Man twice found guilty of same murder has second conviction quashed

A man twice found guilty of a woman’s murder almost 30 years ago has had his conviction quashed for a second time at the Court of Appeal.

Justin Plummer was jailed in 1998 after a jury found he had fatally attacked Janice Cartwright-Gilbert at the building site of her future home near Wilden in Bedfordshire the previous year.

Ms Cartwright-Gilbert, who was 38, was stabbed with a knife and scissors before her body was set alight in a caravan next to the building site.

Plummer, who was 24 at the time of Ms Cartwright-Gilbert’s death, had his first murder conviction quashed by the Court of Appeal in 2021 but was convicted again following a retrial at Aylesbury Crown Court in 2023 and sentenced to life with a minimum term of 16 years.

His barristers challenged his second conviction at the Court of Appeal earlier this month, claiming that the trial judge was wrong to allow hearsay evidence to be presented to the jury from a police informant, Christopher Dunne.

Dunne had shared a cell with Plummer before his first conviction and claimed he had confessed to the murder, but the "cell confession" was not used in the first trial, and Dunne died in 1999.

The Crown Prosecution Service (CPS) opposed the appeal, with its barristers stating that "there remains a substantial case" against Plummer.

In a ruling on Wednesday, three senior judges quashed Plummer’s second conviction, stating that Dunne’s claims "should have been withdrawn from the jury."

Lord Justice Edis, sitting with Mrs Justice McGowan and Judge Nigel Lickley KC, said: "Dunne was a criminal and paid police informant who was in the habit of passing information to the police about other criminals for his own benefit."

He continued: "The circumstances of the suggested confession to murder and the reliability of the informant are such as to raise concerns about it."

He added: "He gave no detail of the murder which could support its reliability."

Ms Cartwright-Gilbert suffered a broken nose when she was fatally attacked before being stamped on, stabbed in the heart, lungs and neck and then set on fire, with her two dogs also killed in the blaze.

After being found guilty of murder at St Albans Crown Court in December 1998, Plummer lost an appeal in 1999 but had his conviction quashed in 2021 after it was referred to the Court of Appeal by the Criminal Cases Review Commission due to concerns over expert evidence.

He was then found guilty of murder again two years later, after prosecutors told a jury that Plummer had killed Ms Cartwright-Gilbert in a burglary gone wrong, and used Dunne’s evidence of the alleged confession.

Plummer admitted to burglary, but denied murder and that he had ever given a confession.

At a hearing on July 15, Katy Thorne KC, for Plummer, said that Dunne’s evidence "should never have been admitted" and that the trial judge "failed to properly consider" that the evidence had "inherent potential unreliability."

She also said that records indicated that a payment had been made to Dunne at the time he provided evidence to the police, but "there has never been any explanation given by anyone" for what it was for.

In a 48-page ruling, Lord Justice Edis said that Dunne and Plummer shared a cell together for around three weeks in June 1997, before Plummer’s first conviction.

Dunne, who had been an informant since 1996, did not ask to speak to police about the alleged confession until August 1997, and gave a differing account that December.

He said that there were "discrepancies and matters that cannot in fact be correct" in Dunne’s accounts, which also did not provide "any account of the killing."

The judge also said that while Dunne’s evidence was "decisive" at trial, it was "unconvincing."

He continued that the retrial "should have been stopped" after the jury had heard the evidence, and that the judge’s "failure to do that clearly therefore renders the conviction unsafe."

Following the ruling, a CPS spokesperson said: "Today, our thoughts remain with the family and loved ones of Janice Cartwright-Gilbert, who lost her life in 1997 to a terrible crime.

"In both the original trial and retrial, the CPS prosecution assessed the evidence fairly and independently and were satisfied it showed a realistic prospect of conviction.

"Having carefully considered the judgement, it is not possible for the prosecution to seek a further retrial as the remaining evidence, without the cell confession, would not provide a realistic prospect of conviction."