Female Serial Killer Motivated By Trauma?

Though many find it morbid and weird, serial murder has always been fascinating to me. In most cases, it’s hard for one to wrap their head around how one individual can take the life of another – it’s even more mind-boggling to think that an individual can take the lives of multiple people. That’s why I find learning what makes these individuals tick to be so captivating. In my studies, I’ve mainly focused on male serial killers. For the main reason because there is an array of them. Not a lot of females engage in serial murder. Though, it is rare, Bartol & Bartol (2016, pg. 304) mention that there are 34 documented female serial killers. This peaked my interest and got me to shift my focus from male serial killers to female serial killers.

The motives for these killings are also different from males. Females may be motivated by material or financial gain – insurance policies, trusts, and estates (Bartol & Bartol, pg. 305). This information helped me reflect on a local female serial killer. I live in Erie, Pennsylvania – home to the famous Pizza Bomber case. If you are unfamiliar with this case, it happened back in 2003. Marjorie Diehl-Armstrong decided that she didn’t want to wait for her father to die to get his money, so she came up with a plot to kill him – only problem was that she didn’t have the money to pay the man who agreed to do it. So, she came up with an extravagant plan to rob a bank. Marjorie was able to talk a man by the name of Brian Wells into committing the robbery. The day of the robbery, a homemade bomb was strapped around the neck of Wells – which he was told wasn’t even real. Wells then went to a local bank and passed the bank teller a note demanding access codes to the vault and $250,000. The bank teller had no access to the vault and Wells walked away with less than $10,000.

Shortly after leaving, Wells was surrounded by law enforcement. He claimed that while he was out delivering pizzas a group of black men held him at gun point, put the bomb on him and forced him to rob the bank. He sat in the middle of the street yelling that the bomb was going to go off. Police stood behind cars with guns drawn while the news videoed the encounter. Just minutes before the bomb squad arrived at the scene, the bomb went off leaving a gash in his chest and killing Brian Wells.

While searching his car, police found an interesting note that instructed Wells to rob the bank of $250,000. He would then be set on a scavenger hunt to pick up more notes instructing him what to do once he got the money. Wells was under the impression that if he did what he was told to do, that he would get the keys to take the bomb off. My professor as an undergrad was the lead FBI agent on the case, and from what I can remember, there was no way Wells would have been able to complete the scavenger hunt in time before the bomb would go off.

This was not Marjorie’s first murder. Six other men in her life died in mysterious ways – five due to unnatural causes. Her murderous behavior started in 1984 when she emptied her revolver into her sleeping boyfriend. She claimed self-defense because he was abusive. Before the pizza bombing, she shot her then boyfriend in the back with a shotgun and stuffed him into a freezer because he threatened to go to police about the plan (the man who helped her was the man who turned her in for the pizza bombing case, in fear of what she might do to him). From what I can remember from class is that she was going to let his body freeze, then break it up and put it through an ice chipper to get rid of the body and evidence. Two other boyfriends also passed away, one took his own life, while another died of a skeptical overdose. Another “victim” was her only husband – he had suffered a fatal brain hemorrhage after collapsing during a stroke and hitting his head on a table.

I remember talking to my professor about her. He said that she fits into a rare category of being a violent serial female offender, that she lacked attachment which allowed her to not be influenced by her violent behavior. She had no empathy or feelings for people as humans. He also talked about how she used her mental illnesses to her advantage. Before her violent behavior, she would defraud the welfare and social security systems and beat a murder charge. She didn’t think she needed help for her illness and if someone tried to help her, she would refuse. He [my professor] was never convinced that her bipolar diagnosis was correct because he never saw a true history of depression, only manic states. She was also diagnosed in having several personality disorders – such as histrionic, anti-social, borderline and narcissistic – which my professor believed to be accurate.

I always found this case interesting, not just because it happened miles from where I live, but because Marjorie was an extremely intelligent woman. She was valedictorian in high school, had a degree in sociology and a masters in education. Merriam-Webster (2017) defines sociology as “the science of society, social institutions, and social relationships; specifically: the systematic study of the development, structure, interaction, and collective behavior of organized groups of human beings.” How could someone who lacked attachments be able to fully understand the science of society and social relationships?

When pleading her innocence in the bank robbery case, Diehl-Armstrong stated “I’m a good, decent person… I’ve got the equivalent of five college degrees, and I have a master’s degree. I’m a certified teacher. I’m a music teacher. I’m a social science teacher. I worked at those jobs. I worked with the state… I have a degree in sociology. I am not a bank robber. I don’t have to rob banks to get money. I am a certified guidance counselor. I almost have a doctorate, less dissertation. I am certified to counsel elementary and secondary schools. I am not crazed… I am not a crazy person. (Clark & Palattella, 2017, pg. 2). At the time of her trial in 1984, for the death of her abusive boyfriend, investigators found 400 pounds of butter and 700 pounds of cheese (Schapiro, 2010). She was deemed mentally incompetent SEVEN times before a judge ruled that she was fit to be tried in the case (Schapiro, 2010). In my opinion, if she constantly refused help with her mental illness, at the time of the bank robbery case she was still the crazed woman with over 1,000 pounds of rotting food in her home.

Her father, Harold Diehl, wasn’t even surprised at her plot to have him killed, saying “I wouldn’t doubt that. I heard that years ago and I believe it… Don’t forget, her mind, in my estimation, not the mind of a stable person.” (Plushnick-Masti, 2007). He also believed that if she thought it was the right thing to do, that she would kill anyone. And what adds even more interest to this case is that though her father’s estate was once valued at nearly $2 million, by the time of his natural death it was below $200,000 because of money he spent of gifts for friends – plus Marjorie was only left $2,000. Marjorie acted on an assumption that her father was wealthy, but in all actuality, she would’ve never gotten a penny after his death because as part of the will, money was to be spent on outstanding medical bills before handing out any inheritances.

So, what made Marjorie violent? Dr. William J. Ryan, a forensic psychologist, believed that Marjorie suffered from post-traumatic stress disorder, due to abuse as a child and by her boyfriends. Marjorie claimed that both of her parents inflicted mental trauma that she believes manifested itself in her psychiatric imbalance (Clark & Palattella, 2017, pg. 10). She also claimed that her father was an alcoholic and, as a child, he molested her. To Marjorie, her mother was a poor influence, claiming that her mother had a pursuit of perfection for her. She told psychiatrists and psychologists that at an early age she suffered from anorexia and was hospitalized when her weight dropped from 135 pounds to as low as 85 – she blamed her parents for her disorder stating she felt pressured by their expectations.

Could it be that these relationships triggered some past trauma in her life and resulted in violence? As I mentioned, she used her mental illness before to defraud welfare and social security. Then, she was in a relationship with a man who she claimed would beat her. That’s when she first showed her violent behavior and shot her boyfriend six times. Per Bartol & Bartol (2016, pg. 233) PTSD has been used to excuse or mitigate criminal responsibility in cases involving battered women who maintain that they have battered woman syndrome. In another murder, it was argued that she shot and killed her boyfriend to keep him from going to police about the bomb and robbery plot, but Marjorie insisted it was a crime of passion that was provoked by his abuse. She pleaded guilty but mentally ill to his murder and received a 7-20-year sentence.

Was Marjorie’s trauma the root of her violence or was her mental illness the driving force?

Marjorie passed away this year from cancer and remains a mystery.


Bartol, C. R., & Bartol, A. M. (2016). Criminal behavior: A psychological approach. 11th Edition. Boston: Pearson.

Clark, J., & Palattella, E. (2017). Mania and Marjorie Diehl-Armstrong: inside the mind of a female serial killer. Lanham, MD: Rowman & Littlefield.

Merriam-Webster. (2017). Sociology. Retrieved from https://www.merriam-webster.com/dictionary/sociology

Plushnick-Masti, R. (2007). Robbery-plot suspect’s father not surprised. Retrieved from http://www.philly.com/philly/news/local/20070713_Suspects_father_not_surprised.html

Schapiro, R. (2010). The incredible true story of the collar bomb heist. Retrieved from https://www.wired.com/2010/12/ff_collarbomb/

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