The victims were shot in a lay-by on the A6

Hanratty, one of the last people to be executed before the abolition of capital punishment in the UK, had always claimed he was 250 miles away from the scene - in Rhyl, north Wales.

But on Friday, the three judges ruled that DNA evidence had established his guilt "beyond doubt".

Lord Woolf, the Lord Chief Justice, said: "In our judgment ...the DNA evidence establishes beyond doubt that James Hanratty was the murderer."

He added that the DNA evidence "made what was a strong case even stronger".

Family fury

Reacting angrily to the judgement, Hanratty's brother Michael claimed it was "the last cover-up".

"I waited 40 years to get here thinking I would get justice to have it thrown up in my face," he said.

Michael Hanratty said he had been denied justice

"This is not just a miscarriage of justice - this is murder."

But Detective Inspector Stewart Trail of the Metropolitan Police, who led the re-examination of evidence, said modern DNA techniques had supported the original verdict.

"We hope that today's result will finally draw a line under the speculation which has surrounded this case for nearly 40 years," he said.

"We have carried out a full and thorough investigation which has served only to reinforce the original trial verdict."

Notorious case

James Hanratty was convicted of murdering scientist Michael Gregsten on the A6 in Bedfordshire by shooting him twice in the head.

Mr Gregsten's girlfriend Valerie Storie was raped, shot five times and left for dead - she survived but was paralysed from the waist down.

I'm dying tomorrow but I'm innocent - clear my name

James Hanratty on the eve of his execution

Hanratty's family insisted he was the victim of a "distorted and fatally flawed trial".

They claimed that DNA evidence linking him to the crime may have been contaminated at the time of the original trial.

In April, Lord Chief Justice Woolf, Lord Justice Mantell and Mr Justice Leveson began to re-examine the safety of the 1962 conviction.

At the Appeal Court, barrister Michael Mansfield QC for Hanratty said the "distortion" of the original trial process was "in large measure" due to the actions of the senior police officer, who has since died, in covering-up evidence in several key areas.

It was alleged at the time that Hanratty came across the 36-year-old victim, Mr Gregsten and his 22-year-old girlfriend, Valerie Storie, inside a parked Morris Minor in August 1961.

They were confronted by a man with a gun who ordered them to drive to a remote lay-by, where Mr Gregsten was shot dead and Ms Storey was raped.

Hanratty was arrested, tried and convicted for murder.

Alibi ignored

The jury did not believe his story that he was in Rhyl at the time of the attack - despite the landlady of a B&B backing his claim.

In the years after his execution, numerous witnesses have come forward to support that story.

Valerie Storie: Conviction relied on her memory

His conviction was based largely on Miss Storie's recollection of the voice of her attacker.

Mr Mansfield, however, argued over the course of the appeal that she saw him for only a few seconds during the six-hour ordeal.

In 1999, the case was referred to the Criminal Cases Review Commission (CCRC), the independent watchdog set up to investigate alleged miscarriages of justice.

After carrying out its own investigation, it sent the case to the Court of Appeal.

But the case took another twist when DNA samples were taken from members of Hanratty's family.

DNA issue

They were checked against samples found on Miss Storie's underwear and a handkerchief wrapped around the murder weapon.

The results showed there was a 2.5 million to one chance that the samples came from someone other than Hanratty.

In March 2001, DNA sample extracted from Hanratty's exhumed body was matched by forensic experts to two samples from the crime scene.

The family believed that the DNA sample could have been contaminated.

Hanratty protested his innocence until his death. On the eve of his execution, he told his family: "I'm dying tomorrow but I'm innocent. Clear my name."