A HEARTBROKEN mother whose son is serving more 20 years for murder is raising awareness of what she believes is a flaw in the law.

Phyllis Kevern, from Falmouth, feels that her autistic son Trewen fell victim to the common law of joint enterprise, which allows courts to convict more than one person to be charged and convicted of the same crime.

"I feel like I've let my son down by taking in another member of the family who did the murder.

"I want to make people aware that my son is not a murderer and that he's innocent - this sort of conviction could happen to anybody," said Mrs Kevern, who has four children.

In December 2016, Kevern, aged 25, of Tresillian Road, and accomplice Kevin Cooper, aged 35, of Carharrack, were jailed for the murder of a David Alderson, a man affectionately known as "grandad" by the Kevern family.

Kevern lost his appeal against his conviction last November and is now serving a minimum of 20 years before he is eligible to apply for parole.

At the Court of Appeal he argued that his trial, in which he put the blame on Cooper alone, was unfair.

But in a half-day hearing in London, Lady Justice Macur ruled that he had no arguable case that his conviction should be quashed.

"This was a case where we have no doubt this applicant had all the points that could be made on his behalf made before the jury," she said.

Alderson, 72, was found floating face down in a pool of water at a disused copper mine near Bissoe, in January 2014.

He had multiple injuries to his head and had been dragged into the pool, where he was held under the water until he died.

On appeal, lawyers for Kevern argued that he should have been tried separately to Cooper, who had refused to finish giving his evidence at the trial.

It meant Kevern's defence team had been unable to cross-examine him fully in order to show he was an "inveterate liar."

But Lady Justice Macur, sitting with Mrs Justice Carr and Judge Peter Collier QC, said the judge was entitled to continue the trial after Cooper refused to go back into the witness box.

Mrs Kevern, who held a fund-raising event for JENGbA (Joint Enterprise: Not Guilty by Association) at the Dracaena Centre on Saturday, added: "Trewen is a big boy - he's 6ft 4ins, 27 stones and has size 14 feet - but he's not a murderer. People who know him, know.

"We're starting to see joint enterprise cases being overturned now and that's what I want for him.

"I've just visited him in Swaleside Prison (Kent). He's been put on suicide watch a couple of times. He has a glazed look about him. Emotionally he's shut down."