Psychopathy is a term derived from the Greek psukhe (mind) and pathos (disease, suffering), and was once used to refer to any mental disorder. Psychopathy is a psychological construct that describes chronic immoral and antisocial behavior. In the present time, psychopathy is best understood in the terms of two seminal works on the subject: Without Conscience by Robert Hare and The Mask of Sanity by Hervey M. Cleckley. A psychopath is said to be exactly that: conscienceless, and, most importantly, this is hidden from view behind a mask of normality that is often so convincing that even experts reportedly are deceived. A third, more recent work, Snakes In Suits by Robert Hare and Paul Babiak, has taken the research to a new level emphasizing the fact that, as a result of their ability to conceal their true nature, psychopaths easily become the Snakes in Suits that control our world. Harvard psychologist Martha Stout describes this lethal combination:
Imagine - if you can - not having a conscience, none at all, no feelings of guilt or remorse no matter what you do, no limiting sense of concern for the well-being of strangers, friends, or even family members. Imagine no struggles with shame, not a single one in your whole life, no matter what kind of selfish, lazy, harmful, or immoral action you had taken. And pretend that the concept of responsibility is unknown to you, except as a burden others seem to accept without question, like gullible fools. Now add to this strange fantasy the ability to conceal from other people that your psychological makeup is radically different from theirs. Since everyone simply assumes that conscience is universal among human beings, hiding the fact that you are conscience-free is nearly effortless. 
Psychopathy is defined in psychiatry as a condition characterised by lack of empathy or conscience, grandiosity, arrogance, callousness, superficiality, poor impulse control and manipulative behaviors designed to gain control of others and resources. The psychopath is also said to be short-tempered, lacking guilt and anxiety and is prone to delinquency and criminality.
Though in widespread use as a psychiatric term, psychopathy has no precise equivalent in either the DSM-IV-TR, where it is most strongly correlated with antisocial personality disorder, or the ICD-10, where it is correlated with dissocial personality disorder. This problem will be discussed under "History."
In current, clinical practice, psychopathy is most commonly diagnosed using Robert D. Hare's Psychopathy Checklist-Revised (PCL-R). Hare describes psychopaths as, "intraspecies predators who use charm, manipulation, intimidation, and violence to control others and to satisfy their own selfish needs. Lacking in conscience and in feelings for others, they cold-bloodedly take what they want and do as they please, violating social norms and expectations without the slightest sense of guilt or regret." Hare also suggests that despite the statistically small number of psychopaths in any given society, they are responsible for an extraordinary level of social distress.  Considering the research that shows psychopaths to be adept at achieving high positions in the corporate and political world, it could be said that the problem of psychopathy is the most important issue of modern society.
To the layperson, the term psychopathy can take on broader meanings, often being confused with psychosis, particularly by the use of the abbreviation psycho. People commonly take "psychopath" to be interchangeable with their personal perception of an evil person which is generally modeled on mad-dog serial killers as depicted in movies and literature. This is an unfortunate misperception.
What is a Psychopath?
"Likeable," "Charming," "Intelligent," "Alert," "Impressive," "Confidence-inspiring," and "A great success with the ladies": These are the sorts of descriptions repeatedly used by Hervey Cleckley in his famous case-studies of psychopaths, The Mask of Sanity. They are also, of course, "irresponsible," "self-destructive," and the like, though these characteristics can be well-hidden behind the mask. These seemingly contradictory descriptions highlight the great frustrations and puzzles that surround the study of psychopathy.
Researchers often point out that, on the surface, psychopaths seem to have in abundance the very traits most desired by normal persons. The untroubled self-confidence of the psychopath seems almost like an impossible dream and is generally what "normal" people seek to acquire when they attend assertiveness training classes. In many instances, the magnetic attraction of the psychopath for members of the opposite sex seems almost supernatural.
Psychopaths lack insight and any sense of responsibility or consequence. Their emotions are thought to be superficial and shallow, if they exist at all. They are considered callous, manipulative and incapable of forming lasting relationships or feeling any kind of love. It is thought that any emotions which the true psychopath exhibits are reproduced by watching and mimicking other people's emotions.
The average intelligence of psychopaths, if measured via commonly used tests, is somewhat lower than that of non-psychopaths, although their mental abilities are variegated. Psychopaths, contrary to popular myth, do not exhibit very high intelligence and there is a singular lack of technical or craftsmanship talents and skills among them as a group. 
Biologically speaking, the phenomenon is similar to color-blindness, except that, unlike color-blindness, it affects both sexes. Its intensity also varies ... from a level barely perceptive to an experienced observer to an obvious pathological deficiency. Like color-blindness, this anomaly also appears to represent a deficit in stimulus transformation, albeit occurring not on the sensory but on the instinctive level. The psychological picture shows clear deficits among men only; among women it is generally toned down, as by the effect of a second normal allele. This suggests that the anomaly is inherited via the X chromosome, but through a semi-dominating gene. This has not been confirmed by excluding inheritance from father to son.</p> Analysis of the different experiential manner demonstrated by these individuals caused us to conclude that their instinctive substratum is also defective, containing certain gaps and lacking the natural syntonic responses commonly evidenced by members of the species Homo Sapiens. 
In spite of their deficiencies in experiencing and understanding human emotion, and suffering from certain intellectual limitations, it has been observed that psychopaths do have a special genius, a sort of knowledge of their own, that seems to be due to the fact that they can observe and assess - without emotion - other human beings in all kinds of situations and relationships, and plan their own actions without reference to emotional bonds or considerations. Psychopaths carefully observe non-psychopaths, making assessments, deriving conclusions, becoming experts in human emotional weaknesses and often undertake heartless experiments for their own amusement. The suffering they cause others never makes them feel guilty because, in their view, the suffering is a result of weaknesses in non-psychopathic humans whom they consider to be not quite conspecific. Just as normal people are made happy by making others happy, the psychopath seems to derive a sort of happiness - or satisfaction - by causing others to suffer.
Psychopaths learn to recognize each other in a crowd as early as childhood, and they develop an awareness of the existence of other individuals similar to themselves. They are also conscious of being different from the majority of non-psychopaths. It has been observed that they view non-psychopaths - normal humans - as something akin to another species, and this view is most often that of a predator stalking prey. Normal people with their ordinary world-view cannot perceive or properly evaluate the existence of this world of predatory psychopathic concepts.
Researchers have been able to gain some knowledge about the inner world of psychopaths only because of the failures of some of them, those who commit crimes and end up in prisons or psychiatric hospitals where they can be studied. In this way, the researchers have been able to "learn their language" and gain some idea of their concepts of the world, though it must be noted that psychopaths only submit to being studied if they believe there is some advantage to themselves. It has been observed by researchers that the psychopath is incapable of incorporating the concepts and world-view of the non-psychopath even when they try. Any apparent results have repeatedly been shown to be a role they play (often, quite well) and a mask behind which they hide their deviant reality.
In any society in this world, psychopathic individuals often create an active network of common collusions, partially estranged from the community of normal people. They are aware of being different. Their world is forever divided into “us and them”; their world with its own laws and customs and that other "foreign world" of normal people that they consider to be full of presumptuous ideas and customs about truth and honor and decency in light of which they know they are condemned morally. Their own twisted sense of honor compels them to cheat and revile non-psychopaths and their values. In contradiction to the ideals of normal people, psychopaths feel non-fulfillment of their promises is customary behavior. Not only do they covet possessions and power, but they gain special pleasure in usurping and taking from others (a symbolic sibling, for example); what they can plagiarize, swindle, and extort are fruits far sweeter than those they can earn through honest labor. They also learn how their personalities can have traumatizing effects on the personalities of non-psychopaths, and how to take advantage of this root of terror for purposes of achieving their goals.
As mentioned, most studies of the psychopath have taken place among prison populations, though it has often been suggested that the psychopath is just as likely to sit on a Board of Directors as behind bars, concealing his true nature behind his well crafted "Mask of Sanity". Cleckley gives grounds for the view that psychopathy is quite common in the community at large. He has collected some cases of psychopaths who generally function normally in the community as businessmen, doctors, and even psychiatrists.
Being without emotion means that they are essentially very efficient machines, like a computer; they are able to execute very complex routines designed to elicit from others support for what they want. In this way, many psychopaths are able to reach very high positions in life. It is only over time and due to careful observation that their associates become aware of the fact that their climb up the ladder of success is predicated on violating the rights of others, most often covertly, behind layers of lies. "Even when they are indifferent to the rights of their associates, they are often able to inspire feelings of trust and confidence."
It has been shown that punishment and behavior modification techniques do not improve the behavior of a psychopath. They have been regularly observed to respond to such efforts both by becoming more cunning and hiding their behavior better. This will be discussed more thoroughly under "Response to Treatment."
Psychopaths also have a markedly distorted sense of the potential consequences of their actions, not only for others, but also for themselves. They do not, for example, deeply recognize the risk of being caught, disbelieved or injured as a result of their behaviour. This may relate to an inability to conceptualize abstractions such as past or future.
In Cleckley's speculations on what was "really wrong" with these people, he comes very close to suggesting that they are human in every respect - but that they lack a soul. This lack of "soul quality" makes them very efficient "machines." They can speak eloquently, write scholarly works, imitate the words of emotion, and temporarily act them out, but over time, it becomes clear that their words do not match their actions or what is actually inside them.
Mimicry is often used to convince others that the psychopath is a normal human being and has normal emotions. He does this to create a false empathy with his victim. The psychopath will work to make his victim and observers believe he has normal emotions by spinning sad tales or professing to have had profound, moving experiences.  The pity factor is one reason why victims often fall for these "poor" people. Lying is like breathing to the psychopath. When caught in a lie and challenged, they make up new lies, and don't care if they're found out. As Hare states,
Lying, deceiving, and manipulation are natural talents for psychopaths... When caught in a lie or challenged with the truth, they are seldom perplexed or embarrassed -- they simply change their stories or attempt to rework the facts so that they appear to be consistent with the lie. The results are a series of contradictory statements and a thoroughly confused listener. 
Often, their behavior is designed to confuse and repress their victims, or to negatively influence anyone who might listen to the victim's side of the story. Manipulation is the key to their conquests, and lying is one way they achieve this.
Adolf Guggenbuhl-Craig states that "they are very talented at appearing much more humble than the average person, but are hardly so." Psychopaths seeking political office or sympathy are able to feign concern about the lower classes and profess that they are on the side of the underdog, the poor, and so forth.
Some psychopaths can even be very fond of animals (contrary to the common viewpoint), but still view them as objects in relation to themselves.
Interest in the psychopathic personality pattern goes back to Aristotle . In 1801, Philippe Pinel described patients who were mentally unimpaired but nonetheless engaged in impulsive and self-defeating acts. He saw them as la folie raisonnante ("insane without delirium") meaning that they fully understood the irrationality of their behavior but continued with it anyway. Pinel was one of the last to study psychopathic personalities without including a moral judgment in his diagnosis. By the turn of the century Maudsley had begun writing about the moral imbecile, and was arguing that such individuals could not be rehabilitated by the correctional system.
Maudsley included the psychopath's immunity to the reformational effects of punishment, owing to their refusal anticipate further failure, and punishment. In 1904, Emil Kraepelin described four types of personalities similar to the antisocial personality disorder. By 1915 he had identified them as defective in either affect or volition, dividing the types further into categories only some of which correspond to the current descriptions of antisocial.
In the 19th and early 20th century, the term was applied to conditions in which disturbances in emotion or actions occurred in the absence of any intellectual defect. These conditions were often referred to as manie sans delire, moral insanity, monomania, and folie lucide.  These types of cases sharply defined the fact that mental disorder could exist in a mind where reasoning was intact.
One condition that was identified during this early period of the development of modern psychiatry was called Impulsion (impulsive insanity). This was explained as a disturbance in actions that was "unreflective" (without due consideration for consequences) or "involuntary aggression" and the absence of any other symptoms of mental disturbance. According to Berrios , this provided the "kernel around which the notion of psychopathic personality was eventually to become organised." 
There was an important forensic reason for the development of the concept in this way: in order for legal testimony of clinicians to be relevant in criminal courts, there needed to be a classification that was something other, or beyond, the classification of "total insanity." It was clearly understood that there were criminals who were not functionally insane, yet who committed vile and heinous crimes because something was clearly "wrong" with them.
A change came in the first half of the 20th century: the concept of psychopathy was narrowed to refer to personality disorder in a general sense. Personality disorder was then defined as a "chronic disturbance of emotion or volition, or a disturbance of their integration with intellectual functions, that resulted in socially disruptive behavior."  This was an important shift from thinking of psychopaths as "damaged" individuals to understanding that they were "damaging."  However, at this point in time, there was little agreement among clinicians as to how to differentiate the various personality disorders or to name them. There was, nevertheless, a consensus that one important cluster of disorders was characterized by impulsive, aggressive and antisocial behavior.
According to Eastern European clinical psychologist, Andrzej Łobaczewski, the clinicians in Europe at the time maintained that there were several types of psychopathy including asthenic, schizoidal, anankastic, hysterical. He also suggests that the practice of psychiatry and psychology are professions that are particularly attractive to psychopaths, an idea that is supported by Hervey Cleckley, Robert Hare and Paul Babiak, and that this is the primary reason for the historical diagnostic confusion and degradation of the study of psychopathy itself.
Łobaczewski discusses the fact that in Nazi Germany and Stalinist Russia, the psychological sciences were co-opted to support totalitarian regimes and that this was done by psychopaths in power who then set about destroying any possibility of accurate information about the condition being widely propagated. He points out that any regime that is composed primarily of pathological deviants cannot allow the science of psychology to develop and flourish freely because the result would be that the regime itself would be diagnosed as pathological thus revealing "the man behind the curtain." Awareness of the diagnosis would reinforce psychological resistance on the part of normal human beings who are the majority of any society, and would furnish them with new measures of self defense. He asks: "Can any pathological empire risk permitting such a possibility?" Any possibility of such a situation developing must thus be staved off prophylactically and skillfully, both within and without the empire.
Based on first hand observations of the phenomenon in question, Łobaczewski states that the repression of knowledge is undertaken in the typical manner of the psychopath: covertly and behind a "Mask of Sanity." In order to be able to control the psychological sciences, one must know or be able to sense what is going on and which fragments of psychopathology are most dangerous. A pathological political regime locates those individuals in the field who are psychopaths, (usually very mediocre scientists), facilitates their academic studies and degrees and the obtaining of key positions with supervisory capacity over scientific and cultural organizations. They are then in position to knock down more talented persons, governed both by self-interest and that typical jealousy which characterizes a psychopath's attitude toward normal people. They are the ones monitoring scientific papers for their “proper ideology” and attempting to ensure that a good specialist will be denied the scientific literature he needs. Łobaczewski writes about the problem as follows:
Scientific papers published under such governments or imported from abroad are monitored, research funds are denied to those who undertake research in certain directions. Specialists with superior talent can become the objects of blackmail and malicious, covert control. This of course causes the science of psychology to become inferior with reference to psychopathology. The entire operation must of course be managed in such a way as to avoid attracting the attention of public opinion. Often, scientists doing investigative work in this area are destroyed without a sound and suspicious persons are forced abroad to become the objects of organized harassment campaigns there. Written and unwritten lists are compiled for subjects that may not be taught, and corresponding directives are issued to appropriately distort related subjects. The list is so vast in the area of psychology that little remains of this science except a skeleton picked bare of anything that might be subtle or penetrating. A psychiatrist’s required curriculum contains neither the minimal knowledge from the areas of general, developmental, and clinical psychology, nor the basic skills in psychotherapy. Thanks to such a state of affairs, the most mediocre of physicians can become a psychiatrist after the barest minimum of course work. This opens the door of psychiatric careers to individuals who are by nature inclined to serving a pathological regime, and it has fateful repercussions upon the level of knowledge. It later permits psychiatry to be abused for purposes for which it should never be used.[...]
The essence of psychopathy may of course not be researched or elucidated. Appropriate darkness is cast upon this matter by means of an intentionally devised definition of psychopathy which includes various kinds of character disorders, together with those caused by completely different and known causes. One might admire how the above mentioned definition of psychopathy effectively blocks the ability to comprehend phenomena covered therein. ...
The “ideological” battle is thus waged on a territory completely unperceived by most people, including scientists and researchers in the field in question. In the meantime, however, the necessary scientific data and papers must be obtained somehow, taking difficulties and other people’s lack of understanding into account. Students and beginning specialists not yet aware of what was removed from the educational curricula attempt to gain access to the scientific data stolen from them. Science starts to be degraded at a worrisome rate once such awareness is missing. We need to understand the nature of the macrosocial phenomenon as well as that basic relationship and controversy between the pathological system and those areas of science which describe psychological and psychopathological phenomena. Otherwise, we cannot become fully conscious of the reasons for such actions. [...]
A normal person’s actions and reactions, his ideas and moral criteria, all too often strike abnormal individuals as abnormal. For if a [psychopath] considers himself normal, which is of course significantly easier if he possesses authority, then he would consider a normal person different and therefore abnormal... That explains why a [pathological] government shall always have the tendency to treat any dissidents as “mentally abnormal”. Operations such as driving a normal person into psychological illness and the use of psychiatric institutions for this purpose take place in many countries where [psychopaths achieve political power]. Contemporary legislation ... is not based upon an adequate understanding of the psychology of such behavior, and thus does not constitute a sufficient preventive measure against it. [...]
A normal person strikes a psychopath as a naive, smart-alecky believer in barely comprehensible theories; calling him “crazy” is not all that far away. Therefore, when we set up a sufficient number of examples of this kind or collect sufficient experience in this area, another more essential motivational level for such behavior becomes apparent. What happens as a rule is that the idea of driving someone into mental illness issues from minds with various aberrations and psychological defects.
...Well–thought out legislation should therefore require testing of individuals whose suggestions that someone else is psychologically abnormal are too insistent or too doubtfully founded. On the other hand, any system in which the abuse of psychiatry for allegedly political reasons has become a common phenomenon should be examined in the light of similar psychological criteria extrapolated onto the macro-social scale. Any person rebelling internally against a governmental system, which strikes him as foreign and immoral, and who is unable to hide this well enough, can easily be designated by the representatives of said government as “mentally abnormal”, someone who has a "personality disorder" and should submit to psychiatric treatment. A scientifically and morally degenerate psychiatrist becomes a tool easily used for this purpose. This becomes a method of terror and human torture... The abuse of psychiatry ... thus derives from the very nature of a government with psychopaths in power. After all, that very area of knowledge and treatment must first be degraded to prevent it from jeopardizing the system itself by pronouncing a diagnosis, and must then be used as an expedient tool in the hands of the authorities. ...
The psychopaths in power feel increasingly threatened whenever the medical and psychological sciences make significant progress. After all, not only can these sciences knock the weapon of psychological conquest right out of their hands; they can even strike at the very nature of such a government, and from inside the empire, at that. A specific perception of these matters therefore bids the psychopaths in power to be “ideationally alert” regarding psychology. This also explains why anyone who is both too knowledgeable in this area and too far outside the immediate reach of such authorities must be accused of anything that can be trumped up, including psychological abnormality. 
In 1941, Hervey Cleckley authored his magnum opus The Mask of Sanity: An Attempt to Clarify Some Issues About the So-Called Psychopathic Personality. This became a landmark in psychiatric studies and was repeatedly reprinted in subsequent editions though it is now out of print and the copyright holder states that there are no plans to print it again. Dr. Cleckley revised and expanded the work with each edition published in his lifetime. The second American edition of 1950 underwent the most substantial additions and improvements. Robert Hare's "Psychopathy Checklist" is based in part on Dr. Cleckley's work. The The Mask of Sanity is distinguished by its central thesis, that the psychopath exhibits normal function according to standard psychiatric criterion, yet privately engages in destructive behavior. The book was intended to assist with detection and diagnosis of the elusive psychopath for purposes of palliation and not as a cure for the condition itself.
The idea of a master deceiver secretly possessed of no moral or ethical restraints, yet behaving in public with excellent function, electrified American society and led to heightened interest in both psychological self-introspection and the detection of hidden psychopaths in society at large, leading to a refinement of the word itself into what was perceived to be a less stigmatizing term, "sociopath."
Over the past 50 years, the concept of psychopathy has been narrowed sharply and now refers to a specific personality disorder though there have been attempts to do away with the classification entirely, switching to "Antisocial Personality Disorder" which can embrace a wide variety of publicly visible behaviors without necessarily requiring the clinical diagnosis of psychopathy. Robert Hare insists that it is important to understand that psychopathy is not synonymous with criminality or violence; not all psychopaths engage in violence and criminal behavior. At the same time, not all violent persons or criminals are psychopaths. He writes:
Although psychopaths clearly are prone to violate many of society's rules and expectations, some manage to avoid formal contacts with the criminal justice system. Some are unreliable and untrustworthy employees; unscrupulous, predatory businessmen; corrupt politicians; or unethical and immoral professionals whose prestige and power are used to victimize their clients, patients, and the general public. Except for occasional news and anecdotal clinical reports, we know little about these individuals. Systematic research is needed to determine the prevalence of psychopathy in the general population, the varieties of criminal and noncriminal ways in which the disorder manifests itself, and the extent to which research with criminal psychopaths informs us about psychopaths in general. With respect to the latter issues, there are indications that the personality structure and propensity for unethical behavior probably are much the same in criminal and noncriminal psychopaths 
What is a Psychopath?: Diagnostic Controversy
It is important when considering this question to understand that there is a controversy. On the one side, there is the traditional description of psychopathy derived from the above mentioned European tradition discussed by Lobaczewski, combined with the older North American Tradition of Hervey Cleckley, Robert Hare and others. This is in general agreement with the experiences of practicing psychiatrists, psychologists, criminal justice personnel, experimental psychopathologists, and even members of the lay public who have had personal encounters with psychopathy.
On the other side of the issue, is what is called a "neo-Kraepelinian" (Emil Kraepelin) movement in psychodiagnosis which is closely associated with research coming out of Washington University in St. Louis, Missouri. This latter view is most closely aligned with the diagnostic criteria of the DSM-III, DSM-III-R, and DSM-IV for Antisocial Personality Disorder. The fundamental approach of this school is that assessment of a psychopath rests almost entirely on publicly observable or known behaviors. The assumption is that a clinician is incapable of reliably assessing interpersonal or affective characteristics (the internal landscape). Another assumption is that early onset delinquency is a cardinal symptom of ASPD. This tends to put heavy emphasis on delinquent and antisocial behavior, i.e., publicly observable behaviors that may have no bearing on the internal make-up of the individual.
The criteria of the DSM-III for ASPD was decided by a committee of the American Psychiatric Association's DSM-III Task Force and was revised only slightly by another committee for the DSM-III-R. The DSM-IV criteria were also decided by committee, with little regard for empirical research. . These criteria are less behaviorally focused and thus, somewhat resemble the criteria for other DSM-IV personality disorders.
According to Robert Hare et al, Cleckley, Łobaczewski, and many other experts in psychopathy, a diagnosis of psychopathy cannot be made on the basis of visible behavioral symptoms to the exclusion of interpersonal and affective symptoms because such a procedure essentially makes psychopaths of many people who are simply injured by life or society and allows the true psychopaths who have a well-constructed "mask of sanity" to escape detection.
Based on a growing body of literature, many (or most) psychopaths grow up in stable, well-to-do families, and become white collar criminals who, because of money and position, never have their private destructive behaviors exposed to public view and repeatedly avoid contact with the justice system. 
The widely publicized work of Robert Hare and Paul Babiak in their book Snakes in Suits demonstrates that psychopathy should be assessed using expert observer ratings based on a clinical interview, compared against a review of case history materials including any criminal or psychiatric records, interviews with family, friends, co-workers, employers and employees, supplemented with behavioral observations whenever possible.
The DSM-IV criteria do not constitute a scale or test.
The assessor determines if each criterion is present/true or absent/false. The final decision is: if the criteria are all present, then a lifetime diagnosis of ASPD is made; if one or more is absent, no such diagnosis is made. It can be observed that many psychopaths would easily evade detection via this system and many individuals who are possibly suffering from abuse or terrorization would be classified as ASPD.
Because of the problems with the DSM-III and DSM-III-R diagnosis of ASPD, the American Psychiatric Association carried out a muti-site trial to gather data in preparation for DSM-IV.  The field trial was designed to determine if personality traits could be included in the criteria for ASPD (which relies only on publicly evident behavior), without reducing reliability. The intention of those clinicians who lobbied for this was to bring ASPD back into line with clinical tradition and to end the confusion between ASPD and Psychopathy. The results of the field trials demonstrated that most of the personality traits that reflect the symptoms of psychopathy were as reliable as the behavior specific DSM-III-R items, thus invalidating the original premise for excluding personality from the diagnosis of ASPD/psychopathy.  In other words, including the PCL-R Factor 1 items in the criteria would have improved the validity of ASPD without sacrificing reliability. IRT analyses  show that Hare's PCL-R actually measures the latent trait of psychopathy across its entire range! Similar analyses of the field trial data show that the ASPD criteria was less discriminating of the psychopathy trait, particularly at high levels of the trait! In other words, the ASPD criteria set up by the DSM-III-R was designed - intentionally or not - to exclude the most psychopathic psychopaths!
Despite the fact that, after this study, there was an empirical basis for increasing the content-related criteria of ASPD in DSM-IV, this did not happen. It was argued by the DSM-IV committee that the average clinician would not use the carefully structured approach to the assessment of personality traits used in the field trial. Surprisingly, the criteria adopted for DSM-IV were not even evaluated in the field trial. What was evaluated was the 10-item set of adult symptoms (Criterion C) for ASPD listed in DSM-III-R. The seven-item set now listed in DSM-IV was derived from the 10-item set. More than that, the field trial did not include evaluations of Criterion B (conduct disorder before age 15), a criterion listed in DSM-IV as a necessary condition for a diagnosis of ASPD!
The DSM-IV text description of ASPD (which it says is "also known as psychopathy") contains references to traditional features of psychopathy but is incongruent with the formal diagnostic criteria in many ways. The "Associated Features" section of the text contains a statement parahrased by Robert Hare: "Lack of empathy, inflated and arrogant self-appraisal, and glib, superficial charm are features of ASPD that may be particularly useful in prison or forensic settings wherein criminal, delinquent and aggressive acts will be less specific to the disorder".  The problem that this presents is that the words used to describe these and related affective and interpersonal features are those typically associated with psychopathy and were based heavily on the 10-item psychopathic personality disorder set derived from the PCL-R. One is compelled to conclude that DSM-IV contains two sets of diagnostic criteria for ASPD, one consisting of antisocial and criminal behaviors, and the other consisting of these behaviors plus clinical inferences about personality. What is worse, the clinician is not given any guidelines on how to make these inferences.
One of the consequences of the ambiguity inherent in DSM-IV ASPD/ psychopathy criteria is that it leaves the door open for court cases wherein one clinician can say that the defendant meets the DSM-IV definition of ASPD, and another clinician can say he does not, and both can be right! The first clinician can use the formal diagnostic criteria exclusively while the second clinician can say "yes, the defendant may meet the formal criteria, but he or she does not have the personality traits described in the "Associated Features" section of the DSM-IV text". In other words, a good psychopath with a good lawyer can commit any crime and get away with it. This failure of the DSM-IV to differentiate between psychopathy and ASPD can (and undoubtedly will) have very serious consequences for society. Robert Hare writes:
... most jurisdictions consider psychopathy to be an aggravating rather than a mitigating factor in determining criminal responsibility. In some states an offender convicted of first-degree murder and diagnosed as a psychopath is likely to receive the death penalty on the grounds that psychopaths are cold-blooded, remorseless, untreatable and almost certain to reoffend. But many of the killers on death row were, and continue to be, mistakenly referred to as psychopaths on the basis of DSM-III, DSM-III-R or DSM-IV criteria for ASPD (Meloy). We don't know how many of these inhabitants of death row actually exhibit the personality structure of the psychopath, or how many merely meet the criteria for ASPD, a disorder that applies to the majority of criminals and that has only tenuous implications for treatability and the likelihood of violent reoffending. If a diagnosis of psychopathy has consequences for the death penalty - or for any other severe disposition, such as an indeterminate sentence or a civil commitment - clinicians making the diagnosis should make certain they do not confuse ASPD with psychopathy. [...] Diagnostic confusion about the two disorders has the potential for harming psychiatric patients and society as well. Camouflage Society In my book, Without Conscience, I argued that we live in a "camouflage society," a society in which some psychopathic traits - egocentricity, lack of concern for others, superficiality, style over substance, being "cool," manipulativeness, and so forth - increasingly are tolerated and even valued. ... it is easy to see how both psychopaths and those with ASPD could blend in readily with groups holding antisocial or criminal values. It is more difficult to envisage how those with ASPD could hide out among more prosocial segments of society. Yet psychopaths have little difficulty infiltrating the domains of business, politics, law enforcement, government, academia and other social structures (Babiak). It is the egocentric, cold-blooded and remorseless psychopaths who blend into all aspects of society and have such devastating impacts on people around them who send chills down the spines of law enforcement officers.
Psychopathy's relationship with other mental health disorders
The issue of comorbidity is a topic of dispute between the above-mentioned schools of thought and the problems of the DSM-IV already discussed. It appears that the comorbidity of psychopathy with other psychiatric disorders is limited and confused.  Many of the traits that are commonly used to define psychopathy - impulsivity, egocentricity, callousness, irresponsibility, etc - also manifest in other disorders in varying combinations. In this respect, psychopathy is similar to the personality disorders defined in the DSM-IV. As mentioned above in the history section, according to Eastern European psychologist, Andrzej Łobaczewski, the clinicians of the old European school maintained that there were several types of psychopathy including asthenic, schizoidal, anankastic, hysterical.
Psychopathy, as measured on the PCL-R, is negatively correlated with all DSM-IV Axis I disorders except substance-abuse disorders. PCL-R Factor 1 is correlated with narcissistic personality disorder and histrionic personality disorder. PCL-R Factor 1 is associated with extroversion and positive affect. Factor 1, the so-called core personality traits of psychopathy, may even be beneficial for the psychopath (in terms of nondeviant social functioning).
PCL-R Factor 2 is particularly strongly correlated to antisocial personality disorder and criminality. PCL-R Factor 2 is associated with reactive anger, anxiety, increased risk of suicide, criminality, and impulsive violence.
Prevalence of Psychopathy
Estimates of the prevalence of any disorder of course depend on how the disorder is defined, how it is assessed, who is doing the assessment and why. Obviously, if there are political reasons to conceal the prevalence of psychopathy (i.e., that there are psychopaths in positions of political power, to which they gravitate naturally and have the skills to achieve), then the definition and assessment will be designed to utilize the category for political reasons.
In a recent paper,  the authors state:
Psychopathy, as originally conceived by Cleckley (1941), is not limited to engagement in illegal activities, but rather encompasses such personality characteristics as manipulativeness, insincerity, egocentricity, and lack of guilt - characteristics clearly present in criminals but also in spouses, parents, bosses, attorneys, politicians, and CEOs, to name but a few. (Bursten, 1973; Stewart, 1991). Our own examination of the prevalence of psychopathy within a university population suggested that perhaps 5% or more of this sample might be deemed psychopathic, although the vast majority of those will be male (more than 1/10 males versus approximately 1/100 females).
As such, psychopathy may be characterized ... as involving a tendency towards both dominance and coldness. Wiggins (1995) in summarizing numerous previous findings... indicates that such individuals are prone to anger and irritation and are willing to exploit others. They are arrogant, manipulative, cynical, exhibitionistic, sensation -seeking, Machiavellian, vindictive, and out for their own gain. With respect to their patterns of social exchange (Foa & Foa, 1974), they attribute love and status to themselves, seeing themselves as highly worthy and important, but prescribe neither love nor status to others, seeing them as unworthy and insignificant. This characterization is clearly consistent with the essence of psychopathy as commonly described.
The present investigation sought to answer some basic questions regarding the construct of psychopathy in non forensic settings... In so doing we have returned to Cleckley's (1941) original emphasis on psychopathy as a personality style not only among criminals, but also among successful individuals within the community.
What is clear from our findings is that (a) psychopathy measures have converged on a prototype of psychopathy that involves a combination of dominant and cold interpersonal characteristics; (b) psychopathy does occur in the community and at what might be a higher than expected rate; and (c) psychopathy appears to have little overlap with personality disorders aside from Antisocial Personality Disorder. ...
Clearly, where much more work is needed is in understanding what factors differentiate the law abiding (although perhaps not moral-abiding) psychopath from the law-breaking psychopath; such research surely needs to make greater use of non forensic samples than has been customary in the past.
Psychopathy in Children
"If you're antisocial but you come from a good home, the reasons for your violent behavior may have more to do with biology than your upbringing," says University of Southern California psychophysiologist Adrian Raine, Ph.D.
In 1979, sixteen-year-old Brenda Spencer received a rifle for her birthday. She used it to shoot children at an elementary school near her home (San Diego). Nine were wounded, two died. A reporter asked her later why she had done it and she answered "I don't like Mondays. This livens up the day."
In 1986, nine-year-old Jeffrey Bailey, Jr. pushed a three-year-old friend into the deep part of a motel pool in Florida because he wanted to see someone drown. As the child sank to the bottom of the pool, Jeffrey pulled up a deck chair to watch. When it was over, he went just got up and went home. When he was questioned, he was more interested in the fact that he was the center of attention than feeling remorse for what he had done.
On April 13, 2000, three first-graders in north-western Indiana were interrupted in the act of plotting to kill a classmate. They had formed a "hate" club and were trying to recruit other girls to join them in the planned slaughter. They were not yet sure whether they would shoot their target victim, stab her with a butcher knife or hang her.
These cases, and many more besides, make it increasingly clear that psychopathy is not exclusively an adult problem. Some child development experts believe that childhood psychopathy is increasing at an alarming rate. In the research, these children are regarded as "fledgling psychopaths" who will become increasingly more dangerous as they get older. As the research shows, most of them will not become killers but they certainly will learn better how to manipulate, deceive and exploit others for their own gain.
Some researchers believe that such children have failed to develop affectional bonds that allow them to empathize with another's pain and have, instead, developed traits of arrogance, dishonesty, narcissism, shamelessness, and callousness.
As noted above, over many years, the criteria for a diagnosis of psychopathy in adults has gone through a number of confusing conceptual changes. Psychopaths have been called sociopaths but they've also been distinguished as a separate and distinct group from sociopaths. The other complicating factor discussed above is the development of the diagnosis of Antisocial Personality Disorder, which overlaps with many traits of a psychopath but also has key differences. Therefore, it is not a surprise that juvenile psychopathy, too, has been poorly defined and confused with various youthful conduct disorders or that children have been diagnosed with conduct disorders who really should be diagnosed as psychopaths.
In the movie, The Bad Seed (1956), based on the novel 1954) by the same name, the psychopathic child, Rhoda, was depicted as cute, adorable, manipulatively affectonate, and deadly. The author of the book, William March was influenced by the work of Hervey Cleckley. Wikipedia erroneously states that the term "psychopath" was not in use at the time the book was written.
In Without Conscience Robert Hare quotes from The Bad Seed:
Good people are rarely suspicious: they cannot imagine others doing the things they themselves are incapable of doing; usually they accept the undramatic solution as the correct one, and let matters rest there. Then too, the normal are inclined to visualize the [psychopath] as one who's as monstrous in appearance as he is in mind, which is about as far from the truth as one could well get . . . These monsters of real life usually looked and behaved in a more normal manner than their actually normal brothers and sisters; they presented a more convincing picture of virtue than virtue presented of itself - just as the wax rosebud or the plastic peach seemed more perfect to the eye, more what the mind thought a rosebud or a peach should be, than the imperfect original from which it had been modeled.
Nature or Nurture?
Are psychopaths born or made?
...a child comes into the world with a certain genotype that is phenotypically expressed according to the vagaries of personal experience. 
The Instinctive Substratum or Psychobiological Foundation
Andrzej Lobaczewski discusses the role played by what he calls the instinctive substratum. He writes:
Man’s instinctive substratum has a slightly different biological structure than that of animals. Energetically speaking, it has become less dynamic and become more plastic, thereby giving up its job as the main dictator of behavior. It has become more receptive to the controls of reasoning, without, however, losing much of the rich specific contents of the human kind. ... This substratum contains millions of years’ worth of bio-psychological development that was the product of the species’ life conditions, so it neither is nor can be a perfect creation. Our well known weaknesses of human nature and errors in the natural perception and comprehension of reality have thus been conditioned on that phylogenetic level for millennia.[...]
Man has lived in groups throughout his prehistory, so our species’ instinctual substratum was shaped in this tie, thus conditioning our emotions as regards the mining of existence. The need for an appropriate internal structure of commonality, and a striving to achieve a worthy role within that structure, are encoded at this very level. [...]
Our zeal to control anyone harmful to ourselves or our group is so primal in its near-reflex necessity as to leave no doubt that it is also encoded at the instinctual level. [...]
It is also at this level that differences begin to occur between normal individuals, influencing the formation of their characters, world views, and attitudes. The primary differences are in the bio-psychical dynamism of this substratum; differences of content are secondary. For some people the sthenic instinct supersedes psychology; for others, it easily relinquishes control to reason. It also appears that some people have a somewhat richer and more subtle instinctual endowment than others. Significant deficiencies in this heritage nevertheless occur in only a tiny percentage of the human population; and we perceive this to be qualitatively pathological. 
J. Reid Meloy writes, along the same lines:
"The house of psychopath" is built on a psychobiological foundation of no attachement, underarousal, and minimal anxiety. ...</p> <p>Attachment is a biologically rooted, species-specific behavioral system that maintains close proximity between child and caretaker. It was first conceptualized and investigated by John Bowlby, James Robertson, and Mary Ainsworth at the Tavistock Clinic in London (Robertson and Bowlby, 1952; Bowlby, 1953; Ainsworth and Bowlby, 1954). Attachment is deeply rooted in both birds and mammals but is generally absent in reptiles. 
References to a "reptilian nature" of psychopaths occurs elsewhere in Meloy's work:
The other clinical observation that supports the hypothesis of a reptilian state among certain primitive psychopathic characters is the absence of perceived emotion in their eyes. Althought this information is only intuitive and anecdotal, it is my experience in forensic treatment and custody settings to hear descriptions of certain patients' or inmates' eyes as cold, staring, harsh, empty, vacant, and absent of feeling. Reactions from staff to this percetion of the psychopath's eyes have included, "I was frightened... he's very eerie; I felt as if he was staring right through me; when he looked at me the hair stood up on my neck."
This last comment is particularly telling since it captures the primitive, autonomic, and fearful response to a predator.
I have rarely heard such comments as these from the same experienced inpatient staff during highly arousing, threatening, and violent outbursts by other anger, combative patients. It is as if they sense the absence of a capacity for emotional relatedness and empathy in the psychopathic individual, despite his lack of actual physical violence at the moment. ...
I have found little in the research literature, either theoretical or empirical, that attempts to understand this act of visual predation in the psychopathic process. ... The fixated stare of the psychopath is a prelude to instinctual gratification rather than empathic caring. The interaction is socially defined by parameters of power rather than attachment. 
The curious references to a perception of the psychopath as being reptilian in essence is also suggested by Andrzej Lobaczewski, who writes about the effect of the psychopath on the normal human:
When the human mind comes into contact with this new reality so different from any experiences encountered by a person raised in a society dominated by normal people, it releases psychophysiological shock symptoms in the human brain with a higher tonus of cortex inhibition and a stifling of feelings, which then sometimes gush forth uncontrollably. Human minds work more slowly and less keenly, since the associative mechanisms have become inefficient. Especially when a person has direct contact with psychopathic [individual] who use their specific experience so as to traumatize the minds of the "others" with their own personalities, his mind succumbs to a state of short-term catatonia. Their humiliating and arrogant techniques, brutal paramoralizations, deaden his thought processes and his self-defense capabilities, and their divergent experiential method anchors in his mind. ...
Only after these unbelievably unpleasant psychological states have passed, thanks to rest in benevolent company, is it possible to reflect - always a difficult and painful process - or to become aware that one's mind and common senses have been fooled by something which cannot fit into the normal human imagination. 
The Reptilian Brain
According to theories of evolution, about a half billion years ago, many different types of vertebrates proliferated wildly over the earth's land surface. This was followed by a large variety of insects, amphibians and eventually the first dinosaurs. Over time, the brain also evolved in response to the effects of the continually changing environment. The limbic system and "reptilian brain" of more primitive life forms have not been replaced, but merely expanded upon.
The brain develops as a series of four separate brains, each with its own memory, motor and other functions. Each brain elaborates on the preceding level and adds increasing degrees of organization and self-preservation capacity to the vegetative functions of the hindbrain, midbrain, and spinal cord. The first "brain" described by Maclean is this "reptilian brain." This part of the brain is responsible for primitive levels of genetically transmitted knowing that result in repetitive and ritualistic migratory, territoriality, aggression and courtship behaviors. Maclean describes an important achievement of the reptilian brain as "homing", or the tendency to return to a recognized frame of reference after reaching out for a mate or food, etc. Mahoney relates this to the development of human "reality," which is our creation of an orderly and temporally stable world.
The second "brain" to develop is the limbic system, or "paleomammalian brain". This level integrates and refines life-relevant behavior patterns (feeding, aggression, and reproduction) and is best known for its role in emotional intensity and motivational complexity (Mahoney, 1991). The limbic system coordinates homeostatic life support, purposive action, memory, learning, and emotionality. As such, it involves its own primitive form of reflective intelligence and self-regulatory control.
The third, or "neomammalian" brain, also known as the "neocortex", accounts for 85% of the entire adult human brain. The frontal area, which is associated with higher level mental organization, intentionality, and self- awareness, is over six times as large as that of non-human primates of similar size (Mahoney, 1991). Mahoney cautions against thinking that, because it develops later, the rational intellectual functions of the neocortex enable it to override or control the passions of the limbic brain. Although under inhibitory control of the neocortex, parts of the limbic system with their primitive survival functions, can override neocortical control.(Joseph, 1992; Joseph, 1993; Mahoney, 1991).
The fourth human brain is seen in differentiation of the neocortex into two separate and independently functioning "higher brains" or cerebral hemispheres. In his original description of "the triune brain," MacLean denied the need to describe this fourth level of independent brain functioning, however the majority of modern neuroscientists have disagreed (Mahoney, 1991). Differentiation of these four brain systems and concomitant changes in emotion and thought occur primarily during early childhood, but continue into adolescence and even adulthood. When most of us see another persons distress, our emotional center, the limbic system, is aroused. We feel a little of what others are feeling. Hare and his colleagues (using functional magnetic resonance imaging (fMRI)) studied the neurological manifestations of the way psychopaths process different types of words. When non-psychopaths processed negative emotional words (e.g., rape, death, cancer), activity in the limbic regions of the brain increased. For psychopaths there was little or no increased activity in these regions.
In the Journal of Biological Psychiatry, Adrian Raine at the University of California explains that the brains of murderers, on average, have significantly lower rates of glucose uptake than the healthy brain of the control subjects. Raine, noted "Poor functioning of these limbic area helps explain why violent offenders fail to learn from experience and are less able to regulate their emotions.” 
Failure of Nurture - Bonding?
Many researchers are biased toward - and cling to - a "nurturing failure" explanation for psychopathy. Regarding this, Meloy notes:
...[T]he importance of biology in ... psychopathy should not be dismissed (Raine, 1993; Cooke, Forth, and Hare, 1998)... Studies have shown that psychopathy has a negative curvilinear relationship to neglectful and abusive childhood family experiences (Marshall and Cooke, 1999). In other words, those persons who are severely psychopathic were less influenced by family factors when they were growing up; whereas those with low-to-moderate psychopathy were strongly influenced by family experience. Neuroimaging (PET) also suggests that functional deficits measured by radioactive glucose among samples of murderers with extensive criminal histories are more pronounced among those from good rather than poor home environments (Raine, Stoddard, et al., 1998) 
Meloy describes the psychopath as follows:
The psychopath is an imposter. Shorn of any deep and abiding identifications with others, much of his subsequent behavior as an adult involves the conscious imitation and simulation of other people's thoughts, affects, and activities. ... I am using the term imitation to describe the intentional, conscious, mimicking of another person's attitudes or behavior. ...
Unlike the person with narcissistic personality disorder who consciously feels, at times, a sense of being a fake, the psychopathic character has no awareness of this "false self" or the "as if" quality of his phenomenal experience. He does not merely play the role, observing the limits of his character, but lives the part.
The psychopathic process may also be expressed by individuals whose simulations are so adept, whether they be cognitive, affective, or behavioral, that there is absolutely no suspicion whatsoever that pseudo-identifications may be occurring. This is especially difficult to assess in the socially engaging and intelligent psychopath. ... Any successful assessment of the nature and genuineness of identifications in these individuals must be largely dependent upon corroborative information from relatives, family, acquaintances, and other clinicians. 
DSM-IV APD and Children
Antisocial Personality Disorder is described in DSM-IV as ‘a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood… This pattern has also been referred to as psychopathy, sociopathy, or dyssocial personality disorder’.  This confusion of terminology, discussed above, is especially damaging for research because while DSM-IV describes APD as ‘associated with low socio-economic status’  psychopathy ‘seems less likely to be associated with social disadvantage or adversity’. 
Psychopathy is not associated with low birth weight, obstetric complications, poor parenting, poverty, early psychological trauma or adverse experiences, and indeed Robert Hare remarks ‘I can find no convincing evidence that psychopathy is the direct result of early social or environmental factors’. 
Cloninger’s Two-threshold Model for Inherited Psychopathy
Cloninger’s ‘two-threshold’ model suggests a polygenic and sex-limited contribution to psychopathy according to which more men than women would pass the threshold for activation of predisposing genes. This model predicts that males should be more susceptible to environmental influences and females who do become psychopathic should have a greater genetic predisposition; this is confirmed by the finding that the offspring of female psychopaths are more vulnerable than those of male psychopaths. 
One feature of psychopathy is that extremely violent and antisocial behaviour appears at a very early age, often including casual and thoughtless lying, petty theft, a pattern of killing animals, early experimentation with sex, and stealing.  In a study of 653 serious offenders, childhood problem behaviors provided convergent evidence for the existence of psychopathy as a discrete class, but ‘adult criminal history variables were continuously distributed and were insufficient in themselves to detect the taxon’.  In another study psychopathic male offenders were found to score lower than nonpsychopathic offenders on obstetrical problems and fluctuating asymmetry. The offenders meeting the most stringent criteria for psychopathy had the lowest asymmetry scores amongst offenders. 
Professor Adrian Raine directed a study in which scientists from USC and the University of California at Irvine used positron emission tomography (PET) to scan the brains of 38 men and women charged with murder. Some of the subjects had pleaded not guilty by reason of insanity, while the rest had been found incompetent to stand trial.
PET scans measure the uptake of blood sugar (glucose) in various brain areas during the performance of simple, repetitive tasks. (Glucose is the basic fuel that powers most cell functions. The amount used is related to the amount of cell activity.)
The researchers waded through piles of court records, attorney interviews, medical and psychological records, and newspaper articles searching for evidence about the subjects' upbringing; whether or not they had experienced physical or sexual abuse, neglect, extreme poverty, foster home placement, severe family conflict, a broken home, having a criminal parent -- all environmental risks commonly associated in people's minds with a propensity for violence.
The researchers rated the severity of the risks they found on a five-point scale, with 0 representing no abuse, 1 minimal, 2 partial, 3 substantial and 4 extreme.
Of the 38 murderers, only 12 were found to have suffered significant psychosocial abuse and deprivation (ratings 2 to 4). The remaining 26 were found to have experienced minimal abuse and deprivation or none (ratings 0 - 1).
Compared to the subjects from the assessed bad early environments, the 26 subjects from benign backgrounds averaged 5.7% less activity in the medial prefrontal cortex. More significantly, one particular part of the medial prefrontal cortex -- the orbifrontal cortex on the right hemisphere -- showed 14.2% less activity.
"Parents of violent kids think, 'What did I do wrong?'" says Raine, a professor of psychology in USC's College of Letters, Arts and Sciences. "When the kids come from a good home, the answer may be absolutely nothing. A biological deficit may be to blame."
Diagnosing Psychopathy in Children
Psychopathy is not normally diagnosed in children or adolescents, and some jurisdictions explicitly forbid diagnosing psychopathy and similar personality disorders in minors. Psychopathic tendencies can sometimes be recognized in childhood or early adolescence and, if recognised, are diagnosed as conduct disorder. It must be stressed that not all children diagnosed with conduct disorder grow up to be psychopaths, or even disordered at all, but these childhood signs are found in significantly higher proportions in psychopaths than in the general population.
Children showing strong psychopathic precursors often appear immune to punishment; nothing seems to modify their undesirable behavior. Consequently parents usually give up, and the behavior worsens.
Indicators of Psychopathy in Childhood
For some time, under the influence of the DSM-III, it was said that indicators of psychopathy in childhood included the following:
The three indicators, bedwetting, cruelty to animals and firestarting, known as the MacDonald triad, were first described by J.M. MacDonald as indicators of psychopathy. The relevance of enuresis to the etiology of psychopathy has since been called into question by MacDonald himself.  The latest information suggests that urinary incontinence is more likely to be a problem associated with social expectations and developmental delays. Historically, enuretic children have been subjected to distressing and painful methods of treatment, i. e., medications, mechanical devices, and pharmacologic preparations, to the point of permanent disability which certainly might cause conduct reactions. The modern emphasis on the problem of enuresis is focused on successful use of behavioral therapies and meaningful parent and child reeducation. Nevertheless, having been suggested (and accepted) as a sign of childhood psychopathy, this unfortunate label is difficult to remove.
The question of whether young children with these alleged early indicators of psychopathy respond poorly to intervention compared to conduct disordered children without these traits has only recently been examined in controlled clinical research. The findings from this research are consistent with broader evidence - pointing to poor treatment outcomes. 
Another study suggests that psychopaths have a genotype that results in an "inborn temperament or personality, coupled with a particular pattern of autonomic hypoarousal that, together, design the child to be selectively unresponsive to the cues necessary for normal socialization and moral development" 
Given the weakness of evidence for developmental instability and brain damage in psychopaths, attention should be paid to the probability that child psychopaths are mislabelled as suffering from Attention Deficit Hyperactivity Disorder, Conduct Disorder, or Oppositional Defiant Disorder. According to Hare ‘none of these diagnostic categories quite hits the mark with young psychopaths. Conduct disorder comes closest, but it fails to capture the emotional, cognitive, and interpersonal personality traits… that are so important in the diagnosis of psychopathy’ 
Implications for the Law and Society
It is important to note that psychopathy also has various, quite separate legal and judicial definitions that should not be confused with the medical definition. Various states and nations have at various times enacted laws specific to dealing with psychopathic offenders, and many of these laws are active, on statute, today:
- Washington State Legislature defines a "Psychopathic personality" to mean "the existence in any person of such hereditary, congenital or acquired condition affecting the emotional or volitional rather than the intellectual field and manifested by anomalies of such character as to render satisfactory social adjustment of such person difficult or impossible".
- In 1939, California enacted a psychopathic offender law  that defined a psychopath solely in terms of offenders with a predisposition "to the commission of sexual offenses against children." A 1941 law  attempted to further clarify this to the point where anyone examined and found to be psychopathic was to be committed to a state hospital and anyone else was to be sentenced by the courts.
- "Psychopathic Disorder" is legally defined in the The Mental Health Act (uk)  as, "a persistent disorder or disability of mind (whether or not including significant impairment of intelligence) which results in abnormally aggressive or seriously irresponsible conduct on the part of the person concerned".
In the past few years, the legal system has changed dramatically in regard to diagnoses of psychopathy among criminals. Whereas before, a clinical diagnosis of psychopathy was of little value in predicting criminal behavior, after the adoption of Robert Hare's PCL-R, the association between psychopathy and crime acquired empirical validity. There is now extensive evidence that, despite their statistically small number in the general population, psychopaths make up a significant proportion of prison populations and are responsible for a shocking amount of crime and social distress across the board.
The features that define the psychopath - they are emotionally unconnected to the rest of humanity and they view others as little more than objects - make it quite easy for them to victimize the vulnerable and to use whatever means they choose to obtain what they want in the way of material goods and power.
Nevertheless, criminal behavior is far more common in society than psychopathy. Non-psychopaths routinely engage in less serious criminal conduct or isolated instances of serious criminal acts. But the criminal careers of psychopaths are qualitatively different.  The psychopaths criminal behavior is even different from non-psychopaths whose criminal conduct is extremely serious and persistent. More than this, the studies show that the antisocial behavior of psychopaths is motivated by different factors than those things that motivate non-psychopathic criminals. The psychopath's M.O., the types of victims they choose, their behavioral profile in committing crimes is also different.
Psychopaths begin their criminal careers at a very young age and continue to engage in such activity throughout their lives  though studies show a marked reduction in criminality around the age of 35-40 with respect to non-violent crimes. . But, this does not mean that they have given up crime, it just means that their apparent criminal activity has decreased to the level of the average, non-psychopathic, persistent offender. It may also mean that they learn how not to get caught. The psychopathic tendency to violent crime and aggressive behavior does not appear to decrease with age. 
The question must be asked: are age-related reductions in the criminality of psychopaths a reflection of the fact that there are changes in their core personality traits?
The answer seems to be no. A PCL-R study of a large sample of male offenders ranging in age from 16 to 70 was conducted by Harpur & Hare in 1994. The scores on Factor 2 (socially deviant features) decreased sharply with age, while scores on Factor 1 (affective/interpersonal features) remained stable. This indicates that apparent age-related changes in the psychopath's antisocial behavior are not paralleled by changes in their egocentric, manipulative and callous traits, the fundament of psychopathy.
Psychopaths have a higher rate of violent crimes such as armed robbery, robbery, assault, and they engage in violence and homosexual aggression at a higher rate in prisons. Of psychopaths and non-psychopaths violent offenders in prison populations, psychopaths commit about three times more violent crimes.
Psychopaths not only have higher rates of violent crime, they commit different types of violent crimes than non-psychopaths. Two thirds of the victims of psychopaths were male strangers while two thirds of the victims of non-psychopaths were female family members or acquaintances. Non-psychopaths commit acts of violence while in states of extreme emotional arousal, while psychopaths cold-bloodedly select their victims for revenge or retribution. That is to say that psychopathic violence is instrumental, a means to an end, predatory. 
The fact that psychopathy is a risk factor for high rates of recidivism is well established.
Psychopaths and Sexual Violence
Among sex offenders in a treatment facility, rapists, those who had assaulted adolescents, and those who had assaulted children, had a base rate of psychopathy (PCL-R) of 76.5, 24.0, and 14.8 percent respectively. Half of all serial rapists may be psychopaths 
Rapists are classified into four basic types: vindictive, opportunistic, sadistic and non-sadistic. The primary motivation of the sadistic and non-sadistic types is sexual; the primary motivation of the vindictive and opportunistic types is aggressive or hostile. Psychopaths are found at a high statistical level among opportunistic and sadistic rapists. 81% of psychopathic rapists and 56% of non-psychopathic rapists were classified as either opportunistic or vindictive. 
Psychopaths use more frequent and more severe violence in the commission of sex offenses. The studies suggest that psychopathy may be associated with sexual sadism. High PCL-R scores are positively correlated with sexual arousal by violence assessed by penile plethysmography. 
One study found that within six years of release from prison, more than 80% of psychopathic sex offenders had violently recidivated, but only 20% of the non-psychopaths had done so. Many, but not all, of these offenses were sexual in nature.  In another follow-up study of a large sample, researchers obtained similar results with the additional report: sexual recidivism was strongly predicted by a combination of a high PCL-R score and phallometric evidence of deviant sexual arousal, defined as any phallometric test that indicated a preference for deviant stimuli such as children, rape cues, or nonsexual violence cues. 
Response to Treatment
A recent Canadian study on group treatment for 238 sex offenders (rapists, incest offenders) from Warkworth penitentiary in Ontario. These prisoners included some well-documented psychopaths. All were taught to "empathize" with victims, and understand their "offence cycle" as part of treatment. After their release, it was found that those who had scored highest in terms of "good treatment behaviour" and who had the highest "empathy" scores were the more likely to reoffend on release into the community. [...]
Psychotherapy doesn't just require a good theory and an astute clinician. It also requires a patient. The word patient comes from Latin, and means "to suffer." A patient, by definition, is bothered by something. Yet most treatments of prisoners originate not from the prisoner's suffering, but are mandated by the justice system. Corrections Canada knows many psychopaths will be released into the community eventually, so it attempts to change them, even though any psychotherapy for adults that has to be mandated is suspect.
Clinicians are justifiably pessimistic about the treatability of psychopaths. Psychopaths do not experience distress and do not think that anything is wrong with them, they do no suffer stress or neuroses, and thus do not seek out treatment voluntarily. They do not consider their attitudes and behavior to be at all wrong, and do not benefit from the many treatment programs that have been set up to help them "develop empathy" and interpersonal skills. The psychopath recognizes no flaw in his psyche, no need for change.
Freud argued psychopaths are untreatable in psychotherapy precisely because having a conscience is a prerequisite for being able to use psychotherapy. It is the conscience, and the related capacity for concern for others, that drives the serious scrutiny of one's motives, which underlie one's behaviour. Yet psychopaths lack conscience and concern by definition.
When the recidivism rate of psychopaths and other offenders who had been in treatment was examined, it was found that the rate of general recidivism was equally high in the treated and untreated group, 87% and 90% respectively, however the rate of violent recidivism was significantly higher in the treated group than the untreated group; 77% and 55% respectively. In contrast, the treated non-psychopaths had significantly lower rates of general and violent recidivism; 44% and 22% respectively, than did untreated psychopaths, 58% and 39%. So it seems that treatment programs work for non-psychopaths, but actually make true psychopaths worse. Another reason to be extremely careful about the diagnostic criteria. 
The question is: how can therapy make someone worse? Robert Hare's conjecture is that group therapy and insight-oriented therapy actually help psychopaths to develop better ways of manipulating, deceiving and using people but do nothing to help them understand themselves.
The problems with treating psychopathy may be partly due to the weaknesses of the relevant literature which underpins the assessment procedures advocated by the DSM-IV. Without an accurate assessment, it is difficult to formulate a well-defined treatment plan. Further, lack of adequate experimental groups and control groups make it difficult to be sure that "nothing works." Robert Hare has suggested that a program that is less concerned with trying to help the psychopath develop empathy and conscience (changing personality), and more concerned with convincing the psychopath that they alone are responsible for their behavior and that they can learn pro-social ways of using their inherent strengths and weaknesses to satisfy their needs and wants. The only seeming weakness in such an idea is that it would not satisfy one of the psychopath's most prominent tendency: the desire for power and control over others.
The Etiology of Psychopathy
Psychopathy as Adaptation: The Sociobiological Model
Despite the fact that psychopathy is viewed as a mental disorder, some sociobiologist view it as only one of several possible adaptive strategies for passing on genes to the next generations. One has to wonder if this favorable view is not held by psychopathic sociobiologists.
While most humans only have a few children and spend much of their productive life caring for them, psychopaths use an adaptive "cheating" strategy by which they are able to have large numbers of children and give little or no time to caring for them. Either strategy can be successful depending on the prevailing social, economic and environmental factors. "The mobile, nomadic lifestyle of psychopaths, and the ease with which they adapt to new social environments, can be seen as part of a constant need for fresh breeding grounds.  The "migration" hypothesis seems to have some support in a study of Scottish criminals. The prevalence of psychopathy was higher among those who emigrated to England than among those who remained in Scotland. 
Psychopathy as a Variant of Normal Personality
This model does not discuss psychopathy as a disorder but rather suggests that psychopathy is an extreme variation of certain basic traits of normal personality.
One researcher conceives of psychopathy as "a dimension of personality disorder linked in turn to the structure of personality as it is currently understood. I have suggested that psychopathy can be understood primarily as the coercive control of interpersonal transactions, and that social cognitive processes may be a possible key to understanding."  He also suggests that psychopathy, distasteful as it might be to the larger majority of normal people, represents one way of trying to make sense of the world as they see it.
Personality trait models assume behavioral genetics. One study indicated the heritability estimate for callousness, conduct problems, and narcissism is .56, .56, and .53, respectively. These heritability estimates are similar to those obtained for normal personality traits and antisocial behaviors. 
Psychopathy as Brain Dysfunction: The Neurological Model
One theory that has been around for a long time is that the psychopath's brain matures at a very slow rate. There is some evidence that some parts of the brain, including the frontal cortex and its associated neural pathways, continue to develop into early adulthood, and there are reports of similarities between the recorded brain waves of adult psychopaths and those of normal adolescents. There are also some similarities between some of the psychopaths' characteristics - egocentricity, impulsivity, selfishness, and unwillingness to delay gratification - and the typical characteristics of children. So, some researchers suggest that all this means that psychopathy is little more than delayed development.
There are arguments against this theory. The brain-wave characteristics in question are also associated with drowsiness or boredom in normal adults and could result form the psychopath's lack of interest in the routine procedures used to measure them.  Moreover, it is not likely that the egocentricity or impulsivity of a child and a psychopath are really comparable.
A related model posits that psychopathy is associated with brain damage or dysfunction, especially in areas responsible for planning and executive processes.  This model is based on some apparent behavioral similarities between psychopaths and patients with damage to the frontal lobes of the brain , but the similarities appear to be only superficial.
Several researchers argue that some sort of frontal-lobe dysfunction - not necessarily damage - may be involved.  Recent research supports this thesis.
Psychopathy as Early Adversity: The Attachment Model
The most common view is that psychopathy is due to early psychological trauma or adverse social experiences. It is certainly true that many people are psychologically damaged by a wide range of early experiences including parental rejection, neglect, deprivation, and abuse. One very popular view is that if these adverse experiences occur in the first two years of life, they can disrupt the normal processes of healthy psychological development, including the process of becoming "attached" to the primary caregiver. This "attachment failure" is then thought to play a role in the development of psychopathy.
The argument against this theory is that there is little empirical evidence to support these ideas and there is significant empirical evidence to contradict it. That leads to the argument that so-called attachment and socialization problems are more the result of the psychopathic traits born in a person than the cause.
Psychopathy as Adult Expression of Early Pathology
Investigators have identified a small subset of children whose personality, psychophysiology, and behaviors are similar in many ways to those of adult psychopaths. These children tend to exhibit the symptoms of both attentional deficit hyperactivity disorder (ADHD)and conduct disorder.  These researchers have suggested that the combination of these disorders is the important factor for diagnosing the "fledgling psychopath" and the model has better content validity than CD of ADHD alone.
A specially developed, age-appropriate version of the PCL-R has been utilized with children to identify a cluster of traits similar to those in PCL-R Factor 1) described as callous-unemotional (absence of empathy, absence of guilt). It was concluded that these traits develop out of a biologically based tendency toward lo behavioral inhibition.  The researcher suggested further that "dysfunctional parenting practices may play a major role in the development of conduct problems primarily in children without (callous-emotional) traits. (p. 179, emphasis in the original.) One can assume, then, that children with these traits develop conduct problems on their on.
The research of Forth & Burke  reveals that the quality of family background is less of a factor in the development of criminal behavior of psychopathic offenders than it is in other offenders.
Robert Hare suggests that psychopathy "emerges from a complex - and poorly understood - interplay between biological factors and social forces. Social forces and parenting practices may influence the way in which the disorder develops and is expressed in behavior, but they are not the sole or primary causes of the disorder.  This model is supported by mounting evidence that genetic factors determine the basic personality and brain function and this influences the way a person responds to and interacts with life and the environment.
Psychopathy as Learning Deficit I: Fearlessness
Forty years ago Lykken argued that psychopaths are relatively fearless and this makes it difficult for them to "learn to avoid antisocial behaviors and to inhibit forbidden impulses through punishment and the fear it leaves behind."  He proposed that this fearlessness might reflect an extreme variant of genetic normality rather than a psychosocial stress or structural brain damage. There are compelling arguments for the fearlessness model that explain a range of antisocial behaviors and laboratory findings.
The argument against this model is that it does not explain the full range of psychopathic symptomatology. Attempts to explain egocentricity, shallow emotions, lack of guilt and remorse, in terms of fearlessness are less convincing. The fact is, the fearlessness model is easily subsumed into the "weak behavioral inhibition model." 
Psychopathy as Learning Deficit II: Weak Inhibition
Gray has described a neuro-physiological behavioral inhibition system (BIS)that controls an organism's response to signals of impending punishment or frustration of non-reward. The behavioral activation system (BAS), controls responses to signals of impending reward. Arousal of the BIS is experienced as negative affect and leads to inhibition of motor activity that would lead to the expected punishment or non-reward. He posits that a weak BIS can result in the failure to inhibit activity that may lead to punishment or not getting what is wanted. 
The argument against this model is that it is like the "fearlessness model" in that it cannot account for the interpersonal and affective traits of the psychopath. Also, Gray's model provides "several pathways to disinhibition" including hyperresponsivity to reward due to a strong BAS and abnormal responsivity to punishment due to deficient BIS while linking impulsivity to a strong BAS.  Thus, it would be more appropriate to describe the behavior of psychopaths as disinhibited rather than impulsive. Also, though the BIS model receives some support from studies of electrodermal responsivity, fear conditioning, and passive avoidance studies , psychopaths may not be hyporesponsive to punishment per se, but rather only when they are faced with a competing choice of reward. 
Psychopathy as Learning Deficit III: Deficient Response Modulation
Newman and Wallace have developed a more elaborate version of the BIS model. They posit that "the 'impulsive' behavior of psychopaths appears to reflect difficulty in the automatic switching of attention which, in turn, interferes with their ability to assimilate unattended but potentially relevant information while they are engaged in the organization and implementation of goal-directed behavior."  That is to say, they are concentrating so hard on what they are doing they don't notice anything else around them. Hare suggests that, just as the fearlessness model can be subsumed to the weak BIS model, so can the BIS model be subsumed into this model.  This model also explains the finding that psychopaths exhibit hypo-responsivity to punishment only under specific circumstances. This model may also explain a noted psychopathic deficiency in the processing of language and emotional cues.
The argument against this model is that, despite the methodological sophistication of the model and the clever experiments, the results just aren't that strong or compelling. 
Psychopathy as Cognitive-Affective Dysfunction: Neurobiological
Robert Hare investigated the anxiety and anxiety mediated behaviors of psychopaths.  He and his colleagues found that the fearlessness model described above had a major flaw. It seems that the small skin conductance responses shown by psychopaths in anticipation of an unpleasant stimulus were accompanied by a large increase in heart rate. At the same time, a large skin conductance response exhibited by a non-psychopath was accompanied by a decrease in heart rate.  That is to say, a novel, in the non-psychopath, an interesting and/or important event elicits an increase in skin conductance and a decrease in heart rate, while unpleasant or threatening events elicit a defensive response which includes an increase in both akin conductance and heart rate. In other words, non-psychopaths focus attention on the impending unpleasant stimulus and experience an increase in fear, while psychopaths simply "tune out" the impending stimulus and experience little or no fear. That is, the increase in heart rate combined with the low skin conductance may indicate that the psychopath has a dynamic protective mechanism that attenuates the psychological/emotional cues of impending pain or punishment.
Hare has more recently proposed that psychopathy, rather than being a specific emotional deficit or dysfunction, is instead the result of general difficulties processing and understanding deep semantic and affective meaning. This view is supported by the fact that psychopathy is characterized by a wide range of cognitive and affective anomalies. 
In a study of reaction times to various words, emotional, neutral, pseudo words, it was noted that the Event-related brain potentials in lexical decision tasks among non-criminals indicate that responses to both positive and negative words are more accurate and faster than are those to neutral words. In the brains of these subjects, the central and parietal sties indicated early and late ERP components in respect of emotional words. The late components of the ERP were thought to indicate continued processing of the word. 
In this same study, non-psychopathic criminals also demonstrated sensitivity to the emotion laden words. The psychopaths, however, failed to show any reaction time or ERP differences between neutral and emotional words. More than that, the morphology of their ERPs was strikingly different from that of non-psychopaths. The late component of the ERP that was long and large in non-psychopaths was small and brief in psychopaths. It is thought that this reflects the fact that psychopaths make lexical decisions and process information in a shallow way. This is supported by recent brain-imaging studies which show that psychopathic substance abusers have less cerebral activity during performance of a lexical decision task than non-psychopathic substance abusers. 
Kiehl, Hare, McDonald and Brink have even more recently discovered that the ERP anomalies of psychopaths are not specific to affective language but also include abstract language.  Another curious finding noted in two separate studies was an unusually large negative wave that swept over the frontal areas of the brain. A tentative interpretation of this is that it is a reflection of a profound cognitive and affective processing anomaly. 
Other recent studies lead to similar results and conclusions: that psychopaths have great difficulty processing verbal and nonverbal affective material, that they tend to confuse the emotional significance of events, exhibit unusual inter-hemispheric distribution of processing resources, have difficulty in appreciating the subtle meanings and nuances of language such as proverbs, metaphors, and so forth, have poor olfactory discrimination, possibly because of orbito-frontal dysfunction, and may have what appears to be a sub-clinical from of thought disorder characterized by a lack of cohesion and coherence in speech.  All of these cognitive and affective anomalies cannot be explained by any of the other models of psychopathy described above. Hare writes:
Recent advances in the neurobiology of cognition and affect provide some potentially fruitful leads. Clearly, we must pay particular attention to the interrelated functions of ventromedial prefrontal cortex, anterior temporal cortex, anterior cingulate cortex, and amygdala. These regions have rich afferent and efferent connections with each other and with other regions important in the processing and integration of semantic and affective information, planning, impulsivity, and the initiation and inhibition of behavior. Behavioral and neuroimaging studies indicate that damage to these regions can produce a dissociation of the logical/cognitive and affective components of though not unlike that found in psychopaths. 
In the final analysis, we find that whether or not psychopathy is the result of brain dysfunction or disorganization, unusual cerebral asymmetry, or general difficulties in information processing, are complex and poorly understood. Recent advances in neuroscience have brought about powerful new tools for determining if psychopathy is the result of structural or functional anomalies, or disruptions in the normal transmission of information in the brain. Magnetic Resonance Imaging is very promising in these studies. More research and more funding is needed.
But, just as we nave noted the resistance of those individuals who control the arbiter of our psychological reality - the DSM-IV - are reluctant to admit a coherent and accurate diagnostic criteria of psychopathy, so are those same groups reluctant to fund the research on psychopathy that is so desperately needed.
While few psychopaths commit violent crimes, the callousness of the average psychopath usually ranges through subtle, but still devastating misdeeds:
Parasitically bleeding other people of their possessions, savings, and dignity; aggressively doing and taking what they want; shamefully neglecting the physical and emotional welfare of their families; engaging in an unending series of casual, impersonal, and trivial sexual relationships; and so forth." [Hare, 45].
Hervey Cleckley's List
Hervey Cleckley defined psychopathy thus:
- Superficial charm and average intelligence.
- Absence of delusions and other signs of irrational thinking.
- Absence of nervousness or neurotic manifestations.
- Untruthfulness and insincerity.
- Lack of remorse or shame.
- Antisocial behavior without apparent compunction.
- Poor judgement and failure to learn from experience.
- Pathological egocentricity and incapacity to love.
- General poverty in major affective reactions.
- Specific loss of insight.
- Unresponsiveness in general interpersonal relations.
- Fantastic and uninviting behavior with drink, and sometimes without.
- Suicide threats rarely carried out.
- Sex life impersonal, trivial, and poorly integrated.
- Failure to follow any life plan.
PCL-R: Psychopathy Checklist
In contemporary research and clinical practice, psychopathy is most commonly assessed with the Hare Psychopathy Checklist-Revised (PCL-R), which is a clinical rating scale with 20 items. Each of the items in the PCL-R is scored on a three-point (0, 1, 2) scale according to specific criteria through file information and a semi-structured interview. This assessment tool also includes, as mentioned above, case history materials including any criminal or psychiatric records, interviews with family, friends, co-workers, employers and employees, supplemented with behavioral observations whenever possible.
1. GLIB and SUPERFICIAL CHARM -- the tendency to be smooth, engaging, charming, slick, and verbally facile. Psychopathic charm is not in the least shy, self-conscious, or afraid to say anything. A psychopath never gets tongue-tied. They have freed themselves from the social conventions about taking turns in talking, for example.
2. GRANDIOSE OPINION OF SELF-WORTH -- a grossly inflated view of one's abilities and self-worth, self-assured, opinionated, cocky, a braggart. Psychopaths are arrogant people who believe they are superior human beings.
3. NEED FOR STIMULATION or PRONENESS TO BOREDOM -- an excessive need for novel, thrilling, and exciting stimulation; taking chances and doing things that are risky. Psychopaths often have a low self-discipline in carrying tasks through to completion because they get bored easily. They fail to work at the same job for any length of time, for example, or to finish tasks that they consider dull or routine.
4. PATHOLOGICAL LYING -- can be moderate or high; in moderate form, they will be shrewd, crafty, cunning, sly, and clever; in extreme form, they will be deceptive, deceitful, underhanded, unscrupulous, manipulative, and dishonest.
5. CONNING AND MANIPULATIVENESS- the use of deceit and deception to cheat, con, or defraud others for personal gain; distinguished from Item #4 in the degree to which exploitation and callous ruthlessness is present, as reflected in a lack of concern for the feelings and suffering of one's victims.
6. LACK OF REMORSE OR GUILT -- a lack of feelings or concern for the losses, pain, and suffering of victims; a tendency to be unconcerned, dispassionate, coldhearted, and unempathic. This item is usually demonstrated by a disdain for one's victims.
7. SHALLOW AFFECT -- emotional poverty or a limited range or depth of feelings; interpersonal coldness in spite of signs of open gregariousness.
8. CALLOUSNESS and LACK OF EMPATHY -- a lack of feelings toward people in general; cold, contemptuous, inconsiderate, and tactless.
9. PARASITIC LIFESTYLE -- an intentional, manipulative, selfish, and exploitative financial dependence on others as reflected in a lack of motivation, low self-discipline, and inability to begin or complete responsibilities.
10. POOR BEHAVIORAL CONTROLS -- expressions of irritability, annoyance, impatience, threats, aggression, and verbal abuse; inadequate control of anger and temper; acting hastily.
11. PROMISCUOUS SEXUAL BEHAVIOR -- a variety of brief, superficial relations, numerous affairs, and an indiscriminate selection of sexual partners; the maintenance of several relationships at the same time; a history of attempts to sexually coerce others into sexual activity or taking great pride at discussing sexual exploits or conquests.
12. EARLY BEHAVIOR PROBLEMS -- a variety of behaviors prior to age 13, including lying, theft, cheating, vandalism, bullying, sexual activity, fire-setting, glue-sniffing, alcohol use, and running away from home.
13. LACK OF REALISTIC, LONG-TERM GOALS -- an inability or persistent failure to develop and execute long-term plans and goals; a nomadic existence, aimless, lacking direction in life.
14. IMPULSIVITY -- the occurrence of behaviors that are unpremeditated and lack reflection or planning; inability to resist temptation, frustrations, and urges; a lack of deliberation without considering the consequences; foolhardy, rash, unpredictable, erratic, and reckless.
15. IRRESPONSIBILITY -- repeated failure to fulfill or honor obligations and commitments; such as not paying bills, defaulting on loans, performing sloppy work, being absent or late to work, failing to honor contractual agreements.
16. FAILURE TO ACCEPT RESPONSIBILITY FOR OWN ACTIONS -- a failure to accept responsibility for one's actions reflected in low conscientiousness, an absence of dutifulness, antagonistic manipulation, denial of responsibility, and an effort to manipulate others through this denial.
17. MANY SHORT-TERM MARITAL RELATIONSHIPS -- a lack of commitment to a long-term relationship reflected in inconsistent, undependable, and unreliable commitments in life, including marital.
18. JUVENILE DELINQUENCY -- behavior problems between the ages of 13-18; mostly behaviors that are crimes or clearly involve aspects of antagonism, exploitation, aggression, manipulation, or a callous, ruthless tough-mindedness.
19. REVOCATION OF CONDITION RELEASE -- a revocation of probation or other conditional release due to technical violations, such as carelessness, low deliberation, or failing to appear.
20. CRIMINAL VERSATILITY -- a diversity of types of criminal offenses, regardless if the person has been arrested or convicted for them; taking great pride at getting away with crimes.
- ↑ Bruce A. Arrigo. "The Confusion Over Psychopathy (I): Historical Considerations". International Journal of Offender Therapy and Comparative Criminology, Vol. 45, No. 3, 325-344 (2001). Retrieved on 2007-12-15.
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