Why did UK nurse Lucy Letby kill babies in cold blood? Devil is in details

British nurse Lucy Letby became one of the most dreadful medical serial killers in the UK after poisoning, physically assaulting, and overfeeding seven babies, which resulted in their deaths. 

The youngest victim of the serial killer nurse was only a day old. The reasons behind the 33-year-old's actions may never be fully explained, however, criminal investigators presented multiple assumptions that led her to commit the cold murders.

She was playing God

Two triplet boys who were identified as babies O and P in court were Lucy Letby's last victims. In June 2016, just after Letby returned from a vacation in Ibiza, child O passed away while child P died one day later.

Prosecutors testified at the trial that Letby was "completely out of control" at that point and "in effect playing God."

The prosecutor claimed she "played God" by injuring a baby and then being the first to inform her coworkers of the child's failing health.

"She was controlling things. She was enjoying what was going on. She was predicting things that she knew were going to happen. She, in effect, was playing God," one of the prosecutors said.

Hurting babies was enjoyment for her

Letby was twice detained before being let go. She was officially charged after her third arrest in 2020 and was kept in detention.

Police discovered hospital records and a handwritten note on which Letby had written, "I am evil, I did this." in her home.

She craved attention of a doctor

At the Countess of Chester Hospital, Letby allegedly had a covert relationship with a married doctor, according to the prosecution.

He was one of the doctors who would be contacted when babies rapidly deteriorated, which was thought to be a crucial aspect of their relationship. It was implied that she hurt them to receive his "personal attention", but Letby disagreed.

She thought she wasn't good enough

Several notes prepared by Lucy Letby were distributed to the jury members. One of the notes said, "I killed them on purpose because I'm not good enough to care for them. 

On another note, she wrote, "I will never have children or marry. I will never know what it's like to have a family."

The prosecution provided proof that Letby attacked infants using a variety of techniques, including injecting air and insulin into their bloodstreams, injecting air into their gastrointestinal tracts, forcing them to consume excessive amounts of milk or fluids, and inflicting impact-type trauma.

The jury was informed that she wanted to murder the infants while duping her coworkers into thinking there was a natural cause.

"Lucy Letby sought to deceive her colleagues and pass off the harm she caused as nothing more than a worsening of each baby's existing vulnerability. In her hands, innocuous substances like air, milk, fluids — or medication like insulin — would become lethal. She perverted her learning and weaponised her craft to inflict harm, grief, and death," said Pascale Jones of the CPS.

"Time and again, she harmed babies, in an environment which should have been safe for them and their families. Her attacks were a complete betrayal of the trust placed in her," he said.