Descending into minds that people view as belonging to despicable monsters is a requirement for individuals who search for or attempt to understand serial killers. The serial murderer Jeffrey Dahmer would go to bars in Milwaukee, Wisconsin, and pick up young men, sometimes telling them he was a photographer and luring them back to his apartment with an offer of money to be his model. He would then drug their drinks to subdue them so that they would be easier to strangle. However, those factors did not tell investigators the emotional core of his killing, they were simply the modus operandi (MO) of the crime. MO includes victim type, how the criminal approached or overcame his victim, tools used, and the time and place that the crime occurred.
More revealing is what has been called a killer's "signature," which has been defined by John Douglas as "a personal detail that is unique to the individual, why he does it: the thing that fulfills him emotionally" (Douglas 1997, p. 26). John Douglas, the first full-time profiler at the behavioral science division of the Federal Bureau of Investigation Academy in Quantico, Virginia, thinks the killer's signature is a better guide to behavior than his MO. While the MO may change as the killer comes up with a better technique, the emotional reason he commits the crime does not change. In Dahmer's case his murder signature showed the sadistic sexual satisfaction and control of living with his victims' bodies. In his case, some of these behaviors included engaging in sex with the bodies, cutting up the victims and cannibalizing body parts such as the heart, pulling muscles from the bone and wearing them on his own shoulders, painting the skulls to put over his bed, and storing one victim's head in the refrigerator.
Characteristics of Serial Murder
What is serial murder? The British author John Brody first used the term in 1966, and the National Institute of Justice defined serial murder in 1988 as "a series of 2 or more murders, committed as separate events, usually, but not always, by one offender acting alone" (Newton 2000, p. 205). Another perspective is that of Steve Egger, who uses six characteristics in his definition of serial murder: (1) There are a minimum of two murders; (2) the killer and victim are unrelated; (3) the murders have no direct connection to each other and occur at different times; (4) the murders usually occur at different locations; (5) victims may have characteristics in common with earlier or later victims; and (6) the murders are not committed for material gain but for gratification based on fantasies.
Several of these characteristics are debatable. The material gain motive is more common with the female than the male style of serial murder, thus Egger's definition could be seen more as serial signature murder. Also, individuals such as Edmund Kemper, who killed his grandparents and mother, and Henry Lee Lucas, whose mother was his first victim, are generally classified as serial killers. The criminologist Eric Hickey states that most researchers define serial killers as having three to four victims, but also includes in his database of serial killers some individuals who "killed only two victims but were suspect in other slayings or in which evidence indicated their intent to kill others" (Hickey 1997, p.27). The problem with using a definition based strictly on three victims omits the two-time signature killer who has obsessive qualities and would be expected to continue to kill.
Serial murder differs from mass murder in that mass murder involves killings of four or more victims in the same general area and occurs as one event in a short period of time. The mass murderer "appears to give little thought or concern to his or her inevitable capture or death" and may give him- or herself up or commit suicide if not killed by police (ibid., p. 7).
Characteristics of the Serial Killer
According to Hickey's 1997 database of approximately 399 serial killers, the average age of the murderer at the time of the first killing was 27.5 years, and they typically were white males. Criminologists James A. Fox and Jack Levin (2001) found that males made up more than 90 percent of the sample. Seventy-three percent of male offenders were white, 22 percent were African-American, and the remainder were of different ethnic groups. Fox and Levin report that the researcher Grover Godwin's 1999 database of 107 serial killers revealed an average age of thirty. Ninety-five percent were males, 5 percent were females, and 16 percent were African-American. Godwin also found that only 4 percent of his sample graduated with a bachelor's degree, while most were employed in blue-collar jobs. Victims were 67 percent female, with children, prostitutes, and the elderly as other preferred victim categories, although 20 percent of Godwin's sample were males who had additionally been raped by their attackers.
In 1992 the researchers Robert Ressler, a veteran of the FBI who served as founder of the FBI's Violent Criminal Apprehension Unit; Ann Burgess and John Douglas interviewed thirty-six convicted, imprisoned, sexual murderers who had a total of 118 murder and attempted murder victims among them. The interviews with the sexual murderers showed very active, violent, sexualized fantasies, which focused on killing until the first murder occurred and perfecting the killing after the first murder had occurred. The researchers were surprised by the lack of positive childhood fantasies remembered by the offenders. They noted progression in seven of the offenders from conscious awareness of a fantasy to actually acting out the fantasy within only a year. They saw clear behavioral progressions as well. Numerous authors have cited the childhood predictive behavior for serial killers of torturing animals. Many serial killers had been arrested, or had been in mental hospitals, for less serious behaviors before the serial killing began.
Organized vs. Disorganized. There are several typologies of serial killers. Ressler, Burgess, and Douglas viewed them either as "organized" or "disorganized" based on crime scene information. The organized killer plans the murder, chooses a stranger as a victim, then engages in limited conversation with the relatively personalized victim. The crime scene is not sloppy, but controlled, as is the victim, who suffers aggressive acts before death. The weapon is not present, nor is the victim's body. The crime scene for a disorganized murderer, on the other hand, is a spontaneous offense with either the victim or the area, or both, known to the perpetrator. There is very little conversation with a depersonalized victim, who suffers sudden violence. A few personal qualities of the organized criminal are good intelligence, high birth order status, some social competence, and the use of alcohol with the crime. The disorganized killer has average intelligence, is socially immature, has lower birth order status, uses alcohol minimally, and is more likely to be psychotic than an organized killer.
Some killers have qualities of both types, such as Jack the Ripper, who operated in 1888 in Whitechapel, the east end of London. This area of poverty and misery saw the savage assaults of Jack the Ripper on a series of prostitutes. Because his true identity was never officially revealed, John Douglas profiled the killer a century later, and the biographer Phillip Sudgen believes Douglas would have labeled him "disorganized." Yet Sudgen points out that this murderer also had some organized qualities such as the ability to hold a conversation with potential victims and his typical removal of weapons and clues.
Male vs. Female. Hickey reviewed differences between male and female serial killers. Results show female serial killers are more likely to kill husbands, relatives, or people in hospitals or nursing homes where they work; murder in one specific place; poison the victims; and report money to be a motive. Males are more likely to kill strangers, be geographically mobile, torture or mutilate more often when killing, and report a sexual motive. Most females thus meet the definition of the National Institute of Justice as serial murderers but do not meet Egger's definition with its additional parameters of the killer and victim being unrelated and a murder not committed for material gain but for fantasy gratification.
The Psychological Phases of Serial Killers
In 1988 the psychologist Joel Norris described the psychological phases that serial killers experience. Norris worked on the defense teams of several convicted killers from Georgia and completed 500 interviews with such individuals, during which he identified the following phases.
The killer begins with an aura phase, in which there is a withdrawal from reality and a heightening of the senses. This phase may last anywhere from several moments to several months and can begin as a prolonged fantasy, which may have been active for a short time or for years. The killer may attempt to medicate himself with alcohol or drugs.
The trolling phase consists of the behavior patterns that a particular killer uses to identify and stalk his victim. Norris described how Ted Bundy strapped his arm in a sling and asked for help with books, packages, or even the hull of a sailboat to lure the victim into his car. Some victims escaped and said he never seemed out of control until the moment he actually attacked them.
The wooing phase is that time period when most killers win the confidence of victims before luring them into a trap. The capture phase may include the locking of a door or a blow that renders the victim helpless. The killer savors this moment. Norris described the murder phase as the ritual reenactment of the disastrous experiences of the killer's childhood, but this time he reverses the roles.
The next phase Norris described is the totem phase. After the kill, murderers sink into a depression, so many develop a ritual to preserve their "success." This is why some killers keep news clippings, photographs, and parts of the victims' bodies, or eat parts of the victims, wear their skin, or show parts of victims' bodies to later victims. The trophy is meant to give the murderer the same feelings of power he experienced at the time of the kill.
The last phase is the depression phase. A victim, now killed, no longer represents what the killer thought he or she represented, and the memory of the individual that tortured the murderer in the past is still there. Ressler compares the murder to a television serial with no satisfactory ending because the serial killer experiences the tension of a fantasy incompletely fulfilled. In each subsequent murder, he attempts to make the scene of the crime equal to the fantasy. Norris notes that there is an absence of the killer's sense of self and, during this phase, the killer may confess to the police before the fantasies start once more. However, because victims are not seen as people, recollections of murders may be vague or viewed as the killer having watched someone else. They may have a memory for tiny details about the murder, which is dissociated from the event as a whole.
Psychological, Social, and Biological Factors in the Serial Murder
Psychological factors in the development of serial murder have sometimes included obvious abuse or emotional isolation in childhood. An example of the obviously abusive stands out in Henry Lee Lucas's prostitute mother hitting him for years with broom handles, dressing him as a girl for school, and forcing him to watch her having sex with men who would then be violent toward him. In such cases, the child appears to identify with the aggressor and replay a childhood victimization, this time as the aggressor. But not all cases show obvious massive family dysfunction. Many cases, however, according to Ressler and his fellow researchers Ann Burgess and John Douglas, do show loss of a parent or parental rejection. Robert Keppel and William Birnes describe the formation of the diphasic personality, in which a person's life develops two phases. One phase is the fantasy life where the child has complete control, while the other phase is the shell that walks through the real world and has little energy or effort committed to it. The child is emotionally isolated with his fantasies.
From a social construction point of view, Hickey describes a trauma-control model of the serial killer. While head injury or brain pathology may be predisposing factors, the eventual offender responds to traumatization in the formative years in the negative way of having low self-esteem and increasingly violent fantasies. Traumatic experiences and feelings from the past may be dissociated from conscious feelings, and the adult offender may aid an altered state of consciousness by facilitators such as alcohol, pornography, or drugs. Finally he commits murder as a way of regaining control and may initially feel reinforced before the low self-esteem sets in again.
Biological causes of crime were hypothesized by Hans Eysenck, who believed that criminality resulted from a nervous system distinct from that of most people, and that extroverts were more likely to be involved in antisocial behavior. J. A. Gray proposed a behavioral inhibition system as the neural system underlying anxiety. This system teaches most people not to make an antisocial response because of anxiety and is called passive avoidance learning. The researcher Don Fowles continued this concept with the idea that criminal personalities have deficient behavioral inhibition systems, therefore will proceed to make the anti-social response. The second half of Gray's model is the behavioral activation system, which causes reward-seeking behavior and active avoidance of punishment, such as running away. Fowles believes this system is normal in the criminal personality. Gray's theory also says there is a nonspecific arousal system receiving excitatory inputs from both systems.
Similar ideas may be viewed directly from the brain. In a 1997 article in the Journal of Psychoactive Drugs, the researcher Daniel Amen reported findings with Single Photon Emission Computerized Tomography (SPECT) brain imaging, which measures metabolic activity and cerebral blood flow patterns to examine differences in the aggressive brain. He examined forty aggressive adolescents and adults from a psychiatric population that physically attacked someone or destroyed property within six months of evaluation, and compared them to an age-, sex-, and diagnosis-matched control group of forty psychiatric patients who had never had reported problems with aggression. No person was included in the study who had a history of a substance abuse problem in the last year or a history of head injury involving loss of consciousness.
Amen found aggressive individuals show significant differences from nonviolent individuals. First, there is decreased activity in the prefrontal cortex; decreased functioning would result in less impulse control, less ability to focus attention, and poor judgment of highly charged situations. He found increased activity in the left side only of the basal ganglia and limbic system. Among multiple complex functions, he noticed that overactivity in the basal ganglia is associated with anxiety, and overactivity in that part of the limbic system is associated with negative mood and a higher chance of violent behavior. He found increased activity in the temporal lobes, which, among other functions, have been connected to temper outburst and rapid mood shifts, especially noted for the left temporal lobe. He found increased activity in the anteromedial portions of the frontal lobes (anterior cingulate area), which, among other functions, results in obsessive inability to stop thinking about negative events or ideas. In his 1997 publication, Amen discusses how correct medication can improve some of these abnormalities and, along with therapy, improve problem behavior. He has also found that the use of alcohol results in overall decreased brain activity, and chronic alcoholism is associated with reduced metabolism, especially in the frontal and temporal regions of the brain. These are the same regions involved in violent behavior. Interestingly, Ressler and colleagues specifically listed alcohol use during the murder as one of the characteristics of the organized serial killer.
Violence has also been connected to a variety of serotonin abnormalities as well as reduced glucose metabolism shown by positron emission tomography. In 1997 the scholar Adrian Raine and colleagues examined glucose metabolism in forty-one murderers pleading not guilty by reason of insanity, compared to an equal number of age- and sex-matched control subjects. The murderers showed reduced glucose metabolism in the prefrontal cortex, superior parietal gyrus, left angular gyrus, and corpus callosum. The left hemispheres of their brains had lower activity than the right in the amygdala, thalamus, and medial temporal lobe.
Research has identified certain brain dysfunctions, parental loss or rejection, and the development of the diphasic personality and the trauma control model as potential factors in the development of the serial killer. In the future, identifying the diphasic, emotionally isolated child and helping him or her to connect with people could potentially occur in the school. Perhaps brain scans as well as school-based behavioral evaluations could indicate those people who might benefit from psychotherapy, social skills interventions, medication, or some combination of the above to prevent or control their aggressiveness. A society with the skills and the willingness to finance such a possibility would have to make careful decisions about the freedoms of the people it labeled as well as the rights of the public. Yet deinstitutionalization of the mentally ill, as flawed as it is, took hundreds of thousands of people out of hospitals and gave them a less restrictive life. Perhaps a similar, but well-managed, outcome could be the future of a safe public and of the murderers society must lock away.
See also: AIDS; Homicide, Definitions and Classifications of; Mass Killers
Amen, Daniel, Matthew Stubblefield, Blake Carmichael, and Ronald Thisted. "Brain SPECT Findings and Aggressiveness." Annals of Clinical Psychiatry 8, no. 3 (1996):129–137.
Amen, Daniel G., Stanley Yantis, John Trudeau, Matthew Stubblefield, and Jonathan Halverstadt. "Visualizing the Firestorms in the Brain: An Inside Look at the Clinical and Physiological Connections between Drugs and Violence Using Brain SPECT Imaging." Journal of Psychoactive Drugs 29, no. 4 (1997):307–319.
Douglas, John, and Mark Olshaker. Journey into Darkness. New York: Pocket Books, 1997.
Fowles, Don C. "The Three Arousal Model: Implications of Gray's Two-Factor Learning Theory for Heart Rate, Electrodermal Activity, and Psychopathy." Psychophysiology 17, no. 2 (1980):87–104.
Fox, James A., and Jack Levin. The Will to Kill. Boston: Allyn and Bacon, 2001.
Gresswell, David M., and Clive R. Hollin. "Multiple Murder: A Review." British Journal of Criminology 34, no. 1 (1994):1–14.
Hickey, Eric. Serial Murderers and Their Victims, 2nd edition. Belmont, CA: Wadsworth, 1997.
Keppel, Robert D., and William J. Birnes. Signature Killers. New York: Pocket Books, 1997.
Levin, Jack, and James A. Fox. "Serial Murder." In Deadlines: Essays in Murder and Mayhem. Boston: Allyn and Bacon, 2001.
Newton, Michael. The Encyclopedia of Serial Killers. New York: Checkmark Books, 2000.
Norris, Joel. Serial Killers. New York: Anchor Books/Doubleday, 1989.
Raine, Adrian, Monte Buchsbaum, and Lori LaCasse. "Brain Abnormalities in Murderers Indicated by Positron Emission Tomography." Biological Psychiatry 42, no. 6 (1997):495–508.
Ressler, Robert K., Ann W. Burgess, and John E. Douglas. Sexual Homicide: Patterns and Motives. New York: Free Press, 1992.
Ressler, Robert K., and Tom Shachtman. I Have Lived in the Monster. New York: St. Martin's Press, 1997.
Ressler, Robert K., and Tom Shachtman. Whoever Fights Monsters. New York: St. Martin's Press, 1992.
Seltzer, Mark. Serial Killers: Death and Life in America's Wound Culture. New York: Routledge, 1998.
Sudgen, Phillip. The Complete History of Jack the Ripper. New York: Carroll & Graf Publishers, 1995.
SANDRA BURKHALTER CHMELIR
"Serial Killers." Macmillan Encyclopedia of Death and Dying. . Encyclopedia.com. (July 12, 2018). http://www.encyclopedia.com/social-sciences/encyclopedias-almanacs-transcripts-and-maps/serial-killers
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Serial killers, those who kill more than once, pose a special problem for crime investigators because the their motives are often far less obvious than those of the person who commits a single homicide. Investigators describe three types of killer who commit multiple murders. The mass murderer kills several people at one time. Often these killers turn out to be disgruntled employees who show up at their places of work with shotgun in hand, bent on revenge. Spree killers often go on rampages with knives or guns, killing one person after another. Such people often have serious mental health problems. The serial killer, however, dispatches one victim at a time, with a time interval that may be as long as several years between each murder .
The "Washington Sniper" (aka, "Beltway Sniper" or "D.C. Sniper") killed ten people within a three-week period in the Washington, D.C., area in 2002. Originally thought to be a lone gunman, the killers turned out to be Gulf War veteran John Allen Muhammad and 18-year-old Lee Boyd Malvo, who were both convicted of capital murder. The media quickly labeled them "spree killers." Forensically speaking, however, they are probably more accurately described as a serial killers.
The serial killer tends to prey upon people at random. Usually, the attacker does not know the victims personally. The Federal Bureau of Investigation (FBI ) Behavioral Science Unit developed the concept of psychological profiling in the 1960s to aid in the pursuit of serial killers and to let police know what kind of man (serial killers are nearly always men) is instigating the crimes.
Despite attempts by authorities to profile and find serial killers, some killers can continue killing and elude authorities for years. The so-called Green River Killer murdered at least 48 victims over a span of 16 years, from 1982 to 1998. The confessed murderer, Gary Leon Ridgway (now serving a life sentence), claimed that strangling young women was his "career."
Despite all the work that has been done on the psychology of the serial killer, forensic psychologists and psychiatrists are still far from understanding such people. Although it may be easier to comprehend someone who kills out of greed or revenge, the work of a serial killer is so far removed from normal behavior that most people have little understanding of his motives.
Many serial killers are psychopaths. Psychopathy, or anti-social personality disorder, is not considered completely curable. There is even debate by some scientists as to whether it is a mental illness at all. The hallmark of the psychopath is an extreme lack of guilt or empathy for others, which means the serial killer can carry out terrible crimes without emotional distress. Studies of serial killers in prison and evidence gathered from those who know them suggest that many of these murderers were the targets of physical, psychological, or sexual abuse in early childhood. This may lead them to build a world based on fantasy as a protective measure. These fantasies are then acted out in the course of a violent crime, often with a sexual context. The killer feels satisfied after the crime and then relaxes for a while. However, it is only a matter of time before the fantasies push them toward the next killing.
As the homicides mount, it becomes increasingly urgent for police to track down the killer. Also, as the killings mount, so too does the evidence, no matter how clever the killer may consider himself to be. As he continues, he may become careless or complacent, and the chances of his capture increase.
The forensic psychiatrist uses evidence from the crime scene to build a psychological profile of the serial killer. One categorization that has been found useful is to decide whether the investigators are dealing with an organized or a disorganized killer. If the crime scene suggests the murder was carefully planned and executed, then the killer may be a man of average to high intelligence who has a stable social network. He may be married with a family. He may also be employed. Living a "normal" life on the surface requires a degree of self-control, which manifests itself in the way the crime is carried out. Sometimes, though, the organized offender does lose control in the actual attack when the fantasy motivation takes over. In such cases, a violent or frenzied attack may occur, yet there may also be careful attempts to conceal or destroy evidence.
The disorganized offender leaves a mess at the crime scene. He may use any weapon that is available to strike out and makes little effort to cover his tracks. This lack of planning and control often suggests low intelligence. He is likely to be unemployed and may be a bit of a loner with few friends. The attack may be marked by excessive violence and could also include sexual contact with the victim after death. The disorganized serial killer often turns out to have a history of mental illness.
A number of other factors can be added to the profile. Many serial killers are young adults in their twenties or thirties. They tend not to cross racial lines. White killers tend to kill white victims; black killers tend to kill blacks. Many kill close to home the first few times, but then start to move farther away. Serial killers are eventually often highly mobile, which can make the logistics of catching them difficult.
Of particular interest to those investigating serial killers is what is taken from the scene or from the victim. In most crimes, the perpetrator will take items of monetary value, like cash or jewelry. They may also take evidence, such as a weapon. The serial killer often takes something known as a trophy or souvenir, of no obvious value except to him in his fantasy world. The item is known as a trophy if it is seen as a symbol of achievement and a souvenir if it is to remind the killer of the crime.
Trophies and souvenirs are an important part of the killer's modus operandi ("method of operation," or M.O.), the name given to the particular tools and strategies that distinguish the killer's work. The M.O. includes factors such as the location of the crimes, the tools used, the time of day, the alibi, and any accomplices involved. The M.O. may, of course, evolve over time as the killer becomes more experienced. The investigators will be particularly interested in any details that are unique to that killer, such as leaving a note behind. They will also look for the signature of the crime. Trophies and souvenirs can be part of the signature, as can mutilating or having sex with the corpse, or placing the body in a certain position.
Victimology, the study of the victim, can be crucial in tracking down a serial killer. The investigators need to know what it was about that particular person that attracted the killer. Was the victim truly chosen at random or had the person been stalked previously? The killer may have been searching for the one person who fit his fantasy and, if a common link can be found between the victims, this may be very revealing. For instance, nearly all of the victims of serial killer Ted Bundy had dark hair parted in the center.
The location of the serial killer's crimes is also of significance. Geographical profiling is based on the premise that the killer will operate in a zone where he feels comfortable. This may be near home or, alternatively, far away from it, depending on his psychological make-up. Location is not just where the crime was committed, but is also where the victim was abducted and where the body was taken and left after the crime. Establishing a geographical profile can be challenging if the victim was a prostitute, for instance, or someone who might not be missed by relatives or co-workers for a while. The Yorkshire Ripper killed several prostitutes in the United Kingdom from 1977 to 1981, and the difficulty of tracking the victims' movements sometimes hindered the investigation. Sometimes bodies are dumped in remote places and may not be found for some time. In such cases, a forensic anthropologist may be called in to judge the times of death so the order in which victims were killed can be determined.
The world's most prolific serial killer was Dr. Harold Shipman, a British physician who took his own life in prison in 2004. He may have been responsible for up to 300 deaths, but the true figure will never be known as he always denied the killings. Prior to this, the so-called "Monster of the Andes," Pedro Lopez, held this dubious distinction, having been convicted of 57 murders in 1980. He may have killed many more; his victims were young girls in Colombia.
Despite his notoriety, Shipman was, in many ways, an unusual type of serial killer. His victims, many of whom were elderly women, met their end through morphine injections, one of the main methods of assisted suicide, which some believe to be a compassionate act. He was well known and liked in his community, and there was no obvious motive for the crimes. Some psychiatrists have suggested Shipman disliked older women, or that he was trying to re-enact the death of his mother. Others believed he gained pleasure from the power of life and death that he could exercise as a doctor. Shipman may have begun to kill patients very early on in his medical career, before he had even finished training to be a doctor. Initially, it was thought he began his career as a serial killer in 1974 when he first became a family doctor. This would put the number of deaths between 216 and 260. If, however, he began to kill almost as soon as he had the opportunity, then at least 24 more deaths, and maybe more, could have been at the hands of Shipman.
see also Bundy (serial murderer) case; Psychological profile; Psychopathic personality.
"Serial Killers." World of Forensic Science. . Encyclopedia.com. (July 12, 2018). http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/serial-killers
"Serial Killers." World of Forensic Science. . Retrieved July 12, 2018 from Encyclopedia.com: http://www.encyclopedia.com/science/encyclopedias-almanacs-transcripts-and-maps/serial-killers