This article discusses the motives of serial killers from the perspective of behavior theory, implying that notwithstanding environmental, social and familial factors, the offender must ultimately act in terms of a negative feedback-correction paradigm. Diagnostic implications are discussed in that context
The motive of serial killers is a topic that has been discussed from various perspectives ever since 1888, when Jack the Ripper went on his rampage in London’s Whitechapel district. Unfortunately there is still no answer to the question of why certain people commit such deplorable acts. That is not surprising. Over time there have been a vast number and wide variety of violent felons but only a few have been characterized as serial killers. That makes the phenomenon so rare as to be an item of both disdain and fascination. As rational creatures only occasionally disposed to fits of anger, and with legal, social and cultural ways of resolving conflict it is extremely hard for clinicians, law enforcement personnel and lay persons to comprehend why a person would kill at random, and apparently out of sheer habit.
In many ways the actions of serial killers make no sense, either psychologically or biologically. They are not typically unattractive or unintelligent so one could assume that whatever sexual, social or personal needs they might have could be met through less violent means. Some, like Dennis Rader and John Wayne Gacy were married. Others like Ted Bundy did not lack in social graces or physical appeal. Furthermore, as Rader stated in one of his attention-seeking communiqués, killing another person requires energy summoned as rage, time, effort, planning, a summoning of the most primal urges and a bypass of conscience. Rage is not a comfortable state, which is why most creatures in nature resort to it only when it becomes necessary to remove imminent threats or ensure survival.
Periodic killing requires extreme psycho-emotional mobilization. It entails duress and an almost unfathomable summoning of psychological defenses as cushion against the act. Consequently, the idea of engaging routinely in such acts might seem implausible absent some dire need that could not be met in any other way.
Perhaps dire need is involved. Perhaps the only way to understand why a serial killer would be prompted to engage in such unconscionable acts is to assume each act is one of desperation. That would still not address the question of etiology but one can draw certain assumptions based on well established behavioral principles.
Despite all the mystery and symbolism typically associated with serial killers, the action of killing periodically comprises a behavior pattern. Therefore it must be possible to explain at least some of its origin and psychological components through traditional behavioral theory. That premise will serve as a focal point for subsequent discussion.
A CLINICAL/OPERANT ANALYSIS
Since we are all to an extent operant creatures (in that our behavior is guided by either positive (pleasurable) negative (pain avoidance) or congruent (self-concept affirming) feedback it would seem the killer’s acts must fall into one or more of those motivational categories. At present there is no concrete evidence to indicate which motive or motives are typically prominent, or for that matter, whether there is a true common thread running through each act and each offender.
This topic has been broached in clinical circles as well as in the media and on film, for example in books on Ted Bundy by Sullivan (2009), Larson (1980) and Kendall (1981), books on Jeffrey Dahmer by Davis (1991), on John Wayne Gacy by Cahill (1986) and on Dennis Rader, aka “BTK” by Bardsley, Beli et al (2008), These are in some instances excellent and informative accounts of the lives of these men – particularly the book by Kendall, who was Bundy’s fiancé for a time. Yet none of the books offers any answer to the question of motive.
One would think discussion with people close to the offenders might shed light on the matter. Yet family members and close associates generally have no clue as to why the serial killer got started on his spree. Making things even more confusing is that siblings born and raised in the same family as the offender have typically shown no such tendencies.
There have been references to behavior traits and episodes that typify serial killers. One of the first to discuss these features was Kraft-Hebbing, as referenced by Knight (2006). The former developed a list of factors central to the serial killer profile, which include:
● Absence of psychosis
● A psychopathic/narcissistic personality constellation
● A history of maternal overprotection, coupled with paternal detachment or abuse
● A history of early childhood trauma coupled with interest in pornography and paraphilias
● Lack of superego function
Wilson and Seamon (1995) offered further elaboration on the typical profile by adding;
● Coming from a broken home
● Lack of discipline
● Experience of sexual abuse (They indicated, however that only 50 % fit into this category).
Other have opined on the topic of causation. For example Castle proposed the “military theory” of serial murders, referencing the fact that some serial killers had military experience. Eysenck suggested the behavior was so outside the norm that biological factors would have to be involved – a notion dispelled by Holmes & Holmes (1998).
Unfortunately none of these concepts offers complete clarification. For one thing there is too much overlap with the normal population for any of these indicators to be seen as independent or even prime variables. Many children engage in cruel and/or aggressive acts toward animals. Such acts can include pulling a dog’s tail, tossing a cat across the room, swatting flies, or even hunting deer with father. Very few of the children who engage in such behavior become serial killers. Many children come from broken homes, suffer abuse, have sexual fetishes and even have sociopathic tendencies. Very few engage in serial killing.
Media portrayals aren’t much help. On film serial killers are often depicted as being highly intelligent, prone to ritual and with a need to flaunt their superiority by sending cryptic messages to police and other perceived authority figures. It is an unnecessarily mystical scenario which does not always play out in real life. For example Bundy sent no messages. Neither did Albert DeSalvo (the Boston Strangler), the Riverside Stranglers or The Green River killer. BTK (Dennis Rader) and the Zodiak killer did. So did Jack the Ripper, but this is not a common thread. Most serial killers do not have a need to torment the authorities. In fact their behavior is typically clandestine. Bodies are buried in remote places, most attacks occur at night and while some serial killers have no qualms about disclosing their “methodology” they generally work very hard to conceal their identity.
The ritual component, or modus operandi for the crime, is confusing, not so much due to the vagueness of the symbolism supposedly conjured up by the offender, but due to the fact that there are two mutually opposite ways to look at a ritual. One is by assuming there is some psychological reason for using the same instruments for each crime; for example handcuffs in Bundy’s case, rope and nylon stockings with the DeSalvo murders, knives with the Ripper. However it could also be that the weapons, times and places entailed in the crime are based mostly on practical considerations, more specifically expediency. As crass as it might sound, the offender might be solely concerned with carrying out his act in a way he deems most likely to succeed, using skills and knowledge of weapons with which he is most familiar.
Why didn’t the Ripper use a gun? Perhaps because he had no expertise with guns, or because guns make a loud noise and that would have raised the likelihood of his being caught in the act. Why did Bundy use variously knives, clubs and ropes? Why did Rader’s choice of weapons include knives, stockings, belts and plastic bags? It would seem that convenience rather than ritual was involved – something expressed by Bundy in an interview prior to his execution.
Thus while the ritual theory holds that the offender wants to disclose his identity and/or the “true meaning” of the crime, much of the evidence suggests the opposite. To some extent serial killers seem to operate like most criminals. They want to commit the act and avoid being caught.
Yet there is clearly more to it than that, particularly in differentiating between the traditional violent offender and the serial killer. In a sense that distinction provides a clue as to the motive of the latter. The difference is that the traditional killer’s actions are externally driven. That does not excuse what they do of course, but it does at least put their actions into a comprehensible context. Mafia hit men, angry, murderous spouses, thieves fearful of being identified – people who murder under such circumstances are all externally guided. A particular person does something to anger someone else, the someone else decides to retaliate against that particular person. It is personal, rather than impersonal and objectified. Not true of the serial killer. In his or her case motive does not come from an external source, nor from a specific event. It appears to come almost totally from within – as though taking the form of a psychic resolution. The most confounding aspect of this is that most serial killers are not psychotic. Therefore one must ask what that source of internal duress might be.
Therein lies a problem,. The acts of serial killers are so incongruous with regard to social norms that we often assume they function on an entirely different plane than the rest of us. In this opinion that mindset can lead to distracting emphases on the symbolism, motive and personality of the offender and ultimately take discussion beyond the parameters of behavior theory. The problem is that behavior theory is ostensibly applicable to all creatures in nature, at least in the sense that behavior (no matter how aberrant) can never operate beyond the parameters of a negative feedback-correction/adaptation paradigm.
Since few clinicians ever treat or evaluate serial killers the sample for research and/or diagnostic categorization are small. And when the offenders are interviewed they typically engage in self-serving rhetoric, ostensibly in an attempt to reinforce the mythology that has sadly been romanticized in our culture. In initial interviews Ted Bundy said he did not know why he killed all those young women. Later, prior to his execution, he claimed it was caused by his reading pornographic magazines. Jeffrey Dahmer seems to have been a bit more consistent – or at least less self-serving. Just prior to his death at the hands of a fellow inmate he said that after much deliberation he really could not come up with an explanation or motive behind his heinous acts.
Conventional wisdom has it that sexuality has much to do with the murders. At face value that makes sense. For most males, the first experience with sex is through masturbation. It is obviously a one-sided affair (pardon the pun). To the extent that a young male develops a sexual comfort zone in which the object of his desire is a figment of the imagination, or even a picture in a magazine, he can theoretically become over-acclimated to a totally passive partner, who looks good enough to foment desire but does not talk, move, contradict or pass judgment. In other words autoeroticism is tantamount to conflict-free (thus anxiety-free) sex. It is conceivable that some males in extreme circumstances, could learn to associate sexual gratification with complete female passivity. They could conceivably develop an association between low anxiety and sexual gratification. If so, then the complex interaction required to meet sexual needs in a real, personal way might increase social conflict, raise anxiety levels and create an approach-avoidance scenario in which sex would equate with fear of rejection, criticism and other possibilities. Such a mindset could create a potentially nonmalleable association between female personhood and dampened sexual arousal and vice versa. Given enough time and anger It would not be too unlikely for the killer to equate female non-personhood (or complete passivity) with death. In that case only the death of a female or victim could provide the kind of anxiety-free arousal required to provide sexual gratification.
On the other hand most males engage in masturbation yet come to enjoy sexual relations with real, walking, talking, thinking women. Once again the overlap between serial killers and normal males with overlapping experience creates a diagnostic conundrum.
A PSYCHO-BIOLOGICAL CONCEPT
Freud saw a direct relationship between sex and aggression. In Three Essays on Sexuality (1905) he suggested that if not for sexual attraction the conflict between men and women derived from personal needs, conflict and psychic incompatibility would produce more hate than love. Just because Freud said this doesn’t make it right, however. Some theoreticians maintain that in the course of evolution, monogamy in human society resulted from an empathic quality in both males and females whereby the former instinctively protected the latter and the latter attained emotional empathic skills enabling her to take his foibles with a grain of salt for purposes of maximizing security for her offspring.
Even if love and hate are two sides of the same heterosexual coin, there is more to consider. Obviously partners remain together well after their sex drives abate. And, as society continues to advance the cause of human rights, the state and various other agencies provide protection for men and women. Thus unless the female’s need for protection and the male’s need to provide protection are genetically hard-wired (a rather unlikely scenario given the plasticity of the human brain), other factors would have to be considered.
The following discussion does just that. It is based on the notion that a serial killer’s behavior, formation of attitudes and emotional disposition obeys the same principles outlined in behavior theory, particularly when cognition is included in the theoretical construct.
LOGIC, AGGRESSION AND REPETITIOUS BEHAVIOR.
People commit violent acts for various reasons, one of which has to do with our neuro-evolutionary potential. In the broadest context, killing is an adaptive behavior that enables a species to defend its territory and feed its young. In a somewhat ironic twist, nature appears to see death and life as co-dependent components. In order for organism x to live, organism y must die. No matter how advanced and humane society becomes we will never be able to alter that basic biological equation. Because killing and aggression are necessary to survival we have brain circuits in sections of the midbrain that prompt aggressive behavior. For example the research of Delgado (1978) demonstrated that even in the absence of a psychological event stimulation of an area in the limbic area known as the amygdala would elicit aggressive behavior. It is obviously designed for that purpose and theoretically anyone who experienced excessive or prolonged stimulation in that brain site would be disposed to violent behavior on a regular basis. By the same token, Delgado found that if stimulation of the amygdala was abruptly discontinued, aggression could be attenuated immediately.
Yet there is no evidence to support the idea that serial killers have limbic dysfunction so while aggression is an evolutionary staple, the etiology of serial murders might come from a different source.
To determine how such behavior could occur in the first place, one can begin by discussing aggression in a psychological context. Violent behavior results from frustration. Goal frustration can lead to specific arousal patterns conducive to harming others. Yet while we all become frustrated and angry few of us become serial killers. Thus one cannot assume a direct correlation between frustration (sexual or otherwise) and serial killing.
Another cause of aggression is direct provocation, as for example when one person says or does something to provoke an aggressive act. The “manslaughter scenario” happens more often in human society but it is generally not a habitual act. Why? Because it is fueled by temporary circumstances and psychosomatic arousal that eventually subsides. Thus one cannot say that external stimuli create a disposition to kill on a periodic basis unless the stimulus is ongoing.
That would seem to shift the argument from a focus on aggression to a focus on compulsivity. Because the serial killer commits the act regularly his behavior might come under the clinical rubric of a compulsion, obeying essentially the same psychodynamics as any compulsion. Through that line of reasoning, one could develop a plausible explanation of etiology.
While it would be foolish to ignore prime aspects of life such as sex and aggression neither appear to be singularly antecedent to periodic murders. If serial killers murdered for sexual gratification one might expect young males like Bundy to commit the act in concert with their sex drive. The patterns do not typically conform to such a schedule. In fact it is not uncommon for the offender to begin slowly – killing twice a year, then escalating to twice a month. As a corollary one could ask how he and other offenders satisfied themselves sexually when unable to find a victim.
If married, did they engage in sexual relations often enough to attain satisfaction? If so, what would be the sexual impetus behind the murderous act? If they murdered strictly out of anger, for example after encountering a female with a certain look who provoked thoughts of past rejection (as was partly the case with Bundy, whose victims all looked much like the girl who broke of their engagement) then one could ask what restraint mechanism kept them from taking more victims. For example a serial killer could roam around for months and occasionally come across potential victims. At least some of these potential victims would be vulnerable with respect to physical stature, time and place. Yet he might not choose to target all of them. Why does the offender not react in the moment? Which victims are given reprieve? Which are not, and why?
The uncertainty implied in that scenario leads one to infer that, as mentioned above, the prime antecedent is internal and emotionally-driven. Then the question becomes, what internal process could take time to develop, include aggressive, sexual and compulsive components? One psychic element has the potential to incorporate all three.
RESTORATION THROUGH NIHILISM
Murder is an act of aggression – symbolism notwithstanding. But what is aggression? When defined operationally it typically refers to overt, destructive acts that inflict harm or damage on persons and/or property. In psychic terms it is much more than that. Freud viewed aggression as a manifestation of thanatos, the death instinct. His assumption was that all organisms tend toward a state of entropy, with death being the natural endpoint of all things. In line with entropy theory, he believed only libidinal energy could postpone that inevitable outcome. His presumption was that a person engaging in aggressive acts was on an entropic downswing typified by low libidinal resources. This of course implies a close correlation between depression, suicide and murder. In Freud’s scenario, it would be fairly common for killers to take their own lives after committing a murder – as occurred with the mass murders by Seung-Hui Cho at Virginia Tech.
Yet most serial killers do not appear to be self destructive. That is where Freud’s contention is questionable. Indeed one could argue quite the opposite, specifically that aggression is, like sex, restorative rather than entropic.
That brings us back to the true nature of aggression. It is ultimately an act that eliminates an aversive state, a control mechanism that works by various strategies. It does so physiologically by cushioning the body with neuro-chemicals that override pain and fear, making one stronger and faster, and enhancing one’s singular focus on threat. It does so psychologically by removing objects in the outside world that are a source of duress. In the context of the latter, the primary purpose and nature of aggression is nihilistic. Despite its emotional connotations, it is based on the simplest of logical paradigms. To wit:
Object x is bothering me which produces an extremely unpleasant feeling that must be terminated or “corrected.” In order to adapt, i.e “correct” the situation I must act in such a way as to remove or erase that object. Once I do that my emotional stability will be restored.
If the object is a concrete thing one “erasure” will suffice. If it has ongoing psychological components such as fantasy, cognitive dissonance and memory, poses a threat to identity – and to the idea of one’s very existence, it might have to be dealt with periodically. Moreover its antecedent would be in the form of thoughts, images, and periodic appraisals emanating from one’s own mind.
Translated into common parlance, the serial killer’s acts might well be driven by periodic, compulsive relief-seeking whereby the habit strength of the act increases with the provision of feedback - thus the escalation. In that context it would be viewed as virtually appetitive, as a process of “undoing” and it could be described as a set of behaviors operating on a negative reinforcement schedule.
The feelings associated with this process are ultimately visceral, with perhaps little cognitive backdrop or even post-justification; thus the offender’s inability to describe his motivation. It would be similar to asking a person why he removed his hand from a hot stove. He might say…because it terminated the burning sensation… but he would not likely provide an existential reason for the behavior. In effect there is no verbal explanation and the simplicity with which serial killers seem to view their actions suggest their motivation might emanate from negative feedback, such that increasing arousal, conflict and duress and in effect self-obliteration must be countermanded by termination of the aversive stimulus (in this case the victim). In that context the act resembles obsessive-compulsive pattern more than simple aggression or even a need for notoriety – which is often presumed of most serial killers.
A compulsion generally functions to provide relief from an uncertain set of circumstances through the process of mega-control, ie. doing something with such fervor and regularity so as to preclude any further uncertainty.
In reviewing the lives of the most notorious serial killers the uncertainty factor seems to stand out. Jeffrey Dahmer became fascinated with death in his early teens. He had a history of exposing himself to young boys and masturbating in front of them. He was not a declared homosexual, indeed was disdainful of gays. Yet for a short time he joined a gay movement in Wisconsin. His sexual identity and sense of self were severely confused and this played a destructive role in other aspects of his life. His military experience was brief. He had trouble finding and holding jobs, making friends. To him people, who were prompted intolerable desires (young boys) posed a threat to his sense of self so severe as to override whatever private, non-violent, fantasy-laden defense mechanisms he might have relied on to maintain internal stability prior to embarking on his murderous rampage. He reached a point at which his internal compass, his sense of self were on the verge of entropy and decided corrective, nihilistic behavior was called for.
Dahmer’s rituals included carving up bodies. Why this act? Perhaps because it was the ultimate form of undoing that converted a personified threat into to a compartmentalized, impersonalized “something,” no more threatening than bacteria in a Petri dish. His act of dissembling the whole of the person might have been a form of relief-seeking. Once the person was depersonalized, ie. rendered piecemeal, Dahmer felt a sense of relief. No longer did he have to concern himself with the nihilistic effect live young boys had on his sense of self. If they lived, he became a non person. If they died his personhood was restored.
Bundy’s behaviors were similar. While he did not apparently have to deal with homosexual panic, he did have to deal with an uncertain identity. It began when he discovered that he was a bastard child (possibly the product of the rape of his real mother by his grandfather) It created a personal void. The fact that his fiancé broke off their relationship around the same time created a kind of perfect psychological storm. While he was not psychotic he might well have experienced a disintegration of the ego. In what amounted to a horrific balancing act he targeted victims whose existence threatened to erase completely his point of self reference. To restore internal stasis he had to “erase” them instead. In other words, like many serial killers he operated by a mechanism that could be called a destructive reciprocity.
Like all males he needed love from females -as he stated in court. However love was too much of a risk, his identity too irrevocably fractured by the existence of living, breathing women. To him love could only come with a caveat. He could only obtain love by having intercourse with dead bodies, as per the female non-personhood scenario. That might explain his periodic visits to sites where he placed his victims, and the fact that he often put makeup on the faces of the deceased then engaged in sex with their bodies until, over time, they no longer had enough anatomical substance for that to happen.
The uncertainty/mixed identity factor might also have played a prominent role in the emergence of Gacy. He was married, had children, but in young adulthood was also prone to engaging in sexual acts with teenage boys. In his case there were other factors, including an abusive father, a head injury and his being sexually molested by an older man during his childhood. However a point of extreme irresolution over sense of self and a compulsive need to erase the source of that confusion might have been precipitating factors in the killing. Gacy’s paradigm might have been…As long as young boys exist I cannot exist. Only nihilism can provide the relief-reinforcement needed to restore a sense of self with respect to the way I choose (need) to see myself.
HUNTING/STALKING AND NIHILISM
Aggression correlates with nihilism in such a fundamental way that they are arguably indistinguishable. In a biological context one could ask if “anger” is really what we think it is. For example, when predators hunt, the point is really to incapacitate their prey. (A carnivore cannot eat a moving target). Moreover all predators understand instinctively that hunting is an energy tradeoff. On some level they must consider whether the energy derived from eating prey is enough to compensate for the energy expended on the hunt. Unless there was a significant caloric differential there would be no point in hunting. Thus hunting strategies must entail some degree of convenience.
That has implications for the human predator. Perhaps like his animal counterpart he is less interested in inflicting pain or seeking revenge than in simply completing the act, so as to terminate the threat and the duress, which for the animal is a state of hunger and for the serial killer, a fear of personal disintegration. Both seek to restore stability. Both operate by a negative reinforcement paradigm. For both the goal is nihilism – to kill in order to remain alive (or psychologically intact).
In that context clinicians and law enforcement personnel interested in discovering the motives of a serial killer might be better off asking not why the offender committed the act but how the offender would have felt had he not committed the act. Perhaps a statement issued by Rader in a prison interview is indicative. He stated that in one instance he had targeted a sixty three year old woman but was unable to lure her in. As a result, he experienced what could be described as a catastrophic emotional reaction. Clearly, despite the bravado and casuistry implied in his letters to the press his killing was borne of desperation. It appears he needed to terminate the lives of his victims to restore his own psycho-stasis.
TARGET SELECTION- WHY THOSE PEOPLE?
When it comes to serial murder, the obvious question in everyone’s mind (particularly that of the victims’ loved ones) is…why, my daughter, son, or wife? One suspects the agony of not knowing is almost as severe as the loss itself. With regard to an explanation, the threat-removal/negative reinforcement hypothesis might provide a partial answer. One possible scenario is as follows:
The offender engages in introspection periodically – as we all do with time on our hands. He goes “scouting,” looks around at others. Occasionally some person foments an internal reaction so substantial as to require erasure of that person. The more vibrant and content and/or threatening the potential victim the more diminished is the killer’s existence. Then comes agitation, a drive to remove the person-stimulus and a subsequent plan to restore stasis. In the killer’s mind he and the victim have an inverse relationship that can only be rectified by the victim’s demise.
Bundy might have been so devastated by rejection as to experience sub psychotic ego-disintegration. It might have been manifest as a downward slide toward non-person-hood, perhaps compounded by an initially exalted sense of self arising from his doting grandmother. Scouting around, seeing slender, dark haired women, confident and content in their circumstances threatened to erase Ted’s sense of Ted completely. It required a drastic compensatory measure. Thus it might not have been poor up-bringing that led to nihilism and a life of extreme violence but an incongruous juxtaposition of circumstances featuring special treatment by his aunt/mother played against his discovering he was a bastard child and the rejection by his fiancé.’
Meanwhile the BTK killer stood in court, virtually boasting about the heinous cruelties he heaped upon a mother and her children. No remorse, no embarrassment – as if he felt his actions were somehow justified. The only way one can override guilt vis a vis social mores in adopting such an outrageous attitude is by an overriding sense that the acts were necessary – in this case to his own psychological integrity.
For some reason, the very existence of BTK’s victims threatened his own. To him circumstances warranted a mechanistic, reductionist handling of the matter. His victims were not considered actual people, just obstacles that had to be removed to preclude the threat of ego disintegration.
If the above contentions have merit, investigatory procedures purporting to identify the motives of incarcerated serial killers might be best served by looking for person-stimuli fomenting points of severe instability. A kind of “social Rorschach test” could easily be developed, featuring vague images of different types of people to see how the offender responds. Would he choose only small (avoidant) details for images reminiscent of young women, authority figures, young children? Would he superimpose movement, shading and texture determinants over such images, suggesting a need to impose his own percepts onto the person-stimulus; thus implying a need to over-control that image? Moreover, if his perception of control had nihilistic implications could investigators and clinicians then infer a causal relationship between the offender’s proneness to violence and the victim’s very existence?
A linguistic version of this could be accomplished with an adapted Sentence Completion projective instrument. The format could include “sentence stubs” lending themselves to nihilistic themes, particularly with regard to undoing, aggressive actions leading to a sense of relief.
Finally the use of Galvanic Skin Responses and other psycho-physiological instruments might be useful in establishing cause-effect, negative reinforcement patterns. Any and all of those possibilities could help provide a capacity to understand and predict such behavior at earlier ages.
Unfortunately this article does not address prevention and that is obviously a key issue. However it does suggest specific directions for investigation and diagnostics that might provide answers in the future.
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