopathy Checklist-Revised) includes a group of items (known as Factor 1 of the Checklist) which are commonly thought of as the core psychopathy personality traits (Skeem, Poythress, Edens, Lilienfeld, and Cale, 2002).

The fact that psychopathy is not included in the DSM-V (as Antisocial Personality Disorder is) does not mean that psychopathy is an inferior or inaccurate diagnostic construct. The Psychopathy Checklist and its revisions were developed using construct validity and statistical analysis, and The Psychopathy Checklist-Revised is used today in the court system, by the Federal Bureau of Investigations, and in other institutions.

To reduce misinformation and the public's confusion around the terms used to describe antisocial and psychopathic personality, my wish is that the American Psychiatric Association, which publishes the DSM, and Robert Hare and his prodigies could reach a meaningful consensus and settle on one diagnostic structure that best captures the complex behaviors and personality characteristics that are seen in these rare (1 percent?) individuals. What's more, shouldn't the psychopathic personality be included somehow in the profession's "bible" of diagnoses, the DSM? It may be that the construct requires one term with two variations. Other disorders are conceptualized in this way, including, for example, Bipolar I Disorder and Bipolar II Disorder. Perhaps what is needed is a construct in the DSM that includes Psychopathic I Personality Disorder or Psychopathic II Personality Disorder; perhaps what is needed is to include both Antisocial Personality Disorder and Psychopathic Personality Disorder in the DSM.

Until there is a reconciliation of these similar but different terms — antisocial and psychopathic — they will continue to be inaccurately used as synonyms, and the nonclinical term “sociopath” will continue to be used. Until a change takes place, mental health professionals should refer to either "antisocial personality" (the term endorsed by the APA) or "psychopathic traits" (the term endorsed by Hare and used in the assessment of psychopathy by many major law enforcement institutions).


American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Author.

Brazil K.J., Forth A.E. (2016) Hare Psychopathy Checklist. In: Zeigler-Hill V., Shackelford T. (eds) Encyclopedia of Personality and Individual Differences. Springer, Cham.

Cleckley, Hervey (1982). The mask of sanity. Revised Edition. Mosby Medical Library.

Hare, R. D. (1980). A research scale for the assessment of psychopathy in criminal populations. Personality and Individual Differences, 1,111–119.

Hare, R. D. (1991). The Hare Psychopathy Checklist—Revised. Toronto: Multi-Health Systems.

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

Skeem, Jennifer L.; Poythress, Norman; Edens, John F.; Lilienfeld, Scott O.; Cale, Ellison M. (2002). "Psychopathic personality or personalities? Exploring potential variants of psychopathy and their implications for risk assessment" (PDF). Aggression and Violent Behavior. 8 (5): 513–546. doi:10.1016/S1359-1789(02)00098-8.

Find a Therapist

Get the help you need from a therapist near you–a FREE service from Psychology Today.