Was Lucy Letby an unlikely serial killer? To most people, yes – but not psychologists | Marissa Harrison

Our research into women who kill acts as a reminder to challenge our preconceived notions of others

Dr Marissa Harrison is a professor of psychology and author of Just as Deadly: The Psychology of Female Serial Killers

The crimes of the convicted serial killer Lucy Letby have rattled the UK and the world. One can think of nothing worse: babies who were grievously ill, killed or injured by a woman who was meant to care for them. Why was Letby able to kill so many young victims? Why wasn’t she recognised as a murderer sooner?

Some are saying that Letby’s case is a “one-off”, and is thus difficult to process or learn from. While serial murder is rare, to those of us in the field of serial homicide research, the crimes and victims of Letby are less surprising. In many ways, Letby fits the profile for the “typical” female serial killer (FSK) that my team and I compiled for The Journal of Forensic Psychiatry & Psychology in 2015. By analysing cases in the US, we found that nearly 40% of female serial killers are nurses, nurses’ aides or other healthcare workers.

Dr Marissa Harrison is a professor of psychology at Penn State Harrisburg. She is the author of several scientific articles and a book on female serial killers, Just as Deadly: The Psychology of Female Serial Killers. She is a member of the Atypical Homicide Research Group network

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