Nine months before Aileen Wuornos was executed, an opera about her life premiered in San Francisco. Wuornos was one of several artistic works, including the 2003 film Monster, that she inspired. The opera, like the movie, portrayed Wuornos as undeniably violent but also worthy of understanding—a tragic figure, like Medea.
The opera’s composer, Carla Lucero, also raised the question of why Wuornos, as a female serial killer, should seem so unusual. If Wuornos were a man, Lucero suggested, her crimes, though still horrendous, would have been considered more normal. “Men are expected to lash out, to be violent, to defend themselves, to retaliate,” Lucero wrote in a synopsis of the opera. “Is it so shocking that a woman, horribly abused as a child and later as an adult, killed in self-defense and then had knee-jerk reactions to threats of violence to her person time and again? Men returning from war call it shell-shock. Yet women have been in the trenches for centuries. Aileen Wuornos’s actions are not to be applauded, though there is a message loud and clear: Abuse is cyclical.”1 Lucero also wrote of another lesson from Wuornos’s life: “Unrequited fury will inevitably become unbearable.”2
Lucero’s need to compare Wuornos’s behavior to a man’s proved that, to many, Wuornos—though introduced to mainstream America through the movies, the media, and even an opera—remained an exception. She was not seen as the latest in a long line of female serial killers, dating to the 1800s in the United States, and as far back as ancient Rome, but as a murderous freak who, thankfully, had no counterparts, then or now. Even the New York Times editorialized in 1991 that, Wuornos aside, women most definitely could not be serial killers. Such mayhem was the province of men. Certainly, wrote the Times, women had been known to kill multiple victims, but those women were not serial killers, because they killed only “when there was something to be gained—either money or retribution.”3 But killing for the sake of killing? The Times not only defined a serial killer by that concept, but said it only applied to men, and never women. “What the press, psychologists and the F.B.I. mean by ‘serial killer’ is a man—a man who kills because he likes to,” the Times wrote.4
The Times’s editorial nonetheless accurately described the sentiment that had kept American popular culture from recognizing that women could be serial killers, too. Women are said to be the caregivers, the keepers of the hearth, the members of the fairer sex, who are somehow disinclined to kill and especially disinclined to kill and kill again. “They’re much more apt to wring their hands than other people’s necks,”5 the Times wrote. As Eric W. Hickey, who wrote one of the first articles on female serial killers, in the mid-1980s, said, “We have a stereotype of women [as serial killers]—when they do it, we think they are more evil than men.”6 Or, in the words of Marissa A. Harrison, an evolutionary psychologist at the Pennsylvania State University at Harrisburg, “I think society is in denial that women are capable of such hideousness.”7 Marjorie Diehl-Armstrong understood the bias. Though she never offered an opinion on gender and serial killers, she linked certain crimes—such as murder using an explosive device—to masculinity, and tried to use the correlation as a defense. She said the bombing death of Brian Wells was a crime that only a man could execute, and she said she didn’t rob banks.8 “A woman doesn’t do this crime,” she said of Wells’s death.9 “I don’t ever think I know a woman who would do this. It is a guy’s crime.”10
Such stereotypes, for a time, infected the study of serial killers with sexism. While women were accepted to be capable of multiple killings, they were not considered serial killers unless they killed like a man, such as in the case of Aileen Wuornos. Even a retired FBI behavioral profiler is once said to have stated, at a conference in 1998, that “there are no female serial killers.”11 Marjorie Diehl-Armstrong believed that theory as well. In November 2014, when she was awaiting prosecution in the Pizza Bomber case, in which she was connected to her third homicide victim, she declared: “I am not a serial fucking killer. As far as I know, no woman has been a serial killer.”12
This has never been the reality; what has changed is the recognition that a woman can be a serial killer on her own terms, without having to achieve some kind of male standard. Women can be just as brutal as men, but in different ways. As Hickey has found, “the real issue is method.”13 Female serial killers, such as Nannie Doss, frequently poison their victims, a means of murder that is much less violent than gunfire but certainly no less effective. No matter how they kill, women are capable of serial murder, and, in the words of Hickey, “To say that a woman cannot be a ‘true’ serial killer unless she acts like a male is myopic.”14
Such thinking is also risky. It establishes the mind-set that can let a woman get away with murder—a mind-set that can encourage reluctance, on behalf of law enforcement, to investigate a woman as a serial killer or to investigate a murder committed by a woman as something other than self-defense or an isolated crime of passion.15 Because female serial killers often use more secretive methods to murder their victims, such as poisoning, suffocation, and staged accidents,16 investigators can be more inclined to misclassify homicides as accidental deaths. For Amanda Farrell, a professor at Marymount University who, like Hickey and Harrison, has studied female serial killers in detail, “These misclassifications, combined with the hesitancy to accuse a woman, particularly if the victim was someone close to her, of murder can stall the investigation before it begins, leading to the loss of valuable evidence and information.”17
In Sacramento, California, in 1988, Eric Hickey consulted with the FBI on a case of a woman who ran a boarding house where police found the remains of seven bodies. The police suspected the operator of the boarding house, a sixty-year-old woman by the name of Dorothea Puente, had poisoned the residents, who were elderly and disabled, to steal their Social Security checks. The FBI agents declined to call Puente’s case that of a serial killer. “Of course, it was,” Hickey recalled. “They just didn’t recognize it then. Women were not considered to be predators that way.”18 Puente was accused of murdering nine people between 1982 and 1988; was found guilty in three of the deaths in 1993; and was serving two life sentences when she died in prison in 2011, when she was eighty-two years old. One of her first victims died in 1982 from an apparent overdose of codeine and Tylenol. The boarder, Puente said, was depressed because her husband had died of cancer. Police initially treated the death as a suicide.19
The police likely would not have made such an error if the victim had died violently, such as from a gunshot wound, or had been sexually molested before or after death. Investigators immediately would have suspected a homicide and, if the death fit a pattern, suspected a man as the serial killer, rather than a woman. With few exceptions, male serial killers employ much more violent methods than do women, and, unlike female serial killers, they will more frequently sexually molest their victims before or after death. “We rarely, if ever, hear of a female ‘Jack the Ripper,’” Hickey has written. “Women who kill serially generally use poisons to dispose of their victims and are not associated with the sexual attacks, tortures, and violence of their male counterparts.”20 Female serial killers, as many researchers have found, tend to be “quiet killers” whose less violent methods of murder might be said to conform with their feminine and traditionally less violent natures. By poisoning their victims or suffocating them or staging their deaths, female serial killers prefer “not to allow their aggression to manifest in visible violence or brutality. It is unlikely you would find a woman sexually assaulting a corpse or engaging in cannibalistic or vampiric activities”21 (with some exceptions, such as Elizabeth Báthory).
Researchers have used Freudian analysis to explain why men and women tend to kill so differently, and they have used evolutionary theory: Men are generally thought to kill for sex, while women are generally thought to kill for resources, such as money. “Women’s motives for serial murder,” Hickey has found, “appear to center on financial security, revenge, enjoyment, and sexual stimulation.”22 Murder, whether serial or otherwise, can represent an extreme and unlawful expression of basic human drives. The male, able to produce unlimited amounts of sperm, seeks “multiple sexual opportunities,” while the female, able to produce a limited amount of eggs, seeks “a stable, committed partner with sufficient resources.”23 These subconscious urges, combined with society’s stereotypes of feminine and masculine behavior, can also engender empathy or understanding for a female serial killer—reactions that most communities would be far less likely to express for a male serial killer, especially one who sexually violates his victims. In the case of a woman such as Aileen Wuornos, victimized and oppressed throughout her life, her murders, though serial, can seem justified, as in the opera that bears her name. Why would a woman kill and kill again unless she was provoked or so desperate that murder, even serial murder, would seem her only way out?
The nicknames bestowed on female killers over the years reflect the disparity between how society views them compared to male killers. While male killers are known as Jack the Ripper, the Night Stalker, and the Boston Strangler, female serial killers have been known by monikers that soften their images: Giggling Grandma, Sister Amy, Belle of Indiana, Duchess of Death, Old Shoe Box Annie, Beautiful Blonde Killer, Black Widow, Death Angel, the Highway Hooker, Damsel of Death.
No matter what their nicknames, motives, drives, or methods, female serial killers represent a challenging class of criminal to study. Group-based research, rather than research that focuses on a single female serial killer, is limited; much of the most detailed analyses has occurred over the past several decades. The lack of research before then is most likely due to the misconception that women were not capable of serial murder. Studying a group of female serial killers was unthinkable before the late 1980s and early 1990s because such a group was not thought to exist. Eric Hickey pioneered the field in 1991, when he published a comprehensive study that examined the case histories of sixty-four female serial killers. Twenty-four years later, in 2015, Marissa Harrison and colleagues examined the case histories of sixty-four female serial killers (the identical numbers are a coincidence) to help update the scholarly understanding of women who kill repeatedly.
Harrison et al.’s work offers a general statistical profile of female serial killers, based on their analysis of the sixty-four women, who killed between 1821 and 2008. The majority of them were white (88.7 percent), married (54.2 percent), middle class (55.3 percent), and with a mean age of thirty-two, though “at the time of their first killings, they ranged in age from 16 to 65, evincing considerable variation.”24 Most of the women in Harrison’s study had college or professional degrees (34.6 percent), though 15.4 percent were high school graduates and another 30.8 percent were high school dropouts. Information on intellectual capability was limited to a quarter of the sixty-four women; among those, half were believed to have average intelligence, 12.5 percent high intelligence, and 28.6 percent were believed to have intellectual disabilities or deficiencies. Six of the women, or 9.4 percent, were found to have suffered severe childhood illnesses, such as head trauma or scarlet fever.25
Psychological trauma was prevalent among the sixty-four women. Based on the available information, 31.5 percent were physically or sexually abused, 23.4 percent suffered from drug or alcohol abuse, and 39.1 percent suffered from severe mental illness, including two women who were diagnosed with schizophrenia, two with antisocial personality disorder, and two with major depressive disorder.26 Though nearly 40 percent of Harrison et al.’s subjects suffered from mental illness, and 12.4 percent were institutionalized,27 none was found to be legally insane—a designation that covers only 2 to 3 percent of all serial killers.28 Most of the women in the study killed victims they knew—victims who were aware of the killer’s mental and physical infirmities. While female serial killers, like their male counterparts, have been known to stalk strangers before killing them, the majority of women Harrison and her colleagues studied, 62.5 percent, knew their victims. A total of 43.8 percent killed their biological children, while another 29.7 percent killed their husbands, fiancés, or boyfriends.29
The victims of female serial killers, in most instances, are passive—they do not engage in behavior that helps bring about their death. Harrison et al., Hickey, and other researchers have found that many of the victims are children and others also had little to do with instigating their deaths. “Female offenders almost exclusively killed victims who were categorized as low-facilitation homicides (the victims played a small role, if any, in their own deaths).”30 Also among these helpless victims are the elderly and residents of nursing homes—victims whom female serial killers typically poison through drug overdoses and other means. One female serial killer, Jane Toppan, a nurse in Boston, is known to have killed thirty-one hospital patients and was suspected of killing as many as seventy more between 1887 and 1901. Her method of killing was a lethal injection of morphine.31 At her trial, Toppan, who was found not guilty by reason of insanity, said: “This is my ambition—to have killed more people—more helpless people—than any man or woman has ever killed.”32 Toppan was a well-regarded nurse (though she was obsessed with autopsies). Like many female serial killers, Toppan was, until she was charged, seen as normal: “Your next-door neighbor.”33 But a disturbed next-door neighbor nonetheless, one of any number of serial murderers who, upon closer examination, “appear to be unhappy, unsuccessful individuals who choose to make their mark on society through violent means.”34
Jane Toppan is what researchers of female serial killers call an angel of death—a woman, such as a nurse or a mother, who is in a nurturing occupation and generally kills helpless victims, including patients in her care. Other categories of female serial killers are sexual predators, revenge killers, profit or crime killers, team killers, killers of questionable sanity, and unsolved murderers.35 The category of angel of death is also included in a larger class of female serial killers—the power seeker. The other three classes, or typologies, are hedonistic, or those women, such as black widows, who kill for money, comfort, or the thrill; visionaries, who kill at the command of visions and other hallucinations; and missionaries, or those who murder “to rid the world of ‘undesirables.’”36
The members of these typologies and categories for serial killers have different personalities and different motives, but they share many traits—women and men both. “The women,” Hickey has written, “tended to be insincere, amoral, impulsive, prone to exercise manipulative charisma and superficial charm, without conscience, and with little insight, because they failed to learn from their mistakes.”37 These traits—whether a male or female serial killer exhibits them—are generally attributed to psychopaths. As the FBI defines it, psychopathy is “manifested in people who use a mixture of charm, manipulation, intimidation, and occasionally violence to control others, in order to satisfy their own selfish needs.”38
To measure an individual’s level of psychopathy, behaviorists, investigators, and others use the Psychopathy Check List Revised, which Robert Hare, a Canadian criminal psychologist, developed in the 1980s and early 1990s. The check list is a tool to gauge the level of psychopathy in four areas: interpersonal, affective, lifestyle, and antisocial. The FBI, in its 2005 manual Serial Murder, provides thorough summaries of the traits that typically fall under each category.
The interpersonal traits include glibness, superficial charm, a grandiose sense of self-worth, pathological lying, and the manipulation of others. The affective traits include a lack of remorse and/or guilt, shallow affect, a lack of empathy, and failure to accept responsibility. The lifestyle behaviors include stimulation-seeking behavior, impulsivity, irresponsibility, parasitic orientation, and a lack of realistic life goals. The anti-social behaviors include poor behavioral controls, early childhood behavior problems, juvenile delinquency, revocation of conditional release, and criminal versatility. The combination of these individual personality traits, interpersonal styles, and socially deviant lifestyles are the framework of psychopathy and can manifest themselves differently in individual psychopaths.39
Psychopaths share many personality traits with sociopaths, though the two are different in many ways. Both sociopathy and psychopathy are antisocial personality disorders, and psychopaths and sociopaths have no remorse and no regard for the rights of others. But sociopaths tend to be more nervous, agitated, and outwardly disturbed, and live on the “fringes of society,” while psychopaths are apt to be charming, manipulative, more highly educated, and better able to form long-standing relationships.40 Sociopaths who are serial killers tend to operate on impulse and with little planning. Psychopaths are more methodical in their killing, and often have contingency plans. “Unlike their sociopathic counterparts, psychopathic criminals are cool, calm, and meticulous.”41
Not all sociopaths and psychopaths are serial killers and not all serial killers are sociopaths or psychopaths. Psychopathy, according to the FBI, does not alone explain a serial killer’s motives. But serial killers who are psychopaths have no value for human life and often treat killing as a game, particularly when a serial killer stalks his or her victims. For a serial killer, victims can be like trophies.
A serial killer’s psychopathic traits also represent his or her vulnerabilities—a theme that runs through The Silence of the Lambs and other fictional psychological thrillers about serial killers. Psychopaths often have distinct criminal behaviors that can provide clues to link serial killings. Investigators often can take advantage of a serial killer’s psychopathic traits to catch a serial killer or to get a serial killer to admit to crimes in an interview. As the FBI has observed: “Psychopaths are not sensitive to altruistic interview themes, such as sympathy for their victims or remorse/guilt over their crimes. They do possess certain personality traits that can be exploited, particularly their inherent narcissism, selfishness, and vanity. Specific themes in past successful interviews of psychopathic serial killers focused on praising their intelligence, cleverness, and skill in evading capture.”42 Like many people, psychopathic serial killers enjoy talking about themselves, and they like to hear that they are the best at what they do—even if their career involves killing.
Among female serial killers, Marjorie Diehl-Armstrong is a hybrid. Her personality included attributes of both a sociopath and a psychopath: impulsive yet methodical, haphazard but also careful, seriously mentally disturbed in some instances but clearly sane in others. Like a sociopath, she had few friends who were regulars in society, but like a psychopath she was highly intelligent and well educated. As for typologies, according to the evidence against her: she was a hedonistic black widow who killed for money, but also a missionary murderer who killed to cleanse the world of men she thought beneath her. She can also be considered a revenge killer and an angel of death: she killed to get back at her boyfriends, but she killed them when, according to the police, they were in a helpless state—when they were on a couch or when they were sleeping.
Above all, no matter whom she killed or why, Diehl-Armstrong saw herself as a brilliant victim, a smart and worldly woman who was trapped in situations beyond her control. She was never the problem. She had the skills needed to excel in life. Her problem was men, and specifically the men she said were attracted to her. They were abusive imbeciles who would have amounted to nothing without her. And what did she get in return? Trouble and wretchedness.
Of her problematic relationships with men, she said, “I killed abusive boyfriends who tried to kill me in my own home.”43
“I am always between dumb and dumber and a rock and a hard place,” she liked to say.44 Another of her favorite lines was, “I’m the pickle in the middle with hell on all sides.”45
This narcissism and grandiosity are among the many attributes of Diehl-Armstrong’s psychopathy. Eric Hickey, in an analysis of Diehl-Armstrong, said she would rank “fairly high” on the scale of Robert Hare’s Psychopathy Check List Revised. Hickey said Diehl-Armstrong’s case is similar to that of Aileen Wuornos and that Diehl-Armstrong was highly unusual among female serial killers, as Wuornos also was highly unusual. Diehl-Armstrong, like Wuornos, had an antipathy toward men; and Diehl-Armstrong, when she worked alone, also chose a method of murder—gunfire—that is more typically common among male serial killers. When Diehl-Armstrong worked with others, in the Pizza Bomber case, the method—a bombing—was just as violent. (Among the sixty-four female serial killers Harrison studied, half used poison, 10.9 percent used guns, and none used explosives.46)
Hickey’s descriptions of Wuornos can apply to Diehl-Armstrong: “She was physically strong and could become very aggressive when provoked. She killed like a male, except for the fact that most of her victims were shot in the torso, which is more typical of female killers; males are prone to shoot into the victim’s head.”47 Hickey also wrote: “Aileen Wuornos was not the first female serial killer . . . but rather an anomaly. Wuornos was an atypical female serial killer. We have almost no documentation of anyone similar to Wuornos, and there is nothing to suggest we will see more like her in the foreseeable future.”48
Marjorie Diehl-Armstrong, Hickey said, is an exception. “She acts on her own and has no regard for human life.” When she was working alone, she was “not working under the guise or spell of another person,” he said. “That moves her into a special category—like Aileen Wuornos.”49 “She is more the outlier than the mainstream,” Hickey said of Diehl-Armstrong. “It is a very tragic case.”50