How did a 'nerdy weird' IT worker use fentanyl to murder couple?

The case of an IT worker who used fentanyl to fatally poison his family friends will be the focus of a two-part documentary.

Stephen Baxter, 61, and his 64-year-old wife Carol were found dead at their home in West Mersea, Essex, in April 2023.

They were manipulated by Luke D'Wit, 38, who laced their medication with the opioid painkiller while using fake identities to control their lives.

Essex Police said unmasking the killer, described as "nerdy weird" by the couple's daughter, Ellena Baxter, was one of its most complex ever investigations.

He was jailed for life with a minimum tariff of 37 years at Chelmsford Crown Court in March 2024.

But who is Luke D'Wit and how did he carry out the murders?

With family ties going back generations on the insular island of Mersea, Luke D'Wit was seen as a pillar of the community.

The computer science graduate lived with his mother in a small semi-detached home in Churchfields, a stone's throw from the seafront.

Locals knew him as a quiet man who volunteered at a soup kitchen and helped to organise the town carnival.

It was why many refused to believe he orchestrated the murders of two millionaires in the desirable town.

But detectives uncovered D'Wit, who met the Baxters sometime around 2012 or 2013, was not the upstanding member of society he had disguised himself as.

He was introduced to the couple through his work as a freelance web designer, and helped to create a website for Mrs Baxter's shower mat business, Cazsplash.

The relationship evolved when D'Wit started keeping Mrs Baxter company on walks and at the gym. He also helped her take medication and performed odd jobs.

During this period, he faked a cancer diagnosis to gain the family's sympathy, his trial heard.

It got to the point where "he was always there" with the Baxters, family friend Kate Dawson told the BBC.

When Ellena found her parents dead in their armchairs on Easter Sunday 2023, she immediately suspected carbon monoxide poisoning was to blame.

It was not until post-mortem examinations took place that fentanyl and promethazine were found to be a significant factor in both deaths.

A falsified will inside the couple's home in Victory Road, which named D'Wit as director of Cazsplash, led detectives to the killer.

Upon his arrest, they began to uncover the extreme lengths D'Wit explored to control the Baxters.

His manipulation mainly targeted Carol Baxter, who suffered from the thyroid condition Hashimoto's disease.

He created a fake doctor, called Andrea Bowden, who gave Mrs Baxter advice about her condition and put her in touch with a wide network of pretend patients.

Mrs Baxter desperately wanted solidarity, and on one occasion, the couple drove three hours to a hotel to meet one of the false identities who cancelled on them at the last minute.

Police seized 80 electronic devices at D'Wit's house, some of which had been used to create more than 20 false personas used for his manipulation.

Analysis of the devices found he was offering advice "with no clinical basis" while posing as Dr Bowden, prosecutors told the trial.

This advice included taking smoothies that were rich in health benefits made by D'Wit, who Dr Bowden praised as a good friend.

Instead, they were cocktails of drugs and potions which made her far more unwell than she already was.

Ellena told jurors D'Wit used Dr Bowden to enforce "this set of rules we had to follow" for her mother's treatment.

But the dementia-like symptoms and deterioration Mrs Baxter was suffering from were not typical of Hashimoto's.

They were the effects of her being slowly poisoned by D'Wit, who ensured Mrs Baxter kept him updated on her decline via video messages she sent to Dr Bowden.

The police investigation uncovered an email sent by D'Wit to the couple on the morning of their deaths, detailing a "liver cleanse recipe" they should follow.

It explained how the fatal dose of fentanyl had been administered into their bodies.

D'Wit then watched them die between Good Friday and Easter Sunday in a video stream he set up from a phone hidden in their property.

Sentencing D'Wit, the Honourable Mr Justice Lavender said he was motivated by a "desire to control others".

"Deciding whether another person lives or dies is the ultimate form of control," he said.

D'Wit used fentanyl patches prescribed to his late father, Vernon, to carry out the murders.

The BBC revealed in July that detectives were also reviewing the deaths of D'Wit's father and grandfather in case he had killed them and avoided detection.

Both opened and unopened patches were found in a bag at his home by police, as well as metal tacks.

The same tacks were found during a scan of Mrs Baxter's stomach when she was alive.

"Your relationship with the Baxters and Carol Baxter's illness had led the Baxters to trust you to prepare supposed health drinks for her for some time," the judge said.

"This is what gave you the opportunity to do what you did."

Mr Justice Lavender criticised D'Wit's "amateurish" attempt to create a will, which named him as their "dear friend".

However, it was suggested the will was more of an afterthought rather than the ultimate motivation.

The judge said D'Wit maintained his grip over the family in the three months between the murders and his arrest by targeting Ellena.

He did so by taking her out for dinner on the night he killed the Baxters, as well as arranging the funeral and using one of the false identities to console her.

In a final attempt at manipulation, he used a wheelchair throughout the trial in what prosecutors said was an effort to gain the jury's sympathy.

Addressing the killer, the judge concluded: "What you did was cruel and senseless."

Essex Millionaire Murders airs on ITV1 at 9pm on both Monday and Tuesday.

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