Episode 8 of The Overturn – Justin Plummer: 28 years in prison for a crime I didn’t commit

Listen to the full episode below, or via Spotify.

In 1998, Justin Plummer was convicted for the brutal murder of Janice Cartwright-Gilbert. She had been living with her partner in rural Bedfordshire, in a caravan while they renovated a property. She was found having been stabbed multiple times, strangled with an electric flex, and her caravan was torched. Justin Plummer was a prolific burglar in the area, but always protested his innocence of this murder. On being remanded in prison he flooded his cell in protest. He then slept on the floor of his cell every night that he was in prison for the killing – for 28 years.

In July 2025, it took less than eight minutes for the Court of Appeal to overturn his conviction as part of its annual deck-clearing before the end of the legal year ahead of the summer break.

A prolific burglar, Plummer had been in custody when he was first questioned about the killing. Whilst he pleaded guilty to 24 convictions for theft and burglary in the four-month run-up to the murder, he denied any involvement with the killing. His lawyer, Katy Thorne KC, describes in this episode that although he was constantly stealing, he never confronted the people he was stealing from – and there was no evidence that Cartright-Gilbert had been killed during the course of a robbery.

There was no witness evidence or DNA that put Plummer at the crime scene. The only evidence that was used to convict him was the testimony of an expert witness who said his Nike trainers were an exact match with a footprint on the dead woman’s face. This is despite the fact that these trainers, supposedly worn during a savage murder, had none of the victims blood on them. He unsuccessfully appealed in 2000, then launched a failed application to the Criminal Cases Review Commission (CCRC). Seventeen years later, a second application was made to the CCRC which led to the conviction being overturned in 2021 after the expert evidence matching his trainers to the footprint was completely discredited. The expert witness who has testified to this was a dentist, not a forensic scientist, and his methodology had since been completely trashed.

To the surprise of Mr Plummer’s legal team, the prosecution barrister John Price KC pushed for a re-trial – and to their even greater astonishment a jury convicted him again, after a 33-day trial.

The new case against Justin Plummer was constructed almost out of reheated hearsay evidence not relied upon at the original trial. Generally, courts are reluctant to allow hearsay because it is inherently unreliable – that is doubly true when it comes from the mouth of a convicted criminal who is long dead.

The supposed witness was Christopher Dunne, Plummer’s cellmate, who claimed that Justin had confessed to the murder. Dunne was a police informant with convictions for violence and dishonesty who had been diagnosed with schizophrenia – as he was dead, he could also not be called upon at trial. He was not called as a witness at the 1998 trial because he was ‘unreliable and not credible’ and he died the following year.

When Plummer’s conviction was finally overturned again, in 2025, judges at the Court of Appeal actually noted that the hearsay cell confession evidence, and the rag-bag other ‘new’ evidence that was used to convict him a second time, should never have been relied upon. They agreed that the conviction was unsafe and Plummer was acquitted. 

Justin Plummer’s case is featured in the latest issue of PROOF magazine, and the Justice Gap:  Justin Plummer: ‘If they thought they could get away with it again, they would’.

Plummer joined the Future Justice Project at an All-Party Parliamentary Group event in Parliament in February 2026. He told an audience in Portcullis House about his experience of being wrongfully convicted, and the fact that he will likely never get compensation for what he went through.