After five years in prison for a murder he said he didn’t commit, Dwaine George’s options were running out. Found guilty by a jury and rebuffed by the court of appeal, he took one of the few options left open to him: he entrusted his future in a group of law students.

Eight years on, his decision has now been justified and his conviction for murder quashed after a dogged campaign by around 30 students in the first success for a university Innocence Project in Britain.

Mr George, a member of the Cheetham Hill gang, had been sentenced to a minimum of 12 years after a jury found him guilty of murder in 2002 following a gangland feud.

He claimed he was eating at a friend’s house at the time of the murder, but was convicted after being identified as part of a group that shot dead teenager Daniel Dale in Manchester.

But the Court of Appeal ruled that new scientific evidence about gunshot residue, found on a coat at Mr George’s Manchester home on his arrest in 2001, meant that his conviction was unsafe.

It comes too late to save him from any more jail time – he had already been released last year – but ends a long campaign for the 30-year-old who said he “said from day one that it wasn’t me”. In quashing the conviction, judge Sir Brian Leveson said yesterday: “We pay tribute to the work of the Innocence Project and Pro Bono Unit at Cardiff Law School, which took up the appellant’s case and pursued it so diligently.”

The protracted saga to clear Mr George’s name has highlighted the time and difficulty it takes for a conviction to be quashed in Britain.

After his application to appeal was first turned down in 2004, Mr George, now 30, wrote to the newly founded Innocence Network UK, a small group of linked British law schools inspired by similar projects in the United States.

Students from Cardiff Law School took on the case and over four years studied court papers and examined scientific papers while studying for their own law degrees. They visited Mr George in prison and secured their own expert witness reports that questioned the confidence that the residue could used to prove his guilt.

“After seeing Dwaine, we agreed it renewed our desire to overturn his conviction,” said Caitlin Gallagher, 27, who worked on the case. “It made us more driven.”

Four years after they filed papers in the case, their confidence of Mr George’s innocence was vindicated. “From the first read of the papers, I was always surprised that the case had got to trial and I was very surprised that he had been convicted,” said Sarah Magill, 29, one of the few students now working in criminal law.

“I’m a staunch supporter of trial by jury but sometimes they make the wrong decision. I’m very relieved for Dwaine, but I’m very mindful that a family will now feel that they haven’t achieved justice for the death of their son.”

The family of Mr Dale, the victim, have said they believed that the court rightly convicted Mr George for murder.