Murder is the most serious of all crimes. Therefore, knowledge that can help to predict and thus potentially prevent extraordinary violence is worth reporting. The purpose of this paper is to document the psychological, neurological, and experiential factors that consistently appeared in the cases of nine adolescents who later committed murder and to compare these adolescents with a sample of 24 delinquents who did not go on to commit violent acts within 6 years of discharge from a juvenile correction facility. With the exception of a single paper describing one young murderer (1), to the best of our knowledge all of the literature on the neuropsychiatric antecedents of homicide is retrospective.
There is a controversy in the literature regarding the prevalence and severity of mental illness in murderers. McKnight et al. (2) found that 77% of 100 murderers received psychiatric diagnoses (schizophrenia, especially paranoid, manic-depression, psychopathic personality, and epilepsy). In fact, 55% were unfit to stand trial and 27% were found not guilty by reason of insanity. That study was, however, skewed by the fact that the sample was taken from a prison hospital. Several other authors (3-7) have found murderers to have a higher prevalence of psychoses, especially the schizophrenias, than the general population. Wolfgang (8), on the other hand, found that only 3% of the murderers in Philadelphia prisons were insane. Gillies (9) found 90% of his Scottish sample of murderers to be normal and free of psychiatric diagnoses. Once again, results vary (2, 10). Wong and Singer (11) found that only 7% of the 621 murderers they studied in Hong Kong were mentally ill or not guilty by reason of insanity.
The literature on homicidal aggression from the 1940s, 1950s, and early 1960s focused primarily on social and psychodynamic factors to the almost complete exclusion of neurobiologic factors (12-18). Sargent (13) described five murderous children and hypothesized a family conspiracy in which the child who killed acted out an unconscious parental wish. Easson and Steinhilber (12) presented eight cases of attempted homicide, none of which was successful. Their conclusion was similar to Sargent’s: “All cases demonstrate that one or both parents had fostered and had condoned murderous assault.” Michaels (19), using Easson and Steinhilber’s clinical data, highlighted factors that Easson and Steinhilber had minimized, namely, history of enuresis, epilepsy, and abuse. Martin (14) evaluated the psychodynamics of two adolescent murderers but failed to elaborate on several symptoms of organic brain impairment, which he mentioned only in passing. Smith (15), after evaluating eight young murderers, concluded that they suffered from early experiences of deprivation which resulted in underdeveloped egos and vulnerability to outbursts of violent aggression. Miller and Looney (18) theorized that adolescents who tended to dehumanize others were at greatest risk of committing murder when their wishes were thwarted. In 1978 McCarthy (20) discussed the psychodynamics of 10 adolescent murderers and found that “narcissistic disturbances, particularly an impaired capacity for self-esteem regulation and underlying narcissistic rage, were related to homicidal behavior.” Malmquist (21) suggested that homicide “can serve the illusory function of saving one’s self and ego from destruction by displacing onto someone else the focus of aggressive discharge.”
Much has been written about the association of parental brutality and homicidally aggressive behavior (3, 16-18, 22-24). King (17) noted that the nine adolescent murderers he studied were “often singled out for abuse.” The presence of repeated violence and abuse in the environment of many adolescent murderers led Pfeffer (25) to view much of the adolescent’s assaultive and homicidal behavior as an attempt to master the trauma he has experienced by controlling and victimizing others. Sendi and Blomgren (3) noted that an exposure to extreme violence or murder differentiated their group of 10 murderers from a control group. They also reported that seduction by or sexual perversion of a parent was associated with homicidal youth.
Duncan and Duncan (22) and Lander and Schulman (26), in studies based on small numbers of cases, described destructive and nonnurturing parent-child relationships and hypothesized that these may have led to acting out of intense hostility and homicidal behavior. McCarthy (20) asserted that early deprivation is often associated with homicidal behavior. Corder et al. (23, 24) reported severe psychopathology in parents of homicidal adolescents. They described “extreme maladjustment, e.g., chronic alcoholism, repeated hospitalization for psychosis, and many incarcerations for criminal acts.”
There is a continuing debate in the literature about whether psychomotor epilepsy and violence are associated with each other. Although some authors (27-34) have called attention to an association between the two, others (35-39) have questioned the relationship.
King (17) and others (40, 41) have reported extensive information pointing to the presence of a continuum of learning deficits and neurological problems associated with youthful homicide. Lower intelligence and mental retardation have also been reported to play a role in homicide (2, 6, 10, 42). King (17) and Lion (43) studied the effects of cognitive and language communication deficits in homicidal youths. Their studies showed that these adolescents may have an “inability” or “disinclination” to master language and basic communication skills.
The studies we have cited can be characterized in two ways. First, each study tends to focus on a single dimension of behavior (e.g., psychodynamic, neurological, experiential). Second, all of the studies of more than one subject are retrospective. That is, they reconstruct childhood factors after murder has occurred. For these reasons, we considered it important to report the neuropsychiatric and psychosocial characteristics of nine murderers examined before their commission of homicidal acts.