Access and Attention: Why serial killers like Lucy Letby often work in healthcare

British nurse Lucy Letby was sentenced to life in prison last week for killing seven children in her care and attempting to kill six others.

As a forensic criminologist, many people have asked me why a medical professional would kill their own patients.

Although they are very rare, serial killer healthcare workers often share common traits and target a specific and very vulnerable group of victims.

Although limited research has been done on serial killer doctors, there are some trends among serial killers that can help us understand the role of the profession in the act of serial killing.

Foster killers

A serial killer is usually defined as someone who kills at least three people in a series, but in any single event there need not be a cooling-off period between the killings. While the public is generally fascinated by these predators, serial killings are a rare occurrence, accounting for less than 1% of all homicides that occur in the United States each year.

Serial killers come from all walks of life and not all are dysfunctional loners, many are married or in stable relationships.

A 2014 research paper found that serial killers can be understood through several subtypes, including: those who kill for sexually sadistic pleasure; professional killers motivated by the money and power that comes with killing; and, as for Letby, the killers in custody.

Custody killers are often healthcare workers who kill helpless people or employees in their care.

The author of the document writes of the killers in custody:

The most common examples include angels of death cases involving nurses in hospitals or nursing homes covertly killing sick or elderly patients, usually from asphyxiation or a drug overdose. This group is likely to contain the largest number of female serial killers.

The manner of the murder is likely related to their profession. Healthcare workers have access to drugs unavailable to others, as well as the knowledge to cover up their crimes more effectively.

A research team studied 64 female serial killers in the United States between 1821 and 2008 and found that nearly 40% of them worked in the healthcare sector.

But the question remains: why do they kill? Looking specifically at women, the 2014 research paper suggests that, unlike men who kill out of predatory lust and/or compulsive rage, female serial killers are typically driven by an histrionic attention-seeking or financial gain.

Letby and the health killers

Another research paper specifically studied the characteristics of 16 convicted medical serial killers, who the authors defined as nurses convicted of at least two homicides, committed in a hospital setting.

While this was a small sample size, they found that 56% were female and the average age of those accused was 36.

About 44% killed between five and nine victims before being caught, and 75% were killed in just one location. Insulin was the most common method of killing, followed by muscle relaxant.

Read more: Women can be psychopaths too, in more subtle but equally dangerous ways

Letby satisfies many of these characteristics. She is a woman, she is 33 years old and has killed seven children. She has killed, as far as we currently know, in only one location and used insulin to kill some of her victims.

A 2007 book, Inside the Minds of Healthcare Serial Killers: Why They Kill, provides a checklist of 22 warning signs for this group of killers, including:

• secret/difficult personal relationships

• history of depression or mental instability

• higher fatality incidents during the shift

• make colleagues anxious or suspicious

• crave attention.

Letby certainly made her colleagues suspicious, who denounced her in the years leading up to her arrest. There were more infant deaths during her shifts than any other member of staff, and that’s how she got caught.

A criminal psychologist has suggested that part of the rationale behind the murders may have been to attract the attention of a male colleague, whom prosecutors alleged she had a crush on. This would fit with research suggesting that attention seeking is a motive for female serial killers more generally.

More Notorious Healthcare Killers

Harold Shipman was an English general practitioner who is considered one of the most prolific serial killers in modern history.

He was convicted of the murders of 15 of his patients in 2000 but is suspected in the deaths of around 250 people.

Most of his victims were elderly women in good health. He killed many by injecting them with lethal doses of diamorphine (medical grade heroin), after which he forged their death certificates to indicate that they had died of ill health.

Suspicions were raised because the number of his deceased patients was very high, as was the number of cremation orders that his colleagues had to countersign.

Given that the patients he killed were largely in good health, misguided altruism cannot explain his crimes.

Niels Hgel, a German nurse, is another example. In 2019, Hgel was found guilty of using lethal injections to kill 85 of his patients, some of whom he attempted to resuscitate to show off to his colleagues.

Doctors who kill are rare

The reason why the Letby case (like Shipman’s before it) is garnering such significant public interest and horror is because we view physicians as trusted professionals.

We place our lives in their hands, and cases like these cause considerable fear when it is discovered that someone has violated that trust in such a radical way.

But it’s important to recognize that they hold such interest precisely because they are so rare.

While doctors who become serial killers are incredibly prolific, we shouldn’t fear unnecessarily for ourselves or our loved ones.

If you are concerned about a medical professional, you should report it to the appropriate authority. High-profile cases like Letby’s have shown that these individuals can be caught and their behavior patterns identified, and in this way we can protect the most vulnerable among us.