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Eye on Psi Chi: Summer 2016

Studying Female Serial Killers
Marissa A. Harrison, PhD, Penn State Harrisburg (PA)
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In 1901, Jane Toppan, a nurse, confessed to 31 murders, but it is thought that her victim count was much higher—perhaps as many as 100 patients died because she poisoned them. She is quoted as saying to other health care workers, “You and I will have a lot of fun seeing them die” (Newton, 1993). In this article, I’m going to talk about how I got started in female serial killer (FSK) research, ideas of why people are intrigued by serial murder and other morbid events, and what our investigation yielded out about these murderers—“lethal ladies” (as coined by Farrell, Keppel, & Titterington, 2011)—with respect to behavior and mental processes.
Sometimes it is students who set professors down research paths. When Erin Murphy, then an undergraduate dual psychology/criminal justice major at Penn State Harrisburg, approached me to study FSKs for her independent study, I was already part of a research team with Dr. Tom Bowers that studies mass murder. Although we planned to extend our investigation at some point to serial murderer psychology, Erin brought to my attention that very little research had been conducted on FSKs. I was definitely intrigued (and I did not want to pass up an opportunity to work with an outstanding student). Serial murder is fascinating, and the lack of attention to these female perpetrators makes the research pursuit even more interesting.
Indeed, researchers have pointed out that we humans commonly possess a morbid curiosity (Zuckerman, 2007; Zuckerman & Litle, 1985). Something about macabre events truly captivates us. Erika Frederick, a student in our clinical Master’s program, and I are currently exploring this phenomenon in college students. With so many media sources available to access morbid events, and with morbid entertainment abundant in our society (e.g., zombie and serial killer movies and television shows), we are aiming to see if morbid curiosity has increased in recent years.
There are many theories as to why morbid curiosity exists including an enjoyment of the sensations that epinephrine (adrenalin), norepinephrine, and dopamine create in our bodies when we experience fright (Zuckerman & Litle, 1985). Our bodies have evolved to prepare us to fight or to flee, and some of us are indeed sensation seekers. That is, we enjoy that “scared” feeling—that rush we feel from exciting events.
There is also the ultimate, evolutionary cause of morbid fascination. After all, it makes sense that, to facilitate survival, it is adaptive to pay close attention to that which can harm us or even kill us. I recall that, when Erin was giving class updates about her findings, other students wanted to know all the gory, disturbing details of the serial murders she had read about. I cannot unhear the story of a woman who poisoned her four children and stuffed their bodies in a closet.
What our research team discovered in our investigations really does seem to intrigue the public. We’ve been interviewed by many media outlets—I was delighted to have been asked to write this piece— because people truly want to learn about and understand the makings, motives, means, and crimes of serial killers.
In our exploration of FSKs, and in subsequent presentations of the material, Erin and I and our coauthors have found what Holmes, Hickey, and Holmes (1991) noted to be true—that most people have heard of “popular” male serial killers (MSKs) such as Ted Bundy and Jeffrey Dahmer. My guess is that more people can name John Wayne Gacy’s alter ego, Pogo the Clown, before they could name FSKs such as Belle Gunness, Kristen Gilbert, and Jane Toppan, who were no less deadly.
It is possible that research on FSKs is lacking and that most people cannot name any FSK besides Aileen Wuornos because people think women are incapable of committing these heinous acts (SchurmanKauflin, 2000). They are dead wrong because about one out of every six serial killers is a woman, mirroring general homicide trends (Hickey, 2010). Interestingly, Wuornos’s crimes, featured in the movie Monster (Theron et al., 2003), do not demonstrate the patterns of a typical FSK.
Although research on FSKs is relatively rare, some investigators have explored the topic. Criminologist Eric Hickey wrote one of the best books on serial killings, Serial Murderers and Their Victims. He interviewed and/or studied case files of 64 FSKs who committed their crimes in the United States. His research painted an alarming picture of women who poisoned, stabbed, shot, and drowned men, women, and children. Most were White, murdered more family members than strangers, and typically killed from seven to 10 victims (Hickey, 1991, 2010). Kelleher and Kelleher (1998) studied an international sample of 100 FSKs and produced results similar to Hickey’s, noting that most FSKs murdered for financial gain. Other researchers and teams explored this phenomenon, and although they had solid methodology and yielded similar results, they had smaller sample sizes (Farrell et al., 2011; SchurmanKauflin, 2000). Of note, both Farrell et al’s (2011) and Schurman-Kauflin’s (2000) studies underscored that, ironically, nursing and caretaking were professions largely overrepresented among FSKs.
We sought to study the means, motives, and makings of FSKs with a larger, more recent sample. We also endeavored to study the psychology of FSKs— something heretofore largely ignored in FSK literature. I am an evolutionary (experimental) psychologist, and Erin was an undergraduate student (she is now a clinical M.A. student), so we invited three clinicians to work with us on the project: my Penn State Harrisburg colleague and forensic “teammate” Dr. Tom Bowers, Lavina Ho (now a Ph.D. student at Ole Miss), and Claire Flaherty (Penn State Hershey Medical College).
We used the mass-media method of data collection. We initially consulted to derive FSK names, and we used verifiable news reports to collect data on perpetrators, victims, and crimes. This method of data collection follows the approach used in Harrison and Bowers (2010), and in other similar studies (Farrell et al., 2011; Keeney & Heide, 1994; Messing & Heeren, 2009). Of note, we found to be excellent resource; it was 100% accurate.
It is important to stress that our data collection method could not derive information about every variable for every woman. We underscore that absence of evidence is not evidence of absence. That is, our data rely on what newspapers and other media outlets have chosen to report. It may be the case, then, that some variables herein are underreported.
Like Hickey (1991), we found information about 64 FSKs who committed their crimes in the United States between 1821 and 2008. We do not know if these were the same 64 perpetrators because Hickey does not name FSKs in his book, and neither do we in our publication . . . one does not name subjects in nomothetic research.
I think the most striking of our findings is that nearly 40% of our sample experienced some form of mental illness. This is much higher than the estimate that one in four people in the United States suffer from mental illness. These women had a range of mental illnesses including posttraumatic stress disorder (PTSD), personality disorders, bipolar disorder, major depressive disorder, and Munchausen’s syndrome by proxy.
The other findings that stick with me are that more than half of the sample killed children, and about a quarter killed older or ill adults. That is, FSKs largely tend to kill people who have little or no chance of fighting back. Yet about 40% of FSKs worked in healthcare-related fields (e.g., nurses, nurse’s aides), and 22% worked in direct caregiving roles (e.g., babysitter, stayat-home mother). So, these women were killing the helpless people for whom they were trusted to care.
Here are some of our other findings from Harrison, Murphy, Ho, Bowers, and Flaherty (2015):

Physical and sexual abuse, childhood illness, and substance abuse were prevalent in their histories.

Most FSKs had earned college or professional degrees, or had at least some higher education.

Jobs besides caretaking spanned the gamut of career options, ranging from prostitute to Sunday School teacher.

Most were middle and upper class.

Most were reported to be average to above-average in attractiveness.

Mean age of first murder was 32, and they killed for seven years before they got caught.

Almost every FSK (92%) knew her victims.

Nearly two-thirds were related to their victims

Nearly a third killed their husbands or significant others.

About 44% killed their own children

These serial killers were “serial monogamists”; they were married on average twice and as many as seven times.

Like other researchers have noted, almost all FSKs were White, they most commonly killed with poison, and the most common motive for murder was profit.

Although most victims were men, FSKs most frequently targeted both sexes.

Most killed in suburbia.

Most went to prison for their crimes.
As an evolutionary psychologist, I took particular note of the pattern that these FSKs kill for money, and that MSKs kill for sex (other researchers have extensively studied MSKs, e.g., Hickey, 1991). This follows evolutionary prediction. In the ancestral environment, due to having relatively limited ova (i.e., limited reproductive opportunities), women would have strived to secure resources to promote the survival of their offspring and themselves. Because men have a virtually unlimited supply of sperm, throughout human evolution it would have been adaptive for men to seek many sexual (reproductive) opportunities (Trivers, 1972). Moreover, MSKs kill strangers whom they stalk (Hickey, 1991), and FSKs kill those whom they know—“gathering” those around them. It can therefore be argued that serial killers follow ancestral hunter-gatherer tendencies. Of course, I am not saying we evolved to be serial killers. However, this behavior, albeit aberrant, demonstrates that, at some deep level, our psychology is operating as it has over many, many millennia.
But if serial killing stems from an evolved reproductive drive, why would a woman kill her children? Good question. Buss (2008) described malfunctions of evolved psychological mechanisms. Most behaviors lie by the adaptive, optimal mean of polygenic traits, but the extremes such as killing are much exaggerated or much reduced levels of what is supposed to be normal behavior. Obviously, something has gone terribly wrong, and hopefully, we psychologists will endeavor to understand and to help.
So, what did we learn? Can we predict who will become a serial killer? No, we are not there yet, but at least we have some idea of makings and motives, and from these data, we underscore the importance of mental health research, treatment, and intervention. Future researchers should continue this line of investigation. Perhaps someday we can develop a preventative strategy, saving victims and helping the would-be killers themselves.
Buss, D. M. (2008). Evolutionary psychology: The new science of the mind (3rd ed.). Boston, MA: Pearson Education.
Farrell, A. L., Keppel, R. D., & Titterington, V. B. (2011). Lethal ladies: Revisiting what we know about female serial murderers. Homicide Studies, 15, 228–252. doi:10.1177/1088767911415938
Harrison, M. A., & Bowers, T. G. (2010). Autogenic massacre as a maladaptive response to status threat. Journal of Forensic Psychiatry and Psychology, 21, 916–932. doi:10.1080/1478994 9.2010.506618
Harrison, M. A., Murphy, E. A., Ho, L. Y., Bowers, T. G., & Flaherty, C. V. (2015). Female serial killers in the United States: Means, motives, and makings. Journal of Forensic Psychiatry and Psychology, 26, 383–406. doi:10.1080/14789949.2015.1007516
Hickey, E. W. (1991). Serial murderers and their victims (1st ed.). Belmont, CA: Thomson/Wadsworth.
Hickey, E. W. (2010). Serial murderers and their victims (5th ed.). Belmont, CA: Thomson/Wadsworth.
Holmes, S. T., Hickey, E. W., & Holmes, R. M. (1991). Female serial murderesses: Constructing differentiating typologies. Journal of Contemporary Criminal Justice, 7, 245–256. doi:10.1177/104398629100700405
Keeney, B. T., & Heide, K. M. (1994). Gender differences in serial murderers: A preliminary analysis. Journal of Interpersonal Violence, 9, 383–398. doi:10.1177/088626094009003007
Kelleher, M. D., & Kelleher, C. L. (1998). Murder most rare: The female serial killer. Westport, CT: Praeger.
Messing, J. T., & Heeren, J. W. (2009). Gendered justice: Domestic homicide and the death penalty. Feminist Criminology, 4, 170–188. doi:10.1177/1557085108327657
Newton, M. (1993). Hunting humans, volume 2: An encyclopedia of modern serial killers. New York, NY: Avon Books.
Schurman-Kauflin, D. (2000). The new predator: Women who kill. New York, NY: Algora Publishing. Theron, C., Damon, M., Peterson, C., Kushner, D., Wyman, B. (Producers), & Jenkins, P. (Director). (2003). Monster [motion picture]. United States: DEJ Productions.
Trivers, R. (1972). Paternal investment and sexual selection. In B. G. Campbell (Ed.), Sexual selection and the descent of man (pp. 136–179). Chicago, IL: Aldine-Atherton.
Zuckerman, M. (2007). Sensation seeking and risky behavior. Washington, DC: American Psychological Association.
Zuckerman, M., & Litle, P. (1985). Personality and curiosity about morbid and sexual events. Personality and Individual Differences, 7, 49–56. doi:10.1016/0191-8869(86)90107-8

Marissa A. Harrison, PhD, is an associate professor of psychology at Penn State Harrisburg. She received her PhD in biopsychology with a specialization in evolutionary psychology from the University at Albany, SUNY. Her research focuses on mate assessment, physical attraction, and sexual behavior. Most recently, her research applies evolutionary theory to understanding motivation of murder.


Copyright 2016 (Volume 20, Issue 4) by Psi Chi, the International Honor Society in Psychology


Eye on Psi Chi is a magazine designed to keep members and alumni up-to-date with all the latest information about Psi Chi’s programs, awards, and chapter activities. It features informative articles about careers, graduate school admission, chapter ideas, personal development, the various fields of psychology, and important issues related to our discipline.

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