Female serial killers typically motivated by money, chilling research reveals

‘The people familiar to her are at most risk, especially children, the ill and the elderly.’

UNIVERSITY PARK, Pa. — The motive for male serial killers is often sex, whereas female mass murderers tend to go after money, according to a new study. Research specifically into the gender differences between serial killers shows women are most likely to kill for financial gain, usually targeting someone familiar to them.

A researcher and author at Penn State University notes that women tend to kill more vulnerable people, including the elderly, the sick, or children, and are more than twice as likely to kill their spouse or partner. Meanwhile, men’s motives often differ, usually killing for sexual gain. They’re more likely to target strangers and stalk their victims.

Women are usually clinical with their method of murder, as they aim to make the death look as natural as possible, killing by poisoning or asphyxiation. Men are less likely to use poison, but often stick to asphyxiation, killing their victims by depriving them of oxygen.

“The people familiar to her are at most risk, especially children, the ill and the elderly. Most likely she murders via poisoning or asphyxiation, and those methods would mimic natural death to people who aren’t really suspecting her,” says Dr. Marissa Harrison, an associate professor of psychology at Penn State, in a university release.

Harrison, the author of the new book, “Just as Deadly: The Psychology of Female Serial Killers,” says women who commit these crimes often have been married at least once, while men tend to be single at the time of their first crime. Education also plays a role. Women serial killers are more likely to have a higher level of education, while male murderers usually have a high school education or less. Women serial killers often have been to college or university, with almost 40 percent being nurses or health care workers.

“She’s probably white, married at least once, maybe multiple times. She’s probably in her 20s or 30s, likely middle class, a Christian, displays at least average intelligence and has average or above average attractiveness,” Dr. Harrison continues.

“She is probably employed legally, perhaps in health care or a related field. In fact, we found that 39% of female serial killers were nurses or health care workers. They might have a history of abuse or a recent crisis. And at least one murder will occur in a suburban area.”

Male and female serial do have some traits in common

There are similarities between the genders, including mental illness and a history of abuse or trauma.

“My team’s research shows that for female and male serial killers, there is a good chance that mental illness is involved,” Dr. Harrison reports.

“For males, it’s highly likely; for females, our research showed about 40% demonstrated evidence of mental illness. If instances of mental illness and child abuse continually appear in the histories of these women, maybe mental illness awareness and treatment could prevent some future deaths.”

Martha Patty Cannon is an example of this. She killed men, women, and children and kidnapped free people and sold them into slavery in 19th Century America. Her abuse of children was shocking, as she used to beat children to death with logs. One time, she threw a child into a fire just because they sneezed near her. Her history shows that she was raped by her father during the late 1700s to early 1800s. Her father was hanged as a result.

“Think about what a taboo subject that was back then, and that people knew this happened and they hanged the father. It must have been known that he abused her, and the abuse must have been terrible,” the author explains.

Among these brutal women is Jolly Jane Toppan. A nurse from Boston in the late 1800s, she was found to have killed at least 30 people but admitted to police that she had killed closer to 100.

Another is Belle Gunness, a farmer from Indiana. When digging up her farm, the authorities found the remains of around 100 people.

“The FBI did not recognize female serial killers until the 1990s,” Dr. Harrison says. “But there are well-known women who murdered far more victims than men did.”

Marybeth Tinning is thought to have killed eight of her nine children born between the 1960s and 1980s. Her case demonstrates the risk of the myth that men are more likely to murder than women.

“What shocked me was, OK, now she has three dead children. OK, here’s the fourth. OK, here’s the fifth presented to a local hospital,” the author notes. “Some of the media reported that people were calling a hotline saying, aren’t you going to do something?”

“People noticed what was going on, the shock was how long it took the authorities to act. Authorities think she probably had ‘Munchausen syndrome by proxy,’ that she killed the babies for attention.”

The media plays a role in the myths created around serial killers

Women murderers usually are given a nickname which shows their gender, like Tiger Woman. Men, however, are referred to more by their crimes, such as Jack the Ripper. Movies, books, and podcasts also influence this as they popularize stories of male serial killers like Ted Bundy and Jeffrey Dahmer. The new study shows that women are also capable of committing such heinous crimes.

“There’s so much rumor and gossip about serial murderers, but the field lacks information on female serial killers,” Harrison concludes. “I’m a psychological scientist, a data-wrangler. My book presents a psychological science approach to understanding the minds of female serial killers.”

“Women commit murder, and they get away with it.”

South West News Service writer Alice Clifford contributed to this report.