Fentanyl murderer who poisoned married couple may have killed his own father who was found slumped in a chair and avoided detection, police fear - as review is launched

A convicted murderer who poisoned a married couple with fentanyl may have killed his own father and avoided detection, police fear.

Luke D'Wit, 34, was jailed in March for life with a minimum of 37 years after he used the opioid painkiller to fatally poison Stephen and Carol Baxter in West Mersea, Essex.

But in a bombshell update, detectives are now reviewing whether the murderer was responsible for the death of his father, Vernon, who had been prescribed fentanyl before he was found slumped in a chair at the family home in 2021.

Essex Police said officers 'will not hesitate to act' if they come across fresh evidence, the BBC reports.

Detectives are also said to be investigating the death of D'Wit's grandfather as part of their review.

MailOnline has contacted Essex Police for comment. 

Det Supt Rob Kirby previously told the BBC he had 'absolutely no doubt' D'Wit would have carried out more subtle murders had he not been locked up.

He also could not rule out whether the murderer had targeted other victims before he was convicted.

Det Supt Kirby said D'Wit was 'one of the most dangerous men' he had dealt with in his career.

D'Wit's father was found dead in a chair at home in West Mersea in 2021.

Married couple Mr Baxter, 61, and Mrs Baxter, 64, were also discovered in their armchairs - by their daughter Ellie - at their home in West Mersea on Easter Sunday 2023.

Chelmsford Crown Court heard how D'Wit had extracted the painkiller from patches originally prescribed to his father and retained the drug 'in abundance'.

Police found a haul of the opioid painkiller in a backpack at the home D'Wit shared with his mother in Churchfields, West Mersea. 

'Up to the conviction and sentence of Luke D'Wit, our determined focus has been securing justice in relation to the murders of Carol and Stephen,' the Essex police spokesman said.

'As with any investigation of this magnitude, everything we have uncovered is being reviewed and should anything suggest this has been the case we will not hesitate to act.'

D'Wit befriended and worked for the Baxters before changing their will to make him a director of their shower mat firm.

He then created a series of fake online personas to manipulate them before he killed them.

He had pretended to be a doctor from Florida and members of a fake support group for the thyroid condition Hashimoto's, which Mrs Baxter suffered from.

D'Wit denied their murders but was found guilty by unanimous verdicts at Chelmsford Crown Court on March 22 following a trial that lasted more than a month.

He was sentenced to life with a minimum of 37 years by judge Mr Justice Nicholas Lavender, who said D'Wit 'ended their lives and brought grief and misery to the lives of others'.

Mr Justice Lavender did not accept the prosecution's assertion that D'Wit's behaviour was sadistic, because his victims were sedated when they died.

But he added: 'I consider it was possible that what motivated you was the desire to exert control on others… deciding whether someone lives or dies is the ultimate form of control.'

The judge also told D'Wit: 'It's distinctly possible what motivated you was a desire to control others.'

The defendant, who wore a patterned blue short-sleeved shirt, appeared to show no reaction as he sat in a wheelchair in the secure dock.

The judge said he was sure that D'Wit 'extracted the fentanyl from patches which had been originally prescribed for your father, who died in 2021'.

He said these were crushed into a powder and given to the Baxters in a drink, which they took as they trusted D'Wit to prepare 'supposed health drinks'.

Det Sup Kirby said outside court: 'In all my years of policing, Luke D'Wit is one of the most dangerous men I have ever come across.

'I have absolutely no doubt in my mind had he not been caught he would have gone on to kill further people.'

He said that D'Wit 'disgracefully ... based his defence on collusion between himself and Stephen Baxter'.

'Stephen is tragically not here to defend himself but from everything we knew about him we know this could never have been the case,' said Mr Kirby, of the Kent and Essex Serious Crime Directorate.

'Thankfully, today the jury have seen through D'Wit's fantasies and delivered guilty verdicts.'