When defining serial killers, researchers generally use "three or more murders" as the baseline, considering it sufficient to provide a pattern without being overly restrictive. Independent of the number of murders, they need to have been committed at different times, and are usually committed in different places. The lack of a cooling-off period (a significant break between the murders) marks the difference between a spree killer and a serial killer. The category has, however, been found to be of no real value to law enforcement, because of definitional problems relating to the concept of a "cooling-off period." Cases of extended bouts of sequential killings over periods of weeks or months with no apparent "cooling off period" or "return to normality" have caused some experts to suggest a hybrid category of "spree-serial killer".
In 2005, the FBI hosted a multi-disciplinary symposium in San Antonio, Texas, which brought together 135 experts on serial murder from a variety of fields and specialties with the goal of identifying the commonalities of knowledge regarding serial murder. The group also settled on a definition of serial murder which FBI investigators widely accept as their standard: "The unlawful killing of two or more victims by the same offender(s) in separate events". Serial homicide researcher Enzo Yaksic found that the FBI was justified in lowering the victim threshold from three to two victims given that serial murderers from these groups share similar pathologies.
The majority of documented serial killers were active in the United States. In one study of serial homicide in South Africa, many patterns were similar to established patterns in the U.S., with some exceptions: no offenders were female, offenders were lower educated than in the U.S., and both victims and offenders were predominantly black.
In the 15th century, one of the wealthiest men in Europe and a former companion-in-arms of Joan of Arc, Gilles de Rais, was alleged to have sexually assaulted and killed peasant children, mainly boys, whom he had abducted from the surrounding villages and had taken to his castle. It is estimated that his victims numbered between 140 and 800. Similarly, the Hungarian aristocrat Elizabeth Báthory, born into one of the wealthiest families in Transylvania, allegedly tortured and killed as many as 650 girls and young women before her arrest in 1610.
The Ripper murders also marked an important watershed in the treatment of crime by journalists. While not the first serial killer in history, Jack the Ripper's case was the first to create a worldwide media frenzy. The dramatic murders of financially destitute women in the midst of the wealth of London focused the media's attention on the plight of the urban poor and gained coverage worldwide. Jack the Ripper has also been called the most infamous serial killer of all time, and his legend has spawned hundreds of theories on his real identity and many works of fiction.
The serial killing phenomenon in the United States was especially prominent from 1970 to 2000, which has been described as the "golden age of serial murder". The cause of the spike in serial killings has been attributed to urbanization, which put people in close proximity and offered anonymity. The number of active serial killers in the United States peaked in 1989 and has been steadily trending downward since, coinciding with an overall decrease in crime in the United States since that time. The decline in serial killers has no known single cause but is attributed to a number of factors. Mike Aamodt, emeritus professor at Radford University in Virginia, attributes the decline in number of serial killings to less frequent use of parole, improved forensic technology, and people behaving more cautiously. Causes for the general reduction in violent crime following the 1990s include increased incarceration in the United States, the end of the crack epidemic in the United States, and decreased lead exposure in early childhood.
Many serial killers have faced similar problems in their childhood development. Hickey's Trauma Control Model explains how early childhood trauma can set the child up for deviant behavior in adulthood; the child's environment (either their parents or society) is the dominant factor determining whether or not the child's behavior escalates into homicidal activity.
Family, or lack thereof, is the most prominent part of a child's development because it is what the child can identify with on a regular basis. "The serial killer is no different from any other individual who is instigated to seek approval from parents, sexual partners, or others." This need for approval is what influences children to attempt to develop social relationships with their family and peers. "The quality of their attachments to parents and other members of the family is critical to how these children relate to and value other members of society."
Wilson and Seaman (1990) conducted a study on incarcerated serial killers, and what they concluded was the most influential factor that contributed to their homicidal activity. Almost all of the serial killers in the study had experienced some sort of environmental problems during their childhood, such as a broken home caused by divorce, or a lack of a parental figure to discipline the child. Nearly half of the serial killers had experienced some type of physical or sexual abuse, and more of them had experienced emotional neglect.
There have been studies looking into the possibility that an abnormality with one's chromosomes could be the trigger for serial killers. Two serial killers, Bobby Joe Long and Richard Speck, came to attention for reported chromosomal abnormalities. Long had an extra X chromosome. Speck was erroneously reported to have an extra Y chromosome; in fact, his karyotype was performed twice and was normal each time. While attempts have been made to link the XYY karyotype to violence, including serial murder, research has consistently found little or no association between violent criminal behaviour and an extra Y chromosome.
Criminologist Jose Sanchez reports, "The young criminal you see today is more detached from his victim, more ready to hurt or kill. The lack of empathy for their victims among young criminals is just one symptom of a problem that afflicts the whole society." Lorenzo Carcaterra, author of Gangster (2001), explains how potential criminals are labeled by society, which can then lead to their offspring also developing in the same way through the cycle of violence. The ability for serial killers to appreciate the mental life of others is severely compromised, presumably leading to their dehumanization of others. This process may be considered an expression of the intersubjectivity associated with a cognitive deficit regarding the capability to make sharp distinctions between other people and inanimate objects. For these individuals, objects can appear to possess animistic or humanistic power while people are perceived as objects. Before he was executed, serial killer Ted Bundy stated media violence and pornography had stimulated and increased his need to commit homicide, although this statement was made during last-ditch efforts to appeal his death sentence.
In the 1970s and 1980s, FBI profilers instigated a simple division of serial killers into "organized" and "disorganized"; that is, those who plan their crimes, and those who act on impulse. The FBI's Crime Classification Manual now places serial killers into three categories: organized, disorganized, and mixed (i.e., offenders who exhibit organized and disorganized characteristics). Some killers descend from organized to disorganized as their killings continue, as in the case of psychological decompensation or overconfidence due to having evaded capture.
Organized serial killers often plan their crimes methodically, usually abducting victims, killing them in one place and disposing of them in another. They often lure the victims with ploys appealing to their sense of sympathy. Others specifically target prostitutes, who are likely to go voluntarily with a stranger. These killers maintain a high degree of control over the crime scene and usually have a solid knowledge of forensic science that enables them to cover their tracks, such as burying the body or weighing it down and sinking it in a river. They follow their crimes in the news media carefully and often take pride in their actions as if it were all a grand project.
Often, organized killers have social and other interpersonal skills sufficient to enable them to develop both personal and romantic relationships, friends and lovers and sometimes even attract and maintain a spouse and sustain a family including children. Among serial killers, those of this type are in the event of their capture most likely to be described by acquaintances as kind and unlikely to hurt anyone. Ted Bundy and John Wayne Gacy are examples of organized serial killers. In general, the IQs of organized serial killers tend to be normal range, with a mean of 98.7.
Disorganized serial killers are usually far more impulsive, often committing their murders with a random weapon available at the time, and usually do not attempt to hide the body. They are likely to be unemployed, a loner, or both, with very few friends. They often turn out to have a history of mental illness, and their modus operandi (M.O.) or lack thereof is often marked by excessive violence and sometimes necrophilia or sexual violence. Disorganized serial killers have been found to have a lower mean IQ than organized serial killers, at 89.4. Mixed serial killers, with both organized and disorganized traits, have an average IQ of 100.9, but a low sample size.
Some people with a pathological interest in the power of life and death tend to be attracted to medical professions or acquiring such a job. These kinds of killers are sometimes referred to as "angels of death" or angels of mercy. Medical professionals will kill their patients for money, for a sense of sadistic pleasure, for a belief that they are "easing" the patient's pain, or simply "because they can". Perhaps the most prolific of these was the British doctor Harold Shipman. Another such killer was nurse Jane Toppan, who admitted during her murder trial that she was sexually aroused by death. She would administer a drug mixture to patients she chose as her victims, lie in bed with them and hold them close to her body as they died.
Female serial killers are rare compared to their male counterparts. Sources suggest that female serial killers represented less than one in every six known serial murderers in the United States between 1800 and 2004 (64 females from a total of 416 known offenders), or that around 15% of U.S. serial killers have been women, with a collective number of victims between 427 and 612. The authors of Lethal Ladies, Amanda L. Farrell, Robert D. Keppel, and Victoria B. Titterington, state that "the Justice Department indicated 36 female serial killers have been active over the course of the last century." According to The Journal of Forensic Psychiatry & Psychology, there is evidence that 16% of all serial killers are women.
Michael D. Kelleher and C. L. Kelleher created several categories to describe female serial killers. They used the classifications of black widow, angel of death, sexual predator, revenge, profit or crime, team killer, question of sanity, unexplained, and unsolved. In using these categories, they observed that most women fell into the categories of the black widow or team killer. Although motivations for female serial killers can include attention seeking, addiction, or the result of psychopathological behavioral factors, female serial killers are commonly categorized as murdering men for material gain, usually being emotionally close to their victims, and generally needing to have a relationship with the victim, hence the traditional cultural image of the "black widow".
The methods that female serial killers use for murder are frequently covert or low-profile, such as murder by poison (the preferred choice for killing). Other methods used by female serial killers include shootings (used by 20%), suffocation (16%), stabbing (11%), and drowning (5%). They commit killings in specific places, such as their home or a health-care facility, or at different locations within the same city or state. A notable exception to the typical characteristics of female serial killers is Aileen Wuornos, who killed outdoors instead of at home, used a gun instead of poison, and killed strangers instead of friends or family. One "analysis of 86 female serial killers from the United States found that the victims tended to be spouses, children or the elderly". Other studies indicate that since 1975, increasingly strangers are marginally the most preferred victim of female serial killers, or that only 26% of female serial killers kill for material gain only. Sources state that each killer will have her own proclivities, needs and triggers. A review of the published literature on female serial murder stated that "sexual or sadistic motives are believed to be extremely rare in female serial murderers, and psychopathic traits and histories of childhood abuse have been consistently reported in these women."
A study by Eric W. Hickey (2010) of 64 female serial killers in the United States indicated that sexual activity was one of several motives in 10% of the cases, enjoyment in 11% and control in 14% and that 51% of all U.S. female serial killers murdered at least one woman and 31% murdered at least one child. In other cases, women have been involved as an accomplice with a male serial killer as a part of a serial killing team. A 2015 study published in The Journal of Forensic Psychiatry & Psychology found that the most common motive for female serial killers was for financial gain and almost 40% of them had experienced some sort of mental illness.
A 2010 article by Perri and Lichtenwald addressed some of the misconceptions concerning female criminality. In the article, Perri and Lichtenwald analyze the current research regarding female psychopathy, including case studies of female psychopathic killers featuring Munchausen syndrome by proxy, cesarean section homicide, fraud detection homicide, female kill teams, and a female serial killer.
Juvenile serial killers are rare. There are three main categories that juvenile serial killers can fit into: primary, maturing, and secondary killers. There have been studies done to compare and contrast these three groups and to discover similarities and differences between them. Although these types of serial killers are less common, oftentimes adult serial killers may make their debut at an early age and it can be an opportunity for researchers to study what factors brought about the behavior. While juvenile serial killers are rare, the youngest felon on death row is a juvenile serial killer named Harvey Miguel Robinson who was 17 at the time of his crimes and 18 at the time of his arrest.
There is a myth that most serial killers are white males. However, according to the FBI, based on percentages of the U.S. population, white males are not more likely than other races to be serial killers. White males are actually greatly under-represented among serial killers in proportion to their overall numbers in the United States. According to a 2016 study, since the year 2000, African Americans accounted for roughly 60% of all serial killers in the United States.
Mission-oriented killers typically justify their acts as "ridding the world" of certain types of people perceived as undesirable, such as the homeless, ex-cons, homosexuals, drug users, prostitutes, or people of different ethnicity or religion; however, they are generally not psychotic. Some see themselves as attempting to change society, often to cure a societal ill.
This type of serial killer seeks thrills and derives pleasure and satisfaction from killing, seeing people as expendable means to this goal. Forensic psychologists have identified three subtypes of the hedonistic killer: "lust", "thrill", and "comfort".
Sex is the primary motive of lust killers, whether or not the victims are dead, and fantasy plays a large role in their killings. Their sexual gratification depends on the amount of torture and mutilation they perform on their victims. The sexual serial murderer has a psychological need to have absolute control, dominance, and power over their victims, and the infliction of torture, pain, and ultimately death is used in an attempt to fulfill their need. They usually use weapons that require close contact with the victims, such as knives or hands. As lust killers continue with their murders, the time between killings decreases or the required level of stimulation increases, sometimes both.
Dahmer once said, "Lust played a big part of it. Control and lust. Once it happened the first time, it just seemed like it had control of my life from there on in. The killing was just a means to an end. That was the least satisfactory part. I didn't enjoy doing that. That's why I tried to create living zombies with acid and the drill." He further elaborated on this, also saying, "I wanted to see if it was possible to make—again, it sounds really gross—uh, zombies, people that would not have a will of their own, but would follow my instructions without resistance. So after that, I started using the drilling technique." He experimented with cannibalism to "ensure his victims would always be a part of him".
The primary motive of a thrill killer is to induce pain or terror in their victims, which provides stimulation and excitement for the killer. They seek the adrenaline rush provided by hunting and killing victims. Thrill killers murder only for the kill; usually, the attack is not prolonged, and there is no sexual aspect. Usually, the victims are strangers, although the killer may have followed them for a period of time. Thrill killers can abstain from killing for long periods of time and become more successful at killing as they refine their murder methods. Many attempt to commit the perfect crime and believe they will not be caught.
Material gain and a comfortable lifestyle are the primary motives of comfort killers. Usually, the victims are family members and close acquaintances. After a murder, a comfort killer will usually wait for a period of time before killing again to allow any suspicions by family or authorities to subside. They often use poison, most notably arsenic, to kill their victims. Female serial killers are often comfort killers, although not all comfort killers are female.
The main objective for this type of serial killer is to gain and exert power over their victim. Such killers are sometimes abused as children, leaving them with feelings of powerlessness and inadequacy as adults. Many power- or control-motivated killers sexually abuse their victims, but they differ from hedonistic killers in that rape is not motivated by lust (as it would be with a lust murder) but as simply another form of dominating the victim. Ted Bundy is an example of a power/control-oriented serial killer. He traveled around the United States seeking women to control.
Killers who have a strong desire for fame or to be renowned for their actions desire media attention as a way of validating and spreading their crimes; fear is also a component here, as some serial killers enjoy causing fear. An example is Dennis Rader, who sought attention from the press during his murder spree.
Theories for why certain people commit serial murder have been advanced. Some theorists believe the reasons are biological, suggesting serial killers are born, not made, and that their violent behavior is a result of abnormal brain activity. Holmes believes that "until a reliable sample can be obtained and tested, there is no scientific statement that can be made concerning the exact role of biology as a determining factor of a serial killer personality."
"Social Process Theory" has also been suggested as an explanation for serial murder. Social process theory states that offenders may turn to crime due to peer pressure, family and friends. Criminal behavior is a process of interaction with social institutions, in which everyone has the potential for criminal behavior. A lack of family structure and identity could also be a cause leading to serial murder traits. A child used as a scapegoat will be deprived of their capacity to feel guilt. Displaced anger could result in animal torture, as identified in the Macdonald triad, and a further lack of basic identity.
The "military theory" has been proposed as an explanation for why serial murderers kill, as some serial murderers have served in the military or related fields. According to Castle and Hensley, 7% of the serial killers studied had military experience. This figure may be a proportional under-representation when compared to the number of military veterans in a nation's total population. For example, according to the United States census for the year 2000, military veterans comprised 12.7% of the U.S. population; in England, it was estimated in 2007 that military veterans comprised 9.1% of the population. Though by contrast, about 2.5% of the population of Canada in 2006 consisted of military veterans.
There are two theories that can be used to study the correlation between serial killing and military training: Applied learning theory states that serial killing can be learned. The military is training for higher kill rates from servicemen while training the soldiers to be desensitized to taking a human life. Social learning theory can be used when soldiers get praised and accommodated for killing. They learn or believe that they learn, that it is acceptable to kill because they were praised for it in the military. Serial killers want accreditation for the work that they have done.
In both military and serial killing, the offender or the soldier may become desensitized to killing as well as compartmentalized; the soldiers do not see enemy personnel as "human" and neither do serial killers see their victims as humans. The theories do not imply that military institutions make a deliberate effort to produce serial killers; to the contrary, all military personnel are trained to recognize when, where, and against whom it is appropriate to use deadly force, which starts with the basic Law of Land Warfare, taught during the initial training phase, and may include more stringent policies for military personnel in law enforcement or security.
According to the FBI, identifying one, or multiple, murders as being the work of a serial killer is the first challenge an investigation faces, especially if the victim(s) come from a marginalized or high-risk population and is normally linked through forensic or behavioral evidence. Should the cases cross multiple jurisdictions, the law enforcement system in the United States is fragmented and thus not configured to detect multiple similar murders across a large geographic area. Ted Bundy was particularly famous for such geographic exploitations. He used his knowledge about the lack of communication between multiple jurisdictions to avoid arrest and detection. The FBI suggests utilizing databases and increasing interdepartmental communication. Keppel suggests holding multi-jurisdictional conferences regularly to compare cases giving departments a greater chance to detect linked cases and overcome linkage blindness.
One collaboration, the Serial Homicide Expertise and Information Sharing Collaborative, was formed in 2010 and made serial murder data widely accessible after multiple experts combined their databases to aid in research and investigation. Another collaboration, the Radford/FGCU Serial Killer Database Project was proposed at the 2012 FDIAI Annual Conference. Utilizing Radford's Serial Killer Database as a starting point, the new collaboration, hosted by FGCU Justice Studies, has invited and is working in conjunction with other universities to maintain and expand the scope of the database to also include spree and mass murders. Utilizing over 170 data points, multiple-murderer methodology and victimology; researchers and Law Enforcement Agencies can build case studies and statistical profiles to further research the Who, What, Why and How of these types of crimes.
Leadership, or administration, should play a small or virtually non-existent role in the actual investigation past assigning knowledgeable or experienced homicide investigators to lead positions. The administration's role is not to run the investigation but to establish and reaffirm the primary goal of catching the serial killer, as well as provide support for the investigators. The FBI (2008) suggests completing Memorandums of Understanding to facilitate support and commitment of resources from different jurisdictions to an investigation. Egger takes this one step further and suggests completing mutual aid pacts, which are written agreements to provide support to each other in a time of need, with surrounding jurisdictions. Doing this in advance would save time and resources that could be used on the investigation.
The structural organization of an investigation is key to its success, as demonstrated by the investigation of Gary Ridgway, the Green River Killer. Once a serial murder case was established, a task force was created to track down and arrest the offender. Over the course of the investigation, for various reasons, the task force's organization was radically changed and reorganized multiple times – at one point including more than 50 full-time personnel, and at another, only a single investigator. Eventually, what led to the end of the investigation was a conference of 25 detectives organized to share ideas to solve the case.
The FBI handbook provides a description of how a task force should be organized but offers no additional options on how to structure the investigation. While it appears advantageous to have a full-time staff assigned to a serial murder investigation, it can become prohibitively expensive. For example, the Green River Task Force cost upwards of $2 million per year, and as was witnessed with the Green River Killer investigation, other strategies can prevail where a task force fails. A common strategy, already employed by many departments for other reasons, is the conference, in which departments get together and focus on a specific set of topics. With serial murders, the focus is typically on unsolved cases, with evidence thought to be related to the case at hand.
Similar to a conference is an information clearing-house in which a jurisdiction with a suspected serial murder case collects all of its evidence and actively seeks data that may be related from other jurisdictions. By collecting all of the related information into one place, they provide a central point in which it can be organized and easily accessed by other jurisdictions working toward the goal of arresting an offender and ending the murders. A task force provides for a flexible, organized, framework for jurisdictions depending on the needs of the investigation. Unfortunately due to the need to commit resources (manpower, money, equipment, etc.) for long periods of time it can be an unsustainable option.
In the case of the investigation of Aileen Wournos, the Marion County Sheriff coordinated multiple agencies without any written or formal agreement. While not a specific strategy for a serial murder investigation, this is certainly a best practice in so far as the agencies were able to work easily together toward a common goal. Finally, once a serial murder investigation has been identified, the use of an FBI Rapid Response Team can assist both experienced and inexperienced jurisdictions in setting up a task force. This is completed by organizing and delegating jobs, by compiling and analyzing clues, and by establishing communication between the parties involved.
During the course of a serial murder investigation, it may become necessary to call in additional resources; the FBI defines this as Resource Augmentation. Within the structure of a task force, the addition of a resource should be thought of as either long-term or short-term. If the task force's framework is expanded to include the new resource, then it should be permanent and not removed. For short-term needs, such as setting up roadblocks or canvassing a neighborhood, additional resources should be called in on a short-term basis. The decision of whether resources are needed short or long term should be left to the lead investigator and facilitated by the administration.
The confusion and counter productiveness created by changing the structure of a task force mid investigation is illustrated by the way the Green River Task Force's staffing and structure was changed multiple times throughout the investigation. This made an already complicated situation more difficult, resulting in the delay or loss of information, which allowed Ridgway to continue killing. The FBI model does not take into account that permanently expanding a task force, or investigative structure, may not be possible due to cost or personnel availability. Egger (1998) offers several alternative strategies including; using investigative consultants, or experienced staff to augment an investigative team. Not all departments have investigators experienced in serial murder and by temporarily bringing in consultants, they can educate a department to a level of competence then step out. This would reduce the initially established framework of the investigation team and save the department the cost of retaining the consultants until the conclusion of the investigation.
The FBI handbook (2008) and Keppel (1989) both stress communication as paramount. The difference is that the FBI handbook concentrates primarily on communication within a task force, while Keppel makes getting information out to and allowing information to be passed back from patrol officers a priority. The FBI handbook suggests having daily e-mail or in-person briefings for all staff involved in the investigation and providing periodic summary briefings to patrol officers and managers. Looking back on a majority of serial murderer arrests, most are exercised by patrol officers in the course of their everyday duties and unrelated to the ongoing serial murder investigation.
Keppel provides examples of Larry Eyler, who was arrested during a traffic stop for a parking violation, and Ted Bundy, who was arrested during a traffic stop for operating a stolen vehicle. In each case, it was uniformed officers, not directly involved in the investigation, who knew what to look for and took the direct action that stopped the killer. By providing up-to-date (as opposed to periodic) briefings and information to officers on the street the chances of catching a serial killer, or finding solid leads, are increased.
A serial murder investigation generates staggering amounts of data, all of which needs to be reviewed and analyzed. A standardized method of documenting and distributing information must be established and investigators must be allowed time to complete reports while investigating leads and at the end of a shift (FBI 2008). When the mechanism for data management is insufficient, leads are not only lost or buried but the investigation can be hindered and new information can become difficult to obtain or become corrupted.
During the Green River Killer investigation, reporters would often find and interview possible victims or witnesses ahead of investigators. The understaffed investigation was unable to keep up the information flow, which prevented them from promptly responding to leads. To make matters worse, investigators believed that the journalists, untrained in interviewing victims or witnesses of crimes, would corrupt the information and result in unreliable leads.
Notorious and infamous serial killers number in the thousands and a subculture revolves around their legacies. That subculture includes the collection, sale, and display of serial killer memorabilia, dubbed "murderabilia" by Andrew Kahan, one of the best-known opponents of collectors of serial killer remnants. Kahan is the director of the Mayor's Crime Victims Office in Houston. He is backed by the families of murder victims and "Son of Sam laws" existing in some states that prevent murderers from profiting from the publicity generated by their crimes.
Such memorabilia includes the paintings, writings, and poems of these killers. Recently, marketing has capitalized even more upon interest in serial killers with the rise of various merchandise such as trading cards, action figures, and books. Some serial killers attain celebrity status in the way they acquire fans and may have previous personal possessions auctioned off on websites like eBay. A few examples of this are Ed Gein's 150-pound stolen gravestone and Bobby Joe Long's sunglasses.
name = "Britannica" https://www.britannica.com/topic/serial-murder https://www.britannica.com/topic/serial-murder
An offender can be anyone:
Holmes & Holmes 1998, Serial murder is the killing of three or more people over a period of more than 30 days, with a significant cooling-off period between the murders The baseline number of three victims appears to be most common among those who are the academic authorities in the field. The time frame also appears to be an agreed-upon component of the definition.
Petherick 2005, p. 190 Three killings seem to be required in the most popular definition of serial killing since they are enough to provide a pattern within the killings without being overly restrictive.
Flowers 2012, p. 195 In general, most experts on serial murder require that a minimum of three murders be committed at different times and usually different places for a person to qualify as a serial killer.
Schechter 2012, p. 73 Most experts seem to agree, however, that to qualify as a serial killer, an individual has to slay a minimum of three unrelated victims.
"Definition of Serial Murder". Federal Bureau of Investigation. Retrieved August 20, 2024. (This source only requires two people)
- Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
An offender can be anyone:
Holmes & Holmes 1998, Serial murder is the killing of three or more people over a period of more than 30 days, with a significant cooling-off period between the murders The baseline number of three victims appears to be most common among those who are the academic authorities in the field. The time frame also appears to be an agreed-upon component of the definition.
Petherick 2005, p. 190 Three killings seem to be required in the most popular definition of serial killing since they are enough to provide a pattern within the killings without being overly restrictive.
Flowers 2012, p. 195 In general, most experts on serial murder require that a minimum of three murders be committed at different times and usually different places for a person to qualify as a serial killer.
Schechter 2012, p. 73 Most experts seem to agree, however, that to qualify as a serial killer, an individual has to slay a minimum of three unrelated victims.
"Definition of Serial Murder". Federal Bureau of Investigation. Retrieved August 20, 2024. (This source only requires two people)
- Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Burkhalter Chmelir 2003, p. 1, Morton 2005, pp. 4, 9 - Burkhalter Chmelir, Sandra (2003). "Serial Killers". In Robert Kastenbaum (ed.). Macmillan Encyclopedia of Death and Dying. Vol. 2. New York: Macmillan Reference USA/Thomson/Gale. p. 1. Archived from the original on May 3, 2009. https://web.archive.org/web/20090503121235/http://findarticles.com/p/articles/mi_gx5214/is_2003/ai_n19132282/?tag=content;col1
Geberth 1995, p. ? "The base population was 387 serial murderers, who killed (under various motivations), three or more persons over a period of time with cooling-off periods between the events. The author identified 232 male serial murderers who violated their victims sexually". - Geberth, Vernon J. (1995). "Psychopathic sexual sadists: The psychology and psychodynamics of serial killers". Law and Order. 43 (4): 82–86. Archived from the original on January 5, 2020. Retrieved July 25, 2013. http://www.practicalhomicide.com/articles/psexsad.htm
Morton 2005, pp. 4, 9. - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
"Serial Murder". Federal Bureau of Investigation. Retrieved August 20, 2024. https://www.fbi.gov/stats-services/publications/serial-murder
Ressler & Schachtman 1993, p. 29, Schechter 2003, p. 5 - Ressler, Robert K.; Schachtman, Thomas (1993). Whoever Fights Monsters: My Twenty Years Tracking Serial Killers for the FBI. New York: Macmillan/St. Martin's. ISBN 978-0-312-95044-6. https://archive.org/details/whoeverfightsmo00ress
Rule 2004, p. 225. - Rule, Ann (2004). Kiss Me, Kill Me: Ann Rule's Crime Files. Simon and Schuster. ISBN 9781416500032. https://books.google.com/books?id=Jtj8_7WxpUkC&pg=PA225
Gennat 1930, pp. 7, 27–32, 49–54, 79–82. - Gennat, Ernst (1930). "Die Düsseldorfer Sexualmorde". Kriminalistische Monatshefte.
Vronsky 2004 - Vronsky, Peter (2004). Serial Killers: The Method and Madness of Monsters. Penguin Group/Berkley. ISBN 978-0-425-19640-3.
"Review: The Meaning of Murder". Evening Star. Washington, D.C. May 30, 1967. p. 12, col. 4. /wiki/The_Washington_Star
Vronsky 2013. - Vronsky, Peter (2013). "Serial Killer Zombie Apocalypse and the Dawn of the Less Dead: An Introduction to Sexual Serial Murder Today", in Serial Killers: True Crime Anthology 2014. RJ Parker Publishing. ISBN 978-1494325893.
An offender can be anyone:
Holmes & Holmes 1998, Serial murder is the killing of three or more people over a period of more than 30 days, with a significant cooling-off period between the murders The baseline number of three victims appears to be most common among those who are the academic authorities in the field. The time frame also appears to be an agreed-upon component of the definition.
Petherick 2005, p. 190 Three killings seem to be required in the most popular definition of serial killing since they are enough to provide a pattern within the killings without being overly restrictive.
Flowers 2012, p. 195 In general, most experts on serial murder require that a minimum of three murders be committed at different times and usually different places for a person to qualify as a serial killer.
Schechter 2012, p. 73 Most experts seem to agree, however, that to qualify as a serial killer, an individual has to slay a minimum of three unrelated victims.
"Definition of Serial Murder". Federal Bureau of Investigation. Retrieved August 20, 2024. (This source only requires two people)
- Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Petherick 2005, p. 190. - Petherick, Wayne (2005). Serial Crime: Theoretical and Practical Issues in Behavioral Profiling. Elsevier. ISBN 9780080468549. Archived from the original on September 2, 2016. Retrieved June 15, 2016. https://books.google.com/books?id=U3-zunZ5eF4C&pg=PA190
Flowers 2012, p. 195. - Flowers, R. Barri (2012). The Dynamics of Murder: Kill or Be Killed. CRC Press. ISBN 9781439879740. Archived from the original on September 1, 2016. Retrieved June 15, 2016. https://books.google.com/books?id=MQnSBQAAQBAJ&pg=PA195
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Vronsky 2004 - Vronsky, Peter (2004). Serial Killers: The Method and Madness of Monsters. Penguin Group/Berkley. ISBN 978-0-425-19640-3.
Fuller, John R. & Hickey, Eric W.: Controversial Issues in Criminology; Allyn and Bacon, 1999. p. 36. https://books.google.com/books?id=EnxHAAAAMAAJ
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Yaksic, Enzo (November 1, 2018). "The folly of counting bodies: Using regression to transgress the state of serial murder classification systems". Aggression and Violent Behavior. 43: 26–32. doi:10.1016/j.avb.2018.08.007. ISSN 1359-1789. https://www.sciencedirect.com/science/article/pii/S1359178918300235
S. Waller (2011). Serial Killers – Philosophy for Everyone: Being and Killing. John Wiley & Sons. p. 56. ISBN 978-1-4443-4140-9. Archived from the original on January 20, 2021. Retrieved August 30, 2020. 978-1-4443-4140-9
Schlesinger 2000, p. 5. - Schlesinger, Louis B. (2000). Serial Offenders: Current Thought, Recent Findings. CRC Press. ISBN 978-0-8493-2236-5. https://archive.org/details/Serial_Offenders_Current_Thought_Recent_Findings
"Tanganyika: Murder by Lion". Time. November 4, 1957. Archived from the original on June 28, 2011. Retrieved April 13, 2014. https://web.archive.org/web/20110628222637/http://www.time.com/time/magazine/article/0%2C9171%2C867859%2C00.html
Qian 1993, p. 387. - Qian, Sima (1993). "Han Dynasty". Records of the Grand Historian: Han dynasty. Vol. I (Revised ed.). Columbia University Press. ISBN 978-0-231-08164-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=wDDLb8LjlNAC&pg=PP1
Al-Tabari. "Al-Tabari's History, vol. 36" (PDF). pp. 868–879 [123]. Archived (PDF) from the original on October 9, 2022. https://archive.org/download/tabarivolume36/Tabari_Volume_36.pdf
Newton 2006, p. 95. - Newton, Michael (2006). The Encyclopedia of Serial Killers. Infobase Publishing. ISBN 9780816069873. Archived from the original on June 1, 2020. Retrieved February 27, 2016. https://books.google.com/books?id=DwNVbOcTncwC
Dirk C. Gibson (2014). Serial Killers Around the World: The Global Dimensions of Serial Murder. Bentham Science Publishers. pp. 3–5. ISBN 978-1-60805-842-6. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-60805-842-6
Salfati, Gabrielle; et al. (2015). "South African Serial Homicide: Offender and Victim Demographics and Crime Scene Actions" (PDF). Journal of Investigative Psychology and Offender Profiling. 12: 18–43. doi:10.1002/jip.1425. ISSN 1544-4759. Archived (PDF) from the original on August 15, 2019. Retrieved August 15, 2019. http://forensic-psychologist.co.za/wp-content/uploads/2017/08/South-African-Serial-Homicide-Offender-and-Victim-Demographics-and-Crime-Scene-Actions-2015.pdf
Vronsky 2004, pp. 45–48. - Vronsky, Peter (2004). Serial Killers: The Method and Madness of Monsters. Penguin Group/Berkley. ISBN 978-0-425-19640-3.
Vronsky 2004, p. 47. - Vronsky, Peter (2004). Serial Killers: The Method and Madness of Monsters. Penguin Group/Berkley. ISBN 978-0-425-19640-3.
Vronsky 2007, p. 78. - Vronsky, Peter (2007). Female Serial Killers: How and Why Women Become Monsters. New York: Berkley Publishing Group. ISBN 978-0-425-21390-2. Archived from the original on May 14, 2019. Retrieved February 27, 2016. https://books.google.com/books?id=lff8T6YnG10C
"2 of the Earliest Serial Killers in History". aezoutbailbonds.com. April 27, 2022. Archived from the original on September 24, 2023. Retrieved September 11, 2023. https://aezoutbailbonds.com/2-of-the-earliest-serial-killers-in-history/
Rubinstein 2004, pp. 82–83. - Rubinstein, W. D. (2004). Genocide: A History. Pearson Longman. ISBN 9780582506015. Archived from the original on September 10, 2015. Retrieved February 27, 2016. https://books.google.com/books?id=nMMAk4VwLLwC
Newton 2006, p. 117. - Newton, Michael (2006). The Encyclopedia of Serial Killers. Infobase Publishing. ISBN 9780816069873. Archived from the original on June 1, 2020. Retrieved February 27, 2016. https://books.google.com/books?id=DwNVbOcTncwC
Norder, Vanderlinden & Begg 2004. - Norder, Dan; Vanderlinden, Wolf; Begg, Paul (2004). Ripper Notes: Madmen, Myths and Magic. Inklings Press. ISBN 9780975912911. https://books.google.com/books?id=w2YjJKWZvz4C&pg=PA18
"Jack The Ripper: The First Serial Killer". Archived from the original on February 2, 2015. Retrieved September 1, 2020. https://atlanticproductions.tv/productions/jack-the-ripper-the-first-serial-killer/
"Jack the Ripper | Identity, Facts, Victims, and Suspects | Britannica". www.britannica.com. Archived from the original on January 25, 2023. Retrieved January 24, 2023. https://www.britannica.com/biography/Jack-the-Ripper
Canter 1994, pp. 12–13. - Canter, David (1994). Criminal Shadows: Inside the Mind of the Serial Killer. HarperCollins. ISBN 9780002552158. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=nJkbAQAAMAAJ&q=0002552159
Canter 1994, pp. 5–6. - Canter, David (1994). Criminal Shadows: Inside the Mind of the Serial Killer. HarperCollins. ISBN 9780002552158. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=nJkbAQAAMAAJ&q=0002552159
Davenport-Hines 2004, Woods & Baddeley 2009, pp. 20, 52 - Davenport-Hines, Richard (2004). "Jack the Ripper (fl. 1888), serial killer". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/38744. Archived from the original on July 8, 2019. Retrieved October 2, 2018. http://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-38744
Davenport-Hines 2004, Woods & Baddeley 2009, pp. 20, 52 - Davenport-Hines, Richard (2004). "Jack the Ripper (fl. 1888), serial killer". Oxford Dictionary of National Biography (online ed.). Oxford University Press. doi:10.1093/ref:odnb/38744. Archived from the original on July 8, 2019. Retrieved October 2, 2018. http://www.oxforddnb.com/view/10.1093/ref:odnb/9780198614128.001.0001/odnb-9780198614128-e-38744
Bardsley, Marilyn. "Jack the Ripper – the most famous serial killer of all time". truTV. Archived from the original on June 1, 2009. Retrieved August 3, 2009. https://web.archive.org/web/20090601180208/http://www.trutv.com/library/crime/serial_killers/notorious/ripper/index_1.html
Ramsland, Katherine. "The Werewolf Syndrome: Compulsive Bestial Slaughterers. Vacher the Ripper". truTV. Archived from the original on July 16, 2009. Retrieved August 3, 2009. https://web.archive.org/web/20090716023114/http://www.trutv.com/library/crime/criminal_mind/psychology/werewolf_killers/14.html
"French 'Ripper' Guillotined – Joseph Vacher, Who Murdered More Than a Score of Persons, Executed at Bourg-en-Bresse". The New York Times. January 1, 1899. p. 7. Archived from the original on June 28, 2011. Retrieved August 3, 2009. https://query.nytimes.com/gst/abstract.html?res=9C06E5DF1738E733A25752C0A9679C94689ED7CF
Urie, Chris. "9 serial killers from around the world you may not have heard of". Insider. Archived from the original on January 7, 2024. Retrieved January 24, 2023. https://www.insider.com/serial-killers-around-the-world-2018-9
Ehrlich, Brenna (February 10, 2021). "Why Were There So Many Serial Killers Between 1970 and 2000 – and Where Did They Go?". Rolling Stone. Archived from the original on April 29, 2021. Retrieved May 13, 2021. https://www.rollingstone.com/culture/culture-features/serial-killers-1970s-2000s-murders-1121705/
Martin, G. (2018). Crime, Media and Culture. Taylor & Francis. p. 2-PT71. ISBN 978-1-317-36897-7. Retrieved May 21, 2024. 978-1-317-36897-7
Yaksic, Enzo; Allely, Clare; De Silva, Raneesha; Smith-Inglis, Melissa; Konikoff, Daniel; Ryan, Kori; Gordon, Dan; Denisov, Egor; Keatley, David A. (January 2019). Chan, Heng Choon (Oliver) (ed.). "Detecting a decline in serial homicide: Have we banished the devil from the details?". Cogent Social Sciences. 5 (1). doi:10.1080/23311886.2019.1678450. ISSN 2331-1886. https://www.tandfonline.com/doi/full/10.1080/23311886.2019.1678450
Taylor, David (September 15, 2018). "Are American serial killers a dying breed?". The Guardian. Archived from the original on April 26, 2021. Retrieved May 13, 2021. https://www.theguardian.com/us-news/2018/sep/15/are-american-serial-killers-a-dying-breed
Levitt, Stephen (2004). "Understanding Why Crime Fell in the 1990s: Four Factors that Explain the Decline and Six that Do Not" (PDF). Journal of Economic Perspectives. 18 (1): 163–190. doi:10.1257/089533004773563485. Archived (PDF) from the original on November 24, 2005. /wiki/Steven_Levitt
J. Sampson, Robert; S. Winter, Alix (May 2018). "Poisoned Development: Assessing Childhood Lead Exposure as a Cauase of Crime in a Birth Cohort Followed Through Adolescence: Lead Poisoning and Crime". Criminology. 56 (2): 269–301. doi:10.1111/1745-9125.12171. https://doi.org/10.1111%2F1745-9125.12171
Reyes, Jessica Wolpaw (October 17, 2007). "Environmental Policy as Social Policy? The Impact of Childhood Lead Exposure on Crime". The B.E. Journal of Economic Analysis & Policy. 7 (1). doi:10.2202/1935-1682.1796. ISSN 1935-1682. Archived from the original on November 2, 2022. Retrieved November 2, 2022. https://www.degruyter.com/document/doi/10.2202/1935-1682.1796/html
Morton 2005, Skeem et al., pp. 95–162 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Bartol & Bartol 2004, p. 145. - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Cleckley, Hervey M. (1951). "The Mask of Sanity". Postgraduate Medicine. 9 (3): 193–197. doi:10.1080/00325481.1951.11694097. ISSN 0032-5481. PMID 14807904. http://www.tandfonline.com/doi/full/10.1080/00325481.1951.11694097
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Silva, Leong & Ferrari 2004, p. 794. - Silva, J. Arturo; Leong, Gregory B.; Ferrari, Michelle M. (2004). "A neuropsychiatric developmental model of serial homicidal behavior". Behavioral Sciences & the Law. 22 (6): 787–799. doi:10.1002/bsl.620. PMID 15568202. https://doi.org/10.1002%2Fbsl.620
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Singer & Hensley 2004, pp. 48, 461–476. - Singer, S.D; Hensley, C (2004). "Learning theory to childhood and adolescent fire-setting: Can it lead to serial murder". International Journal of Offender Therapy and Comparative Criminology. 48 (4): 461–476. doi:10.1177/0306624X04265087. PMID 15245657. S2CID 5991918. https://doi.org/10.1177%2F0306624X04265087
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Mount 2007, pp. 131–133. - Mount, George (2007). "Predicting Dangerousness". Journal of Police Crisis Negotiations. 7: 131–133. doi:10.1300/j173v07n01_11. S2CID 216088854. https://doi.org/10.1300%2Fj173v07n01_11
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Holloway, Lynette. Of Course There Are Black Serial Killers Archived October 13, 2013, at the Wayback Machine. The Root. http://www.theroot.com/views/course-there-are-black-serial-killers
"Serial Killer IQ". Archived from the original on March 4, 2016. Retrieved May 13, 2009. http://maamodt.asp.radford.edu/Serial%20Killer%20Information%20Center/Serial%20Killer%20IQ.htm
"Serial Killers: Insane or Super Intelligent?". www.psychologytoday.com. Archived from the original on January 7, 2024. Retrieved February 11, 2023. https://www.psychologytoday.com/us/blog/captivating-crimes/202006/serial-killers-insane-or-super-intelligent
"UK | Harold Shipman: The killer doctor". BBC News. January 13, 2004. Archived from the original on December 1, 2019. Retrieved July 29, 2010. http://news.bbc.co.uk/2/hi/uk_news/3391897.stm
"CrimeLibrary.com/Serial Killers/Sexual Predators/Dennis Nilsen – Growing Up Alone – Crime Library on". Trutv.com. November 23, 1945. Archived from the original on January 6, 2010. Retrieved July 29, 2010. https://web.archive.org/web/20100106081640/http://www.trutv.com/library/crime/serial_killers/predators/nilsen/alone_4.html
Testorides, Konstantin (June 24, 2008). "'Serial murder' journalist commits suicide". The Independent. London. Archived from the original on May 14, 2019. Retrieved July 29, 2010. https://www.independent.co.uk/news/world/europe/serial-murder-journalist-commits-suicide-852848.html
Mellor 2012. - Mellor, Lee (2012). Cold North Killers: Canadian Serial Murder. Dundurn. ISBN 9781459701243. Archived from the original on January 20, 2021. Retrieved November 21, 2020. https://books.google.com/books?id=owE8L_8s21EC&q=9781459701243
Rod Plotnik; Haig Kouyoumdjian (2010). Introduction to Psychology. Cengage Learning. p. 509. ISBN 978-1-111-79100-1. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-111-79100-1
Holmes & Holmes 2000, p. 107. - Holmes, Ronald M; Holmes, Stephen T (2000). Mass murder in the United States. Prentice Hall. ISBN 978-0-13-934308-7.
Tithecott 1997, p. 38. - Tithecott, R (1997). Of Men and Monsters: Jeffrey Dahmer and the Construction of the Serial Killer. Madison, Wisconsin: The University of Wisconsin Press. ISBN 978-0-299-15680-0. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=9E9navv807cC&pg=PP1
Hale 1993, p. 41. - Hale, Robert L. (January 9, 1993). "The Application of Learning Theory to Serial Murder or 'You Too Can Learn to be a Serial Killer'". American Journal of Criminal Justice. 17 (2): 37–45. doi:10.1007/BF02885952. S2CID 144186286. Archived from the original on October 3, 2018. Retrieved October 1, 2018. https://www.researchgate.net/publication/225783432
Hasselt 1999, p. 162. - Hasselt, V. B. Van (1999). Handbook of psychological approaches with violent offenders: Contemporary strategies and issues. Kluwer Academic / Plenum Publishers. ISBN 9780306458453. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=K4v-xqq4SmsC&pg=PP1
Wilson & Seaman 1992. - Wilson, Colin; Seaman, Donald (1992). The Serial Killers: A Study in the Psychology of Violence. True Crime. ISBN 9780863696152. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=GeR9QgAACAAJ
Hasselt 1999, p. 162. - Hasselt, V. B. Van (1999). Handbook of psychological approaches with violent offenders: Contemporary strategies and issues. Kluwer Academic / Plenum Publishers. ISBN 9780306458453. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=K4v-xqq4SmsC&pg=PP1
Hickey 2010, p. 107. - Hickey, Eric W. (2010). Serial murderers and their victims. Wadsworth, Cengage Learning.
Maccoby 1992, pp. 1006–1017. - Maccoby, E. E (1992). "The role of parents in the socialization of children: An historical overview". Developmental Psychology. 28 (6): 1006–1017. doi:10.1037/0012-1649.28.6.1006. S2CID 7266774. https://doi.org/10.1037%2F0012-1649.28.6.1006
Berit Brogaard, D.M.Sci., Ph.D (2018). "Do All Serial Killers Have a Genetic Predisposition to Kill? – Exploring a Complex Question". Psychology Today. Archived from the original on September 7, 2020. Retrieved September 1, 2020.{{cite web}}: CS1 maint: multiple names: authors list (link) https://www.psychologytoday.com/blog/the-superhuman-mind/201803/do-all-serial-killers-have-genetic-predisposition-kill
Ramsland, Katherine. "Shame and the Serial Killer: Humiliation's influence on criminal behavior needs more attention". Psychology Today. Archived from the original on January 10, 2022. Retrieved September 13, 2020. https://www.psychologytoday.com/us/blog/shadow-boxing/201909/shame-and-the-serial-killer
Engel, Eric (September 1972). "The making of an XYY". Am J Ment Defic. 77 (2): 123–7. PMID 5081078. /wiki/PMID_(identifier)
Robinson, Arthur; Lubs, Herbert A.; Bergsma, Daniel, eds. (1979). Sex chromosome aneuploidy: prospective studies on children. Birth defects original article series 15 (1). New York: Alan R. Liss. ISBN 978-0-8451-1024-9.
Stewart, Donald A., ed. (1982). Children with sex chromosome aneuploidy: follow-up studies. Birth defects original article series 18 (4). New York: Alan R. Liss. ISBN 978-0-8451-1052-2.
Ratcliffe, Shirley G.; Paul, Natalie, eds. (1986). Prospective studies on children with sex chromosome aneuploidy. Birth defects original article series 22 (3). New York: Alan R. Liss. ISBN 978-0-8451-1062-1.
Evans, Jane A.; Hamerton, John L.; Robinson, Arthur, eds. (1991). Children and young adults with sex chromosome aneuploidy: follow-up, clinical and molecular studies. Birth defects original article series 26 (4). New York: Wiley-Liss. ISBN 978-0-471-56846-9.
978-0-8451-1024-9978-0-8451-1052-2978-0-8451-1062-1978-0-471-56846-9
Giannangelo 1996, p. 33. - Giannangelo, Stephen J. (1996). The Psychopathology of Serial Murder: A Theory of Violence. Greenwood Publishing Group. ISBN 9780275954345. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=rPLpWHyrM-MC&pg=PA33
Tithecott 1997, p. 38. - Tithecott, R (1997). Of Men and Monsters: Jeffrey Dahmer and the Construction of the Serial Killer. Madison, Wisconsin: The University of Wisconsin Press. ISBN 978-0-299-15680-0. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=9E9navv807cC&pg=PP1
Silva, Leong & Ferrari 2004, p. 790, Tithecott 1997, p. 43 - Silva, J. Arturo; Leong, Gregory B.; Ferrari, Michelle M. (2004). "A neuropsychiatric developmental model of serial homicidal behavior". Behavioral Sciences & the Law. 22 (6): 787–799. doi:10.1002/bsl.620. PMID 15568202. https://doi.org/10.1002%2Fbsl.620
Silva, Leong & Ferrari 2004, p. 790, Tithecott 1997, p. 43 - Silva, J. Arturo; Leong, Gregory B.; Ferrari, Michelle M. (2004). "A neuropsychiatric developmental model of serial homicidal behavior". Behavioral Sciences & the Law. 22 (6): 787–799. doi:10.1002/bsl.620. PMID 15568202. https://doi.org/10.1002%2Fbsl.620
Hasselt 1999, p. 162. - Hasselt, V. B. Van (1999). Handbook of psychological approaches with violent offenders: Contemporary strategies and issues. Kluwer Academic / Plenum Publishers. ISBN 9780306458453. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=K4v-xqq4SmsC&pg=PP1
Cotter, P. (2010). "The path to extreme violence: Nazism and serial killers". Frontiers in Behavioral Neuroscience. 3 61: 1–5. doi:10.3389/neuro.08.061.2009. PMC 2813721. PMID 20126638. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2813721
Vronsky 2004, pp. 99–100. - Vronsky, Peter (2004). Serial Killers: The Method and Madness of Monsters. Penguin Group/Berkley. ISBN 978-0-425-19640-3.
Joshua A. Perper; Stephen J. Cina (2010). When Doctors Kill: Who, Why, and How. Springer Science & Business Media. p. 51. ISBN 978-1-4419-1371-5. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-4419-1371-5
Dennis L. Peck; Norman Dolch; Norman Allan Dolch (2001). Extraordinary Behavior: A Case Study Approach to Understanding Social Problems. Greenwood Publishing Group. p. 253. ISBN 978-0-275-97057-4. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-0-275-97057-4
Ressler & Schachtman 1993, p. 113. - Ressler, Robert K.; Schachtman, Thomas (1993). Whoever Fights Monsters: My Twenty Years Tracking Serial Killers for the FBI. New York: Macmillan/St. Martin's. ISBN 978-0-312-95044-6. https://archive.org/details/whoeverfightsmo00ress
Ressler & Schachtman 1993, p. 113. - Ressler, Robert K.; Schachtman, Thomas (1993). Whoever Fights Monsters: My Twenty Years Tracking Serial Killers for the FBI. New York: Macmillan/St. Martin's. ISBN 978-0-312-95044-6. https://archive.org/details/whoeverfightsmo00ress
"Serial Killer Statistics". Retrieved March 1, 2021. https://www.researchgate.net/publication/342501023
"Serial Killers". Archived from the original on March 9, 2009. Retrieved May 21, 2009. https://web.archive.org/web/20090309132810/http://www.enotes.com/forensic-science/serial-killers
"Serial Killer Statistics". Retrieved March 1, 2021. https://www.researchgate.net/publication/342501023
Hickey 2010, p. 142 - Hickey, Eric W. (2010). Serial murderers and their victims. Wadsworth, Cengage Learning.
Wires, Linda (2015). "Angels of Death". New Scientist. 225 (3007): 40–43. Bibcode:2015NewSc.225...40W. doi:10.1016/S0262-4079(15)60268-8. Archived from the original on December 18, 2008. Retrieved December 30, 2008. https://web.archive.org/web/20081218133027/http://www.trutv.com/library/crime/notorious_murders/angels/index.html
Holmes & Holmes 1998, p. 204. - Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Ramsland, Katherine (March 22, 2007). "When Women Kill Together". The Forensic Examiner. American College of Forensic Examiners Institute. Archived from the original on August 29, 2010. Retrieved August 2, 2009. https://web.archive.org/web/20100829110653/http://findarticles.com/p/articles/mi_go1613/is_1_16/ai_n29335603/
Ramsland, Katherine (March 22, 2007). "When Women Kill Together". The Forensic Examiner. American College of Forensic Examiners Institute. Archived from the original on August 29, 2010. Retrieved August 2, 2009. https://web.archive.org/web/20100829110653/http://findarticles.com/p/articles/mi_go1613/is_1_16/ai_n29335603/
"Genene Jones Biography". Archived from the original on June 3, 2012. https://web.archive.org/web/20120603170851/http://www.biography.com/people/genene-jones-235417
"Genene Jones Biography". Archived from the original on June 3, 2012. https://web.archive.org/web/20120603170851/http://www.biography.com/people/genene-jones-235417
"Genene Jones Biography". Archived from the original on June 3, 2012. https://web.archive.org/web/20120603170851/http://www.biography.com/people/genene-jones-235417
"Murder in the ICU: Inside the Twisted Case of a Hospital Nurse Who Turned Out To Be a Serial Killer". Peoplemag. Archived from the original on April 12, 2022. Retrieved April 12, 2022. https://people.com/crime/texas-hospital-nurse-serial-killer-murdered-patients-with-ivs/
Kelleher & Kelleher 1998, p. 12, Wilson & Hilton 1998, pp. 495–498, Frei et al. 2006, pp. 167–176 - Kelleher, Michael D.; Kelleher, C.L. (1998). Murder Most Rare: The Female Serial Killer. Westport, Connecticut: Praeger. ISBN 978-0-275-96003-2. Archived from the original on April 20, 2010. Retrieved September 11, 2017. https://www.questia.com/PM.qst?a=o&d=14217482
Hickey 2010, pp. 187, 257, 266, Vronsky 2007, p. 9, Farrell, Keppel & Titterington 2011, pp. 228–252 - Hickey, Eric W. (2010). Serial murderers and their victims. Wadsworth, Cengage Learning.
Farrell, Keppel & Titterington 2011, pp. 228–252 - Farrell, Amanda L.; Keppel, Robert D.; Titterington, Victoria B. (August 2011). "Lethal Ladies: Revisiting What We Know About Female Serial Murderers". Homicide Studies. 15 (3): 228–252. doi:10.1177/1088767911415938. S2CID 144327931. https://doi.org/10.1177%2F1088767911415938
Newton 2006 - Newton, Michael (2006). The Encyclopedia of Serial Killers. Infobase Publishing. ISBN 9780816069873. Archived from the original on June 1, 2020. Retrieved February 27, 2016. https://books.google.com/books?id=DwNVbOcTncwC
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Educated attempt to provide specific information about a certain type of suspect. Department of Psychology, Concordia University. 2008. Archived from the original (PPT) on April 26, 2012. Retrieved July 1, 2010. https://web.archive.org/web/20120426081443/http://www-psychology.concordia.ca/fac/Laurence/forensic/ProfileAnalysis1.ppt
Kelleher & Kelleher 1998, p. 12, Wilson & Hilton 1998, pp. 495–498, Frei et al. 2006, pp. 167–176 - Kelleher, Michael D.; Kelleher, C.L. (1998). Murder Most Rare: The Female Serial Killer. Westport, Connecticut: Praeger. ISBN 978-0-275-96003-2. Archived from the original on April 20, 2010. Retrieved September 11, 2017. https://www.questia.com/PM.qst?a=o&d=14217482
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Wilson & Hilton 1998, pp. 495–498, Frei et al. 2006, pp. 167–176, Holmes & Holmes 1998, p. 171, Newton 2006 - Wilson, W.; Hilton, T. (1998). "Modus operandi of female serial killers". Psychological Reports. 82 (2): 495–498. doi:10.2466/PR0.82.2.495-498. PMID 9621726. https://doi.org/10.2466%2FPR0.82.2.495-498
Educated attempt to provide specific information about a certain type of suspect. Department of Psychology, Concordia University. 2008. Archived from the original (PPT) on April 26, 2012. Retrieved July 1, 2010. https://web.archive.org/web/20120426081443/http://www-psychology.concordia.ca/fac/Laurence/forensic/ProfileAnalysis1.ppt
Vronsky 2007, pp. 1, 42–43, Schechter 2003, p. 312 - Vronsky, Peter (2007). Female Serial Killers: How and Why Women Become Monsters. New York: Berkley Publishing Group. ISBN 978-0-425-21390-2. Archived from the original on May 14, 2019. Retrieved February 27, 2016. https://books.google.com/books?id=lff8T6YnG10C
Schechter 2003, p. 31, Fox & Levin 2005, p. 117 - Schechter, Harold (2003). The Serial Killer Files: The Who, What, Where, How, and Why of the World's Most Terrifying Murderers. Ballantine Books. ISBN 978-0-345-47200-7. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=5qroGXAa-wIC&pg=PP1
Schmid 2005, p. 231, Arrigo & Griffin 2004, pp. 375–393 - Schmid, David (2005). Natural Born Celebrities: Serial Killers in American Culture. University of Chicago Press. ISBN 978-0-226-73867-3. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=a_GwiSGfZFoC&pg=PP1
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Vronsky 2007, p. 41. - Vronsky, Peter (2007). Female Serial Killers: How and Why Women Become Monsters. New York: Berkley Publishing Group. ISBN 978-0-425-21390-2. Archived from the original on May 14, 2019. Retrieved February 27, 2016. https://books.google.com/books?id=lff8T6YnG10C
Hickey 2010, p. 267. - Hickey, Eric W. (2010). Serial murderers and their victims. Wadsworth, Cengage Learning.
Wilson & Hilton 1998, pp. 495–498 - Wilson, W.; Hilton, T. (1998). "Modus operandi of female serial killers". Psychological Reports. 82 (2): 495–498. doi:10.2466/PR0.82.2.495-498. PMID 9621726. https://doi.org/10.2466%2FPR0.82.2.495-498
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Hickey 2010, p. 265. - Hickey, Eric W. (2010). Serial murderers and their victims. Wadsworth, Cengage Learning.
Wilson & Hilton 1998, pp. 495–498 - Wilson, W.; Hilton, T. (1998). "Modus operandi of female serial killers". Psychological Reports. 82 (2): 495–498. doi:10.2466/PR0.82.2.495-498. PMID 9621726. https://doi.org/10.2466%2FPR0.82.2.495-498
Frei et al. 2006, pp. 167–176 - Frei, A.; Völlm, B.; Graf, M.; Dittmann, V. (2006). "Female serial killing: Review and case report". Criminal Behaviour and Mental Health. 16 (33): 167–176. doi:10.1002/cbm.615. PMID 16838388. https://doi.org/10.1002%2Fcbm.615
Harrison et al., pp. 383–406. - Harrison, Marissa A.; Murphy, Erin A.; Ho, Lavina Y.; Bowers, Thomas G.; Flaherty, Claire V. (2015). "Female serial killers in the United States: means, motives, and makings". The Journal of Forensic Psychiatry & Psychology. 26 (3): 383–406. doi:10.1080/14789949.2015.1007516. S2CID 145149823. https://doi.org/10.1080%2F14789949.2015.1007516
Vronsky 2007. - Vronsky, Peter (2007). Female Serial Killers: How and Why Women Become Monsters. New York: Berkley Publishing Group. ISBN 978-0-425-21390-2. Archived from the original on May 14, 2019. Retrieved February 27, 2016. https://books.google.com/books?id=lff8T6YnG10C
Eric W. Hickey, (2010). https://archive.today/20130215231752/http://www.erichickey.com/
Yardley & Wilson 2015, pp. 1–26. - Yardley, Elizabeth; Wilson, David (2015). Female Serial Killers in Social Context: Criminological Institutionalism and the Case of Mary Ann Cotton. Policy Press. ISBN 9781447327639. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=wCu4nQAACAAJ
Vronsky 2007, p. 73. - Vronsky, Peter (2007). Female Serial Killers: How and Why Women Become Monsters. New York: Berkley Publishing Group. ISBN 978-0-425-21390-2. Archived from the original on May 14, 2019. Retrieved February 27, 2016. https://books.google.com/books?id=lff8T6YnG10C
Perri & Lichtenwald 2010, pp. 50–67 - Perri, Frank S.; Lichtenwald, Terrance G. (2010). "The Last Frontier: Myths & The Female Psychopathic Killer" (PDF). Forensic Examiner. 19 (2). Archived (PDF) from the original on July 7, 2011. Retrieved June 12, 2010. http://www.all-about-forensic-psychology.com/support-files/female-psychopathic-killers.pdf
Perri & Lichtenwald 2010, pp. 50–67 - Perri, Frank S.; Lichtenwald, Terrance G. (2010). "The Last Frontier: Myths & The Female Psychopathic Killer" (PDF). Forensic Examiner. 19 (2). Archived (PDF) from the original on July 7, 2011. Retrieved June 12, 2010. http://www.all-about-forensic-psychology.com/support-files/female-psychopathic-killers.pdf
Kirby 2009. - Kirby, Ashley M. (2009). Juvenile Serial Killers: Descriptive Characteristics and Profiles. Alliant International University, California School of Forensic Psychology, Fresno. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=Kpn1ZwEACAAJ
"Youngest Serial Killer on Death Row". Psychology Today. Archived from the original on January 20, 2021. Retrieved March 2, 2018. https://www.psychologytoday.com/blog/shadow-boxing/201207/youngest-serial-killer-death-row
"Harvey Robinson". National Organization of Victims of Juvenile Murderers. January 21, 2021. Archived from the original on May 17, 2022. Retrieved March 27, 2022. https://teenkillers.org/juvenile-lifers/offenders-cases-state/pennsylvania-offenders/harvey-robinson/
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Morton 2005 - Morton, RJ (2005). "Serial murder multi-disciplinary perspectives for investigators" (PDF). Federal Bureau of Investigation. Archived from the original on June 15, 2016. Retrieved July 16, 2011. https://www.fbi.gov/stats-services/publications/serial-murder/serial-murder-july-2008-pdf
Walsh, A.; Jorgensen, C. (2019). Criminology: The Essentials. Sage Publications. p. 291. ISBN 978-1-5443-7539-7. Retrieved May 21, 2024. "The reality is that white males are very much underrepresented among serial killers in proportion to their numbers in the population. Hickey (2006) claims that about 44% of serial killers operating from 1995 to 2004 have been African American, which is about 3.4 times greater than expected by the proportion of African Americans in the population. More recently, the Radford University's Serial Killer Information Center (Aamodt, 2016) found that since 2000 African Americans have been 59.8% of serial killers in the United States, whites 30.8%, Hispanics 6.7%, and Asian Americans 0.1%." 978-1-5443-7539-7
Walsh, A.; Jorgensen, C. (2019). Criminology: The Essentials. Sage Publications. p. 291. ISBN 978-1-5443-7539-7. Retrieved May 21, 2024. "The reality is that white males are very much underrepresented among serial killers in proportion to their numbers in the population. Hickey (2006) claims that about 44% of serial killers operating from 1995 to 2004 have been African American, which is about 3.4 times greater than expected by the proportion of African Americans in the population. More recently, the Radford University's Serial Killer Information Center (Aamodt, 2016) found that since 2000 African Americans have been 59.8% of serial killers in the United States, whites 30.8%, Hispanics 6.7%, and Asian Americans 0.1%." 978-1-5443-7539-7
Walsh, Anthony (November 28, 2011). "African Americans and Serial Killing in the Media: The Myth and the Reality". Homicide Studies. Retrieved May 21, 2024. "There were many expressions of shock and surprise voiced in the media in 2002 when the “D.C. Sniper” turned out to be two Black males. Two of the stereotypes surrounding serial killers are that they are almost always White males and that African American males are barely represented in their ranks. In a sample of 413 serial killers operating in the United States from 1945 to mid-2004, it was found that 90 were African American. Relative to the African American proportion of the population across that time period, African Americans were overrepresented in the ranks of serial killers by a factor of about 2...The myth that serial killers are rarely African-Americans has had two detrimental effects. First, Whites tend to argue that Blacks are not sufficiently psychologically complex or intelligent to commit a series of murders without being caught. Second, police tend to neglect the protection of potential victims of serial killers in African-American communities. 1 table, 4 notes, and 64 references" https://scholarworks.boisestate.edu/crimjust_facpubs/113/
Walsh 2005, pp. 271–291. - Walsh, Anthony (November 2005). "African Americans and Serial Killing in the Media". Homicide Studies. 9 (4): 271–291. doi:10.1177/1088767905280080. ISSN 1088-7679. S2CID 143399844. Archived from the original on May 14, 2019. Retrieved October 2, 2018. https://scholarworks.boisestate.edu/crimjust_facpubs/113/
Holmes & Holmes 1998, pp. 43–44, Bartol & Bartol 2004, p. 284 - Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Scott Bonn (2014). Why We Love Serial Killers: The Curious Appeal of the World's Most Savage Murderers. Skyhorse. pp. 108–. ISBN 978-1-63220-189-8. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-63220-189-8
Holmes & Holmes 1998, p. 62. - Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Bartol & Bartol 2004, p. 145. - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Ressler & Schachtman 1993, p. 146. - Ressler, Robert K.; Schachtman, Thomas (1993). Whoever Fights Monsters: My Twenty Years Tracking Serial Killers for the FBI. New York: Macmillan/St. Martin's. ISBN 978-0-312-95044-6. https://archive.org/details/whoeverfightsmo00ress
Schechter 2003, p. 291. - Schechter, Harold (2003). The Serial Killer Files: The Who, What, Where, How, and Why of the World's Most Terrifying Murderers. Ballantine Books. ISBN 978-0-345-47200-7. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=5qroGXAa-wIC&pg=PP1
Abrahamsen, David (July 1, 1979). "The Demons of 'Son of Sam'". St. Louis Post-Dispatch. Vol. 101, no. 168. pp. 2G, 5G. Archived from the original on February 2, 2018. Retrieved February 1, 2018. https://www.newspapers.com/image/139894111
Holmes & Holmes 1998, p. 43. - Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
Holmes & Holmes 2002, p. 112. - Holmes, Ronald M.; Holmes, Stephen T. (2002). Profiling Violent Crimes: An Investigative Tool. Sage. ISBN 978-0-7619-2594-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=a2uYI0C_AXkC&pg=PP1
Scott, Jason (February 18, 2020). "'The worst serial killer I ever dealt with': The confession of Joseph Paul Franklin". www.fox19.com. Archived from the original on August 7, 2020. Retrieved May 30, 2020. https://www.fox19.com/2020/02/18/worst-serial-killer-i-ever-dealt-with-confession-joseph-paul-franklin/
"Understanding Pragmatic Mission Killers". Psychology Today. Archived from the original on January 20, 2021. Retrieved September 1, 2020. https://www.psychologytoday.com/blog/wicked-deeds/201809/understanding-pragmatic-mission-killers
Ramsey, Nancy (May 25, 2004). "Out of Iran, a chilling truth". Los Angeles Times. Archived from the original on November 14, 2022. Retrieved May 17, 2023. https://www.latimes.com/archives/la-xpm-2004-may-25-et-ramsey25-story.html
Bartol & Bartol 2004, p. 146. - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Curt R. Bartol; Anne M. Bartol (2008). Introduction to Forensic Psychology: Research and Application. Sage. pp. 285–286. ISBN 978-1-4129-5830-1. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-4129-5830-1
Myers et al. 1993, pp. 435–451. - Myers, Wade C.; McElroy, Ross; Burton, Karen; Recoppa, Lawrence (1993). "Malignant Sex and Aggression: An Overview of Serial Sexual Homicide". Bulletin of the American Academy of Psychiatry and the Law. 21 (4): 435–451. PMID 8054674. https://pubmed.ncbi.nlm.nih.gov/8054674
Bartol & Bartol 2004, p. 146, Holmes & Holmes 2001, p. 163, Dobbert 2004, pp. 10–11 - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Dobbert 2004, p. 10-11. - Dobbert, Duane L. (2004). Halting the Sexual Predators Among Us: Preventing Attack, Rape, and Lust Homicide. Greenwood. ISBN 9780275978624. Archived from the original on September 1, 2016. Retrieved February 27, 2016. https://books.google.com/books?id=79BtniCkcLsC&pg=PP1
Giannangelo 2012, Fulero & Wrightsman 2008, Dvorchak & Holewa 1991 - Giannangelo, Stephen J. (2012). Real-life Monsters: A Psychological Examination of the Serial Murderer. ABC-CLIO. ISBN 9780313397844. Archived from the original on January 20, 2021. Retrieved November 21, 2020. https://books.google.com/books?id=zLgAQNc_HXwC&q=0313397848
MacCormick 2003, p. 431. - MacCormick, Alex (2003). The Mammoth Book of Maneaters: Over 250 Terrifying True Accounts of Predators from Pre-history to the Present. Running Press. ISBN 9780786711703. Archived from the original on January 20, 2021. Retrieved November 21, 2020. https://books.google.com/books?id=fVikswEACAAJ&q=0786711701
Dobbert 2004, p. 11. - Dobbert, Duane L. (2004). Halting the Sexual Predators Among Us: Preventing Attack, Rape, and Lust Homicide. Greenwood. ISBN 9780275978624. Archived from the original on September 1, 2016. Retrieved February 27, 2016. https://books.google.com/books?id=79BtniCkcLsC&pg=PP1
Curt R. Bartol; Anne M. Bartol (2008). Introduction to Forensic Psychology: Research and Application. Sage. pp. 285–286. ISBN 978-1-4129-5830-1. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-4129-5830-1
Bartol & Bartol 2004, p. 146, Howard & Smith 2004, p. 4 - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Howard & Smith 2004, p. 4. - Howard, Amanda; Smith, Martin (2004). River of Blood: Serial Killers and Their Victims. Universal. ISBN 978-1-58112-518-4.
Graysmith 2007, pp. 54–55. - Graysmith, Robert (2007). Zodiac (Reissue ed.). Berkley. ISBN 978-0-425-21218-9. https://archive.org/details/zodiac00gray
"A Deal With the Devil?". 60 Minutes. October 14, 2004. Archived from the original on October 18, 2013. Retrieved June 28, 2008. https://www.cbsnews.com/news/a-deal-with-the-devil-14-10-2004/
Mitchell 2006, pp. 207–208. - Mitchell, Corey (2006). Evil Eyes. Pinnacle Books. ISBN 9780786016761. https://books.google.com/books?id=eQFezeQkRFMC&pg=PT1
Curt R. Bartol; Anne M. Bartol (2012). Criminal & Behavioral Profiling. Sage Publications. pp. 197–199. ISBN 978-1-4522-8908-3. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-4522-8908-3
Curt R. Bartol; Anne M. Bartol (2008). Introduction to Forensic Psychology: Research and Application. Sage. pp. 285–286. ISBN 978-1-4129-5830-1. Archived from the original on January 20, 2021. Retrieved September 1, 2020. 978-1-4129-5830-1
Bartol & Bartol 2004, p. 146, Schlesinger 2000, p. 276, Holmes & Holmes 2000, p. 41 - Bartol, Curt R.; Bartol, Anne M. (2004). Introduction to Forensic Psychology: Research and Application. SAGE Publications. ISBN 978-1-4129-5830-1. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=on2XfplaMTQC&pg=PP1
Holmes & Holmes 2000, p. 44. - Holmes, Ronald M; Holmes, Stephen T (2000). Mass murder in the United States. Prentice Hall. ISBN 978-0-13-934308-7.
Holmes & Holmes 2000, p. 43. - Holmes, Ronald M; Holmes, Stephen T (2000). Mass murder in the United States. Prentice Hall. ISBN 978-0-13-934308-7.
"Dorothea Puente, Killing for Profit – Easy Money". Trutv.com. Archived from the original on January 14, 2010. Retrieved July 29, 2010. https://web.archive.org/web/20100114083906/http://www.trutv.com/library/crime/notorious_murders/women/puente/9.html
Zagros Madjd-Sadjadi (2013). The Economics of Crime. Business Expert Press. p. 162. ISBN 978-1-60649-583-4. Archived from the original on January 20, 2021. Retrieved August 30, 2020. 978-1-60649-583-4
Holmes & Holmes 1998, p. 7. - Holmes, Ronald M.; Holmes, Stephen T. (1998). Serial Murder (Second ed.). Sage. ISBN 978-0-7619-1367-2. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=ol24tui7vo8C&pg=PP1
David Wilson; Elizabeth Yardley; Adam Lynes (2015). Serial Killers and the Phenomenon of Serial Murder: A Student Textbook. Waterside Press – Drew University. p. 43. ISBN 978-1-909976-21-4. Archived from the original on January 20, 2021. Retrieved August 30, 2020. 978-1-909976-21-4
David Wilson; Elizabeth Yardley; Adam Lynes (2015). Serial Killers and the Phenomenon of Serial Murder: A Student Textbook. Waterside Press. p. 43. ISBN 978-1-909976-21-4. Archived from the original on January 20, 2021. Retrieved August 30, 2020. 978-1-909976-21-4
Egger, Steven A. (2000). "Why Serial Murderers Kill: An Overview". Contemporary Issues Companion: Serial Killers.
Peck & Dolche 2000, p. 255. - Peck, Dennis L.; Dolche, Norman Allan (2000). Extraordinary Behavior: A Case Study Approach to Understanding Social Problems. Greenwood. ISBN 978-0-275-97057-4. Archived from the original on May 14, 2019. Retrieved February 19, 2018. https://books.google.com/books?id=rDBqd3zKGoYC&pg=PP1
Scott, Shirley Lynn. "What Makes Serial Killers Tick?". truTV. Archived from the original on July 28, 2010. Retrieved January 9, 2011. https://web.archive.org/web/20100728094415/http://www.trutv.com/library/crime/serial_killers/notorious/tick/victims_1.html
"Dennis Rader". Biography. A&E Television Networks. Archived from the original on March 18, 2019. Retrieved January 1, 2016. http://www.biography.com/people/dennis-rader-241487
Holmes & Holmes 2010, pp. 55–56. - Holmes, Ronald M.; Holmes, Stephen T. (2010). Serial murder (3rd ed.). Thousand Oaks, Sage, California. ISBN 978-1-4129-7442-4. https://archive.org/details/serialmurder0000holm_c5e3
"Serial Killers". Federal Bureau of Investigation. Archived from the original on May 20, 2010. Retrieved May 26, 2010. https://web.archive.org/web/20100520203225/http://fbilibrary.fbiacademy.edu/bibliographies/serialkillers.htm
Claus & Lindberg 1999, pp. 427–435. - Claus, C.; Lindberg, L. (1999). "Serial Murder as a 'Shariar Syndrome'". The Journal of Forensic Psychiatry. 10 (2): 427–435. doi:10.1080/09585189908403694. https://doi.org/10.1080%2F09585189908403694
Castle & Hensley 2002, pp. 453–465, DeFronzo & Prochnow 2004, pp. 104–108 - Castle, T.; Hensley, C. (2002). "Serial killers with military experience: Applying learning theory to serial murder" (PDF). International Journal of Offender Therapy and Comparative Criminology. 46 (4): 453–465. doi:10.1177/0306624x02464007. PMID 12150084. S2CID 35278358. Archived from the original (PDF) on October 27, 2011. https://web.archive.org/web/20111027101009/http://www.shsu.edu/~stdrem26/pictures/MilitarySerialKillers.pdf
Richardson, Christy; Waldrop, Judith (2003). "Veterans: 2000" (PDF). U.S. Census Bureau. p. 5. Archived (PDF) from the original on August 25, 2011. Retrieved July 13, 2011. https://www.census.gov/prod/2003pubs/c2kbr-22.pdf
Woodhead et al. 2009, pp. 50–54. - Woodhead, Charlotte; Sloggett; Bray, Issy; Bradbury, Jason; McManus, Sally; Meltzer, Howard; Brugha, Terry; Jenkins, Rachel; Greenberg, Neil; Wessely, Simon; Fear, Nicola (2009). "An Estimate of the Veteran Population in England: Based on data from the 2007 Adult Psychiatric Morbidity Survey". Population Trends. 138 (1): 50–54. doi:10.1057/pt.2009.47. PMID 20120251. S2CID 8483631. https://doi.org/10.1057%2Fpt.2009.47
"Estimated population of Canada, 1605 to present". Statistics Canada. July 6, 2009. Archived from the original on June 30, 2019. Retrieved May 23, 2011. http://www.statcan.gc.ca/pub/98-187-x/4151287-eng.htm#table3
"The Veteran Population and the People We Serve". Veterans Affairs Canada. 2003. Archived from the original on October 1, 2012. Retrieved July 13, 2011. https://web.archive.org/web/20121001151839/http://www.veterans.gc.ca/eng/sub.cfm?source=department%2Freports%2Ffiveyearplan03%2Fplan03_population
Castle & Hensley 2002. - Castle, T.; Hensley, C. (2002). "Serial killers with military experience: Applying learning theory to serial murder" (PDF). International Journal of Offender Therapy and Comparative Criminology. 46 (4): 453–465. doi:10.1177/0306624x02464007. PMID 12150084. S2CID 35278358. Archived from the original (PDF) on October 27, 2011. https://web.archive.org/web/20111027101009/http://www.shsu.edu/~stdrem26/pictures/MilitarySerialKillers.pdf
"Social Learning and Serial Murder". www.deviantcrimes.com. Archived from the original on January 4, 2009. Retrieved January 15, 2022. https://web.archive.org/web/20090104221523/http://www.deviantcrimes.com/serialmurder_sociallearning.htm
Hamamoto 2002, pp. 105–120. - Hamamoto, D (2002). "Empire of death: militarized society and the rise of serial killing and mass murder". New Political Science. 24 (1): 105–120. doi:10.1080/07393140220122662. S2CID 145617529. https://doi.org/10.1080%2F07393140220122662
Atwood 1992. - Atwood, Donald J. (February 25, 1992). "Department of Defense Directive AD-A272 176: Use of Deadly Force and the Carrying of Firearms by DoD Personnel Engaged in Law Enforcement and Security Duties" (PDF). DoD. Archived (PDF) from the original on March 28, 2018. Retrieved July 13, 2011. http://apps.dtic.mil/dtic/tr/fulltext/u2/a272176.pdf
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
Sanchez, Shanell. "1.1 Crime and the Criminal Justice System". Introduction to the American Criminal Justice System. Open Oregon Educational Resources. Archived from the original on September 9, 2022. Retrieved September 9, 2022. https://openoregon.pressbooks.pub/ccj230/chapter/goals/
Keppel 2000 - Keppel, Robert D. (2000). Serial Murder: Future Implications for Police Investigations. Authorlink Pr. ISBN 9781928704188.
Boyne, E. Serial Homicide Collaborative Brings Research Data Together. CJ Update: A Newsletter for Criminal Justice Educators. Retrieved from https://tandfbis.s3.amazonaws.com/rt-files/docs/SBU3/Criminology/CJ%20UPDATE%20FallWinter%202014.pdf
Elink-Schuurman-Laura, Kristin. "Radford/FGCU Serial Killer Database Project – Justice Studies FGCU". FGCU Department of Justice Studies. Archived from the original on May 8, 2013. Retrieved February 2, 2013. https://web.archive.org/web/20130508064156/http://skdb.fgcu.edu/info.asp
"FDIAI 52nd Annual Conference". Archived from the original on October 31, 2012. Retrieved February 2, 2013. https://web.archive.org/web/20121031044256/http://fdiai.org/2012%20Conference%20Daily%20Schedule.htm
Aamodt, Mike. "Serial Killer Statistics" (PDF). Radford University. Archived (PDF) from the original on March 9, 2013. Retrieved February 6, 2013. http://maamodt.asp.radford.edu/Serial%20Killer%20Information%20Center/Serial%20Killer%20Statistics.pdf
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
Guillen 2007 - Guillen, Tomas (2007). Serial Killers: Issues Explored Through the Green River Murders. Pearson Prentice Hall. ISBN 9780131529663. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=QJnyAAAAMAAJ
Guillen 2007 - Guillen, Tomas (2007). Serial Killers: Issues Explored Through the Green River Murders. Pearson Prentice Hall. ISBN 9780131529663. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=QJnyAAAAMAAJ
Egger 1990 - Egger, Steven A. (1990). Serial Murder: An Elusive Phenomenon. Praeger Publishers Inc. ISBN 9780275929862.
Egger 1990 - Egger, Steven A. (1990). Serial Murder: An Elusive Phenomenon. Praeger Publishers Inc. ISBN 9780275929862.
Egger 1990 - Egger, Steven A. (1990). Serial Murder: An Elusive Phenomenon. Praeger Publishers Inc. ISBN 9780275929862.
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Keppel 2000 - Keppel, Robert D. (2000). Serial Murder: Future Implications for Police Investigations. Authorlink Pr. ISBN 9781928704188.
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Guillen 2007 - Guillen, Tomas (2007). Serial Killers: Issues Explored Through the Green River Murders. Pearson Prentice Hall. ISBN 9780131529663. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=QJnyAAAAMAAJ
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Keppel 2000 - Keppel, Robert D. (2000). Serial Murder: Future Implications for Police Investigations. Authorlink Pr. ISBN 9781928704188.
Egger 2002 - Egger, Steven A. (2002). The Killers Among Us: An Examination of Serial Murder and Its Investigation. Prentice Hall. ISBN 9780130179159. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=MqLyAAAAMAAJ
Keppel 2000 - Keppel, Robert D. (2000). Serial Murder: Future Implications for Police Investigations. Authorlink Pr. ISBN 9781928704188.
Keppel 2000 - Keppel, Robert D. (2000). Serial Murder: Future Implications for Police Investigations. Authorlink Pr. ISBN 9781928704188.
"Serial Murder". Federal Bureau of Investigation. Archived from the original on October 28, 2010. Retrieved June 3, 2011. https://www.fbi.gov/stats-services/publications/serial-murder
Guillen 2007 - Guillen, Tomas (2007). Serial Killers: Issues Explored Through the Green River Murders. Pearson Prentice Hall. ISBN 9780131529663. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=QJnyAAAAMAAJ
Guillen 2007 - Guillen, Tomas (2007). Serial Killers: Issues Explored Through the Green River Murders. Pearson Prentice Hall. ISBN 9780131529663. Archived from the original on January 20, 2021. Retrieved September 9, 2020. https://books.google.com/books?id=QJnyAAAAMAAJ
"Getting away with murder". minotdailynews.com. Archived from the original on April 10, 2021. Retrieved April 10, 2021. https://www.minotdailynews.com/opinion/national-columnists/2020/01/getting-away-with-murder/
Ramsland, Katherine; Karen Pepper. "Serial Killer Culture". Tru.tv Crime Library. Archived from the original on January 6, 2010. Retrieved April 2, 2010. https://web.archive.org/web/20100106080546/http://www.trutv.com/library/crime/criminal_mind/psychology/s_k_culture/1.html
Robinson, Bryan (January 7, 2006). "Serial Killer Action Figures For Sale". ABC News. Archived from the original on June 28, 2011. Retrieved April 1, 2010. https://abcnews.go.com/US/story?id=91786&page=1
Ramsland, Katherine; Karen Pepper. "Serial Killer Culture". Tru.tv Crime Library. Archived from the original on June 1, 2009. Retrieved April 2, 2010. https://web.archive.org/web/20090601230659/http://www.trutv.com/library/crime/criminal_mind/psychology/s_k_culture/6.html