The Chilling Case of Lucy Letby: How a Trusted Nurse Became Britain’s Most Notorious Child Killer

Content warning: This story contains graphic descriptions of violence that may be disturbing to some readers.
“I have always wanted to work with children.”
It’s a phrase you might expect from a nurse dedicated to caring for babies and young children. But when Lucy Letby uttered these words during her trial, they took on a terrifying meaning. She stood accused of murdering seven infants and attempting to murder six others—a betrayal of trust so unthinkable it shocked the nation.
At the time of her arrest, Letby was a neonatal nurse, a profession, according to clinical and forensic psychologist Dr. Ahona Guha, “where people are revered and trusted without question.” She was entrusted with the most fragile lives in the Countess of Chester Hospital’s neonatal unit. Instead, she exploited that trust, taking the lives of helpless newborns before they even had a chance to begin.
Dr. Guha told Mamamia that Letby’s attraction to working with babies—and what they represented to her—was “an intriguing question,” one that continues to baffle experts. “It’s so rare to see babies as victims,” she noted. “What’s truly unsettling about Letby is how utterly ordinary she appeared.” Dr. Guha added, “She didn’t fit the usual profile—no history of poverty, abuse, trauma, or criminal behavior. She seemed studiously normal.”

From Promising Graduate to Britain’s Most Prolific Child Killer
Letby was the first in her family to attend university, studying nursing at the University of Chester. Nearly all her clinical placements were at the Countess of Chester Hospital, either in the children’s ward or the neonatal unit.
In January 2012, she began working full-time at the hospital, later qualifying in 2015 to care for intensive care infants. She told the court she spent most of her time with the “sickest babies” on the unit, estimating she had cared for hundreds of newborns in 2015 and 2016.
When an alarming surge in infant deaths and unexplained collapses occurred in the neonatal unit, an investigation was launched. It led police straight to Letby’s door.
Throughout the inquiry, detectives interviewed doctors, nurses, and administrators, while scouring hospital records. One critical document revealed that Letby was on duty every time a baby collapsed or died.
In July 2018, at just 28 years old, she was arrested at her home and led away in handcuffs. After two more arrests, she was formally charged in November 2020.
Letby vehemently denied all 22 charges—seven counts of murder and attempted murders of 10 others.

The Shocking Revelations of the Lucy Letby Trial
Despite her insistence of innocence, police discovered a handwritten note in her bedroom, scrawled with the words: “I AM EVIL. I DID THIS!”
Letby’s defense attorney dismissed the note as “the desperate outpouring of a young woman in fear and despair.” However, prosecutors painted a different picture—that of a cold, calculating killer who “played God”, falsified medical records, manipulated colleagues, and even connected with grieving parents.
The court heard that Letby had sent a sympathy card to the parents of a baby she was accused of killing after four attempts. She had also spent time with another grieving family, photographing their deceased child.
Policing Academic Associate Professor Dr. Michael Kennedy drew parallels to the Kathleen Folbigg case, where diary entries were key evidence in her conviction for murdering her four children. “Experts ruled out coincidence,” he noted. “The same applied in Letby’s case.”
However, DNA evidence later disproved natural causes in the Folbigg case, leading to her release. In Letby’s nine-month trial, jurors were shown images of her home, including a childlike bedroom decorated with fairy lights, stuffed animals, and motivational posters—a stark contrast to the horrors she was accused of.
After 110 hours of deliberation, the jury convicted her of seven murders and six attempted murders. In August 2023, she was sentenced to 14 whole-life terms—ensuring she will never be free.
Almost a year later, in July 2024, Letby was convicted again—this time for the attempted murder of another newborn—and given a 15th whole-life term.
Once more, she proclaimed her innocence, telling the judge, “I’m innocent.”
She has since lost two appeals—one in May 2024 for the original convictions, and another in October 2024 for the attempted murder of a baby girl.
In February 2025, Letby filed a “last resort” appeal with the Criminal Cases Review Commission (CCRC), a body that reinvestigates potential miscarriages of justice. A review could take over a year.
Meanwhile, police are examining 4,000 neonatal admissions from hospitals where Letby worked or trained.
In January 2026, the Crown Prosecution Service (CPS) announced no new charges would be brought against her for additional baby deaths and collapses, stating that “the evidential test was not met in any of those cases.”
A public inquiry, led by Lady Justice Thirlwall, is ongoing, with the final report expected after Easter 2026.

The Unanswered Question: Why Did She Do It?
Determining a motive for such horrific crimes has proven difficult, especially since Letby continues to deny guilt.
Detective Superintendent Paul Hughes of Cheshire Police suggested Letby “clearly loved the attention.” “But if we’re searching for why she did this,” he added, “then, using her own words, ‘she is evil, and she did this.’”
Dr. Guha believes the truth is more complex. “Female serial killers are rare, and those who do exist often act with partners or for financial gain. Without those factors, we’re left examining her personality. That’s where the answers—or lack of them—may lie.”
Associate Professor Kennedy agreed that evil is the least likely explanation. “Mental health plays a significant role in these cases,” he explained. “That doesn’t mean offenders don’t understand their actions are wrong or shouldn’t be incarcerated. For Letby, Munchausen’s syndrome might best explain her behavior—a cry for attention, a need to be valued.”
Dr. Guha speculated that Letby may have narcissistic or psychopathic traits. “She presents as much younger and less mature than her age,” she observed. “What does that say about her ability to connect, seek attention, and navigate the world as an adult? From a personality standpoint, she likely had narcissistic or psychopathic tendencies. It’s difficult to harm infants without some emotional detachment.”

How Did She Evade Detection for So Long?
Beyond Letby’s manipulation of her trusted role, both Dr. Guha and Associate Professor Kennedy believe systemic failures enabled her to continue killing without consequence.
The court heard that doctors had raised concerns about Letby as early as 2015. “This elevates toxic workplace dynamics to another level,” Dr. Guha stated. “It highlights the danger when concerns are ignored. Once red flags appeared, management seemed to protect her.”
Kennedy called it a “fascinating case of workplace dynamics.” “Red flags were evident early on, but she knew how to navigate the system. Another factor was senior management prioritizing the hospital’s reputation over patient safety. Despite years of concerns, they failed to alert authorities—likely resulting in preventable deaths.”

Is Rehabilitation Possible?
“I wouldn’t want Letby anywhere near vulnerable individuals,” Dr. Guha declared. “Regarding mental health, it doesn’t typically cause this level of offending—unless she was psychotic before each murder. Many people struggle with mental health, but most don’t kill babies. In forensics, we seek causal links, not just correlations.”
Kennedy acknowledged that rehabilitation is possible, but not always successful. “Sadly, some individuals must remain incarcerated.”