How a woman’s brain donation helped convict her husband of double murder

Vanessa Easton remembers Diane Stewart, her neighbor of many years, as a smiling, caring and outgoing school secretary.

“She was a lovely person who anyone could strike up a conversation with,” says Vanessa, who has lived across the street from the Stewarts — Diane, her husband Ian and their two children — in Cambridgeshire, eastern England, since 1993.

They used to take care of each other’s cats when they went on vacation and enjoyed the neighborhood fireworks together.

Pthey were a perfect and happy familyVanessa describes the Stewarts. “It was so obvious how much they loved their children! Diane was full of love for them.”

But on June 25, 2010 everything changed.

Stewart said he returned home from shopping to find his wife of 47 years, who had been doing laundry, lying on the floor. Shortly after, she was declared dead.

An investigation that same year concluded that the woman had suffered a sudden death from epilepsy (SUDEP), which kills about 600 people each year.

Diane and Ian Stewart at one of the neighborhood fireworks shows. (Photo: COURTESY IMAGE)

Although Diane had not suffered an epileptic seizure in 18 years, her death did not raise any suspicions.

But they did come up with death six years later of a second woman: Stewart’s fiancée, the author of children’s books Helen Bailey.

Stewart had secretly drugged and suffocated Helen to inherit her fortune of more than $5 million, and dumped her body in a cesspool below her home in Royston, Hertfordshire, in southern England.

The suspicions

Convicted of Helen’s murder in 2017, police turned their attention to Diane’s death.

The investigation faced several major obstacles.

Not only had Diane’s body been cremated, but also complete toxicological tests were not performed during the exam post-mortem from 2010.

The only analysis was on an antiepileptic drug.

Ian Stewart and Helen Bailey
Ian Stewart drugged and suffocated Helen Bailey. (Photo: SOUTH BEDS NEWS AGENCY)

It was Stewart who authorized the cremation. During his testimony at trial, prosecutors accused him of doing “so that there was very little that could turn against him”.

However, the detectives followed a rather unusual path.

The brain as evidence

Diane had donated her brain to medical research, something Stewart consented to. Without that consent, this vital source of evidence would have been destroyed.

Superintendent Jerome Kent, of the Bedfordshire, Cambridgeshire and Hertfordshire Major Crimes Unit, says they discovered the brain was kept in hospital.

Superintendent Jerome Kent
Superintendent Jerome Kent says they couldn’t have convicted Ian Stewart without his wife’s brain. (Photo: KATE BRADBROOK/BBC)

He explains that being able to access Diane’s brain was “absolutely crucial” and that without it “a conviction could not have been guaranteed.”

“It was also important to remember that if she had died of natural causes, we wanted to be able to tell the family that their concerns and suspicions were unfounded.”

According to neuropathologist Colin Smith of the University of Edinburgh, Scotland, the use of stored brain tissue as part of a police investigation is extremely unusual.

“I’ve never been in that situation before,” he tells the BBC.

But how did science help catch the killer?

Restricted breathing

A team of scientists and pathologists were recruited to re-examine Diane’s brain tissue.

Safa al Sarraj, a neuropathologist at King’s College Hospital in London, told the jury that he found “changes in the brain consisting of early ischemia,” which he defined as damage to cells due to lack of oxygen and blood flow.

Diana Stewart
Diane Stewart was drowned by her husband, analysis of her brain tissue revealed. (Photo: COURTESY IMAGE)

The scientist said that no trace of ischemia would be expected to be found in “a healthy breathing human being”.

He also revealed that it can be found when a person dies after suffering a “restricted” breathing for “more than 30 minutes”.

Another expert witness, neuropathologist Kieren Allinson, found “no evidence of a recent seizure,” though he added that didn’t mean it wasn’t a death from epilepsy.

Home Office pathologist Nat Cary, who gave evidence in 2017 at the Helen Bailey murder trial, said there was a possibility Diane’s breathing had been interfered with by the use of some kind of drug.

At the time of Diane’s death, Stewart called the emergency number.

“My wife had a seizure. She is in the garden “, he told the operator. When asked if the woman was breathing, he replied: “No, I don’t think so, no.”

Their neighbor Victor Nickson helped guide air ambulance paramedics to the Stewarts’ home.

The Stewarts lived on a farm in England.

“I saw them thumb down and shake their heads in response to the paramedics’ questions. CPR (cardiopulmonary resuscitation) stopped,” she said.

“One put his arms around Stewart, who was showing signs of stress and worry.

At that time, another neighbor, Vanessa, a nurse, came home and saw Diane’s body: “I remember thinking, ‘Thank God there’s no blood,’” she says.

He also notes that Diane’s death was “totally unexpected”and that although he suffered from epilepsy “it was well controlled.”

No real motive for Diane’s murder has yet become apparent.

Vanessa can’t find the answers.

vanessa easton
Vanessa Easton recalled that there was no blood near Diane’s body when she saw her dead in her front yard. (Photo: KATE BRADBROOK/BBC)

“Ian had it all: a loving family, a wonderful life. His wife was a loving woman and a lovely person. Why did he throw it all away? Why did you do that? It’s something that doesn’t fit and I can’t understand, ”he says of Diane’s murder.

Vanessa’s husband, Paul, said of Stewart that he found it “pretty difficult” to relate to him. “She would get very close when she spoke, invading your personal space,” he added, though “I never hadandra imagined that would be able to kill tosomeone”.

Six years later, Stewart would end the life of his new partner.

Helen’s murder

After Diane’s death, Stewart moved on with her life. He bought a sports car before beginning a relationship with Helen Bailey.

In April 2016, Stewart reported her missing.

Helen Bailey
Helen Bailey’s body was found three months after she was reported missing. (Photo: SBNA)

Three months later, Helen’s body was found in a “smelly” cesspool next to the corpse of her dachshund, Boris.

Helen had written more than 20 books, including the popular series Electra Brown.

Her husband, John Sinfield, died in 2011 while on vacation in Barbados, drowning at sea after being swept away by the current.

She and Stewart met through a dueling website, they bought a house together and planned to get married.

Helen Bailey and Ian Stewart
In 2017, a jury found Stewart guilty of killing her partner, children’s book author Helen Bailey. (Photo: SWNS)

Margaret Holson, who had become close to Helen in the months before her murder, says that what angers her most “is the thought that if more had been done to find out what happened to Diane, my friend Helen would still be here.”

No we had that information or evidence at the time.”answers Superintendent Kent.

“At the time of Diane’s death there was nothing to suggest that Ian Stewart had been responsible or that she had died at his hands,” it adds.

“He would have gotten away with the Diane Stewart murder if it hadn’t been for the Helen Bailey investigation.

“I hope there aren’t too many more unidentified murders… but it is, of course, a possibility.”

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