Many forensic psychologists and criminologists use the terms sociopathy and psychopathy interchangeably. Leading experts disagree on whether there are meaningful differences between the two conditions. I contend that there are significant distinctions between them.

The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), released by the American Psychiatric Association in 2013, lists both sociopathy and psychopathy under the heading of Antisocial Personality Disorders (ASPD). These disorders share many common behavioral traits which lead to the confusion between them. Key traits that sociopaths and psychopaths share include:

A disregard for laws and social mores

A disregard for the rights of others

A failure to feel remorse or guilt

A tendency to display violent behavior

In addition to their commonalities, sociopaths and psychopaths also have their own unique behavioral characteristics as well.

Sociopaths tend to be nervous and easily agitated. They are volatile and prone to emotional outbursts, including fits of rage. They are likely to be uneducated and live on the fringes of society, unable to hold down a steady job or stay in one place for very long. It is difficult but not impossible for sociopaths to form attachments with others. Many sociopaths are able to form an attachment to a particular individual or group, although they have no regard for society in general or its rules. In the eyes of others, sociopaths will appear to be very disturbed. Any crimes committed by a sociopath, including murder, will tend to be haphazard and spontaneous rather than planned.

Psychopaths, on the other hand, are unable to form emotional attachments or feel real empathy with others, although they often have disarming or even charming personalities. Psychopaths are very manipulative and can easily gain people’s trust. They learn to mimic emotions, despite their inability to actually feel them, and will appear normal to unsuspecting people. Psychopaths are often well educated and hold steady jobs. Some are so good at manipulation and mimicry that they have families and other long-term relationships without those around them ever suspecting their true nature. When committing crimes, psychopaths carefully plan out every detail in advance and often have contingency plans in place. Unlike their sociopathic counterparts, psychopathic criminals are cool, calm, and meticulous.

The cause of psychopathy is different than the cause of sociopathy. It is believed that psychopathy is the result of “nature” (genetics) while sociopathy is the result of “nurture” (environment). Psychopathy is related to a physiological defect that results in the underdevelopment of the part of the brain responsible for impulse control and emotions. Sociopathy, on the other hand, is more likely the product of childhood trauma and physical/emotional abuse. Because sociopathy appears to be learned rather than innate, sociopaths are capable of empathy in certain limited circumstances but not in others, and with a few individuals but not others.

Psychopathy is the most dangerous of all antisocial personality disorders because of the way psychopaths dissociate emotionally from their actions, regardless of how terrible they may be. Many prolific and notorious serial killers, including the late Ted Bundy and John Wayne Gacy, and Dennis Rader ("Bind, Torture, Kill") are unremorseful psychopaths.

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