The CCRC referred the case to the Court of Appeal on 23 September 1997, and the conviction was quashed on 24 February 1998 when Lord Justice Rose, Mr Justice Holland and Mr Justice Penry-Davey ruled that the conviction was unsafe because the evidence of the main prosecution witness was unreliable.

This week a headstone was placed on the grave of Mahmood Mattan in a corner of Western Cemetery, Cardiff; the epitaph reads simply "Killed by injustice". Mattan's widow and his son Omar watched the proceedings quietly and then walked away to try to move on with their lives. But they cannot forget - and say they will never forgive.

On the morning of September 3, 1952, Mattan, a young Somali sailor, was taken from his cell at Cardiff prison, marched to the gallows and hanged for a murder he didn't commit. Seven weeks earlier, in a parody of a trial, he had been found guilty of slitting the throat of Lily Volpert, a Cardiff shopkeeper. The hearing at Glamorganshire Summer Assize in Swansea was so steeped in racial bigotry that even Mattan's defence solicitor described him as a "half-child of nature; a semi-civilised savage".

Despite his limited grasp of English, he did not have an interpreter and the jury did not know that the prosecution witness on whom the case hinged had altered his statement and been rewarded for giving evidence. It took 46 years and a dogged family campaign before the Appeal Court overturned Mattan's conviction and allowed his Welsh widow, Laura, to exhume his quicklimed body from its felon's grave at Cardiff jail and rebury it in consecrated ground.

Recently it emerged that the Home Office had paid compensation of about £700,000 (not £1.4 million as was widely reported, say the family), which is being shared four ways between Laura and the couple's three sons, David, 53, Omar, 51, and Mervyn, 50.

It might be expected that this, together with the erection of the headstone inscribed in both Arabic and English, a final act of dignity for Mattan, might enable the family to close the book on the miscarriage of justice that has blighted their lives. But the family say they feel that the money is tainted by their father's blood and that nothing will repair the damage caused by the decades of prejudice they suffered as "the children of the hanged man". They are seeking further compensation from South Wales Police for the arrest and unlawful execution of Mattan because it is the one card which they can play against the authorities: he cannot be brought back to life so they must try to shame those who helped to bring about his death.

"Part of me feels like taking the money, putting it in a pile and burning it outside the prison where they hanged my father, to show how little it means to us and how it can never pay for what they did," says Omar, a quietly spoken man. Both he and his brother Mervyn have given most of their share away to their own children and relatives. "Our father believed absolutely in British justice. Right until the last minute he didn't think he would be hanged because he thought the police would get the right man. And look what they did to him."

Nor does Laura, now 72, derive any comfort from the compensation. She still lives on the same Cardiff council estate and her face is drained of life - a legacy of 50 years of hardship and the loss of the man she calls her great love. "What does money matter really compared with the fact that he will never be able to sit down or go walking with his sons? It's nothing," she says. "I'm still devastated and I'll be angry until the day I die. This was a kind, gentle, loving father who respected me and loved this country and had so many plans for his family. He was an ordinary man but he was the best thing that had ever happened to me."

Mahmood Mattan met Laura Williams, a 17-year-old girl from the Rhondda Valley, while he was a foundry worker in Tiger Bay and she worked in a paper factory. Born in British Somaliland, he had gone to sea and settled in Wales. Tiger Bay and its bustling docks, where Indians, Chinese, Africans, Jews and Arabs worked shoulder to shoulder, was regarded at the time as a model of racial harmony. But in reality races were expected to stick with their own, and when Laura and Mattan began courting there was outrage in the community. People threw buckets of water at Laura, calling her a "black man's whore".

When the couple married three months later, few of their neighbours would speak to them. For a year - one which Laura describes as the "happiest of her life" - the couple enjoyed some respite from the racist taunts when they moved to Hull with their first two sons after Mahmood found work there. They should have stayed.

On the evening of March 6, 1952, Lily Volpert, a 41-year-old unofficial money-lender, answered a knock on the door of her Cardiff shop. Soon afterwards she was found by a neighbour lying in a pool of blood, her throat cut from ear to ear. Nine days later Mattan was charged with the murder. Police raided the Mattans' flat and found a broken shaving razor but no bloodstained clothes or any sign of the stolen £100.

Despite having alibis backed by witnesses, Mattan was convicted on microscopic flecks of blood on his shoes and the word of Harold Cover, a Jamaican who testified that he saw Mattan coming out of Volpert's shop. But the shoes had been bought secondhand and Cover was a violent criminal who was later jailed for life for the attempted murder of his daughter. The defence was not told that four witnesses had failed to pick Mattan out at an identity parade. Indeed one, a 12-year-old girl who had seen a black man near the shop at the exact time of the murder, told police that it was definitely not Mattan. They ignored her evidence.

The weeks her husband spent on remand were traumatic for Laura, now a mother of three young boys. The family's house was so close to the looming prison that if she looked out of her window at an appointed time she could see her husband waving a handkerchief from the window.

On the morning of September 3, Laura, still only 21, turned up at the jail as usual. As she stood outside the gate in torrential rain an official came out and pinned a notice to the gate. It stated that the execution of Mahmood Hussein Mattan had taken place at 8am and had "gone without a hitch". Laura had not even known it was going to happen. It was their son David's fourth birthday. Laura collapsed and was taken home by her mother. She was inconsolable and would not answer her door for nearly three weeks. Official reports say Mattan was 28 when he died, but the family insists he was only 24, having added four years to his age in Somaliland to enable him to go to sea.

"All I remember about that time is my grandmother looking after us and being told that mother wasn't well," says Omar, a painter and decorator. "Up until I was eight I was told that my father had died at sea, and I believed it. Then one day the Salvation Army band was playing near our house and I went out to sing with them. One of the leaders said: ‘We don't need the sons of hanged men.' Until I was about 12 that knowledge felt like a cancerous growth in my head. I can still remember my Dad carrying me on his shoulders, and when he bought me a huge teddy bear."

Omar spoke to the Imam who spent the final hours with Mattan in his cell before the execution. "He told me that he'd said to my father: ‘Now is the time to make your peace with God.' My father replied: ‘I have no peace to make. My conscience is clear.' "

The boys had problems enough growing up as half-caste children in a racially intolerant era, but having a hanged man as a father increased the stigma. They lived in abject poverty. "We were incredibly poor. We had to rely on charity for our clothes and food and roll up pieces of cardboard for the fire because there was no coal," says Omar. But Laura always told her boys that their father was innocent and they fought a long campaign to clear his name. Their first attempt to have the conviction overturned was refused in 1968 by the then Home Secretary, James Callaghan. But in 1996 they achieved their first breakthrough when permission was granted to have the body exhumed and reburied.

Even then, however, there was little dignity for the Mattans. "They wouldn't let us have a hearse," says Mervyn bitterly. "My father's body was carried in a dirty blue Transit van for the journey to the cemetery and his coffin was made of cheap plywood. The Home Office wanted it to be as low-key as possible. When they brought out the bodybag I touched it because I just wanted to feel close to him for a moment." In a further slight, the family, not the Home Office, had to meet the £1,400 cost of the exhumation.

As the campaign gathered strength, witnesses started to emerge. The 12-year-old girl, now an adult, came forward a second time to tell the family's solicitor about the identity parade where she ruled Mattan out. Then in 1997 came the biggest victory. The Criminal Cases Review Commission was set up to investigate alleged miscarriages of justice. Mattan's case was the first to be referred to the Court of Appeal where, in 1998, three appeal judges overturned the conviction.

What has upset the family most recently are reports that they are somehow living the high life on their compensation payments. They say that reports of them investing their money in property deals are rubbish. "I have given most of mine away," says Mervyn. "It wouldn't matter to me whether it was £50,000 or £2 million. It doesn't interest me. Money cannot buy back my father's soul and give us back the happy life he could have had with us."

To this day Laura still talks to her husband. Omar says: "She still sits in the armchair speaking to him. Quite often she tells him: ‘See? You should have listened to me. If we'd stayed in Hull like I wanted, then none of this would have happened and you'd still be here.' " Shamefully for British justice, she is right.

In a landmark case the family of a man hanged 49 years ago for a murder he did not commit has received £1.4m in compensation, it emerged yesterday.

Mahmood Mattan, a Somali, was executed in Cardiff jail in 1952 after being convicted of slitting the throat of Lily Volpert, a pawnbroker and moneylender, at her shop in the Tiger Bay area of the city.

His widow, Laura, only found out he had been hanged when she went to visit him and discovered a notice of his death pinned to a door in the prison.

The family launched a campaign 10 years ago to get Mattan's name cleared. The case went before the criminal case review commission in 1997 and the conviction was quashed in the court of appeal the following year.

The compensation paid by the Home Office is the first award to a family of a person hanged for a crime they did not commit.

The £1.4m was shared between Mrs Mattan, 79, and the couple's three sons David, 53, Omar, 51 and Mervyn, 50. Relatives and friends who joined the campaign to clear Mattan's name were also given a cash handout.

Mrs Mattan, who lives in Ely, Cardiff, did not want to talk yesterday, but her son, Mervyn, said: "The misery for my mother has never gone away and never will. For years she had no help, she was on her own. The money means nothing compared to the suffering she has been through.

"She says she will be angry about it until her dying day. It should never have happened."

Mattan, 28, was arrested within hours of the murder in March 1952. Despite having alibis backed up by four separate witnesses, he was convicted at Glamorganshire assizes in Swansea in July 1952. An appeal was rejected and he was executed in September.

But in the 46 years between his execution and exoneration new evidence emerged that the seaman, who only spoke halting English, was the victim of a miscarriage of justice inflicted by a racist police force and intolerant community. Even his defence lawyer called him "a half child of nature, a semi-civilised savage".

At his trial the prosecution case relied on the evidence of Harold Cover, a Jamaican, who was jailed for life in 1969 for trying to kill his daughter.

He claimed to have seen Mattan in the area where Volpert was killed but the jury was never told that he was paid to give evidence or that four witnesses had failed to pick out Mattan in an identity parade.

Vital information about another Somali, Tehar Gass, who had also been seen by Cover in the area at the time of the murder was also withheld from the court. Two years later Gass was tried for murder and was found not guilty by reason of insanity. The judge said Gass was prone to violence against women and was obsessed with knives.

Mrs Mattan, who is Welsh, endured years of abuse from the local community including taunts of "black man's whore" from neighbours who forced the couple to live apart.

"If Mahmood and I had been living in Biblical times we would have been stoned to death," she said after her husband was exonerated in the court of appeal.

"He was a lovely man. He was the best thing that happened to me. He was gentle. He loved this country, and he treated me like a human being, a queen."

In September 1996 Mrs Mattan won the first court battle to clear her husband's name when she was permitted to have his quicklimed body exhumed from its felon's grave in Cardiff jail and reburied.

Mervyn Mattan said yesterday: "The piece of my father that they have given back to me is in the form of a financial award. But the money cannot buy back his soul. They stole my father's life and no amount of money can change that."

Court of Appeal quashes man's murder conviction 46 years after he was executed, reports Adrian Lee

A widow's unceasing campaign to clear the name of her husband ended in triumph yesterday, 46 years after he was hanged for the murder of a shopkeeper.

Laura Mattan, now 68 and seriously ill with cancer, broke down as the Court of Appeal quashed the conviction of her husband, Mahmood Hussein Mattan, who was executed at Cardiff prison in September 1952. Mr Mattan, born in Somalia, was executed seven weeks after being found guilty of the murder of Lily Volpert, 42, a pawnbroker, at her shop in Cardiff docks on March 6, 1952.

The throat of the spinster was cut with a razor and she had been robbed of £100. Mr Mattan, a former seaman who had settled in Wales and married six years previously, was hanged at the age of 28 mainly on the evidence of Harold Cover, a witness who placed him at the scene.

Mr Cover, now 78, was at the court yesterday as three judges were told that his account was now discredited. His description of the likely killer matched that of another Somali, Tehar Gass, down to his distinctive gold tooth. Gass was accused of another murder in 1954, after the stabbing of Granville Jenkins, a wages clerk, but was found to be insane. After his release from Broadmoor, he was deported to Somalia.

Mrs Mattan, who has four sons, will now seek a posthumous pardon for her husband, a police inquiry and is likely to receive substantial compensation. The family will seek up to £2 million. The case was the first murder to be referred back by the Criminal Cases Review Commission, set up last year as a "court of last resort" to spot possible miscarriages of justice. The appeal court ruled that the case against Mr Mattan was "demonstrably flawed".

Mrs Mattan stood praying outside Cardiff prison as her husband was hanged on a rainy morning. Then aged 23, she was left with little income but never forgot her husband's protestations of innocence. His final request was that his body should not be taken from the prison until his name was cleared.

Two years ago, as the case began to swing her way, but her own health declined, Mrs Mattan had the remains exhumed and reburied at a cemetery in Cardiff. Her own final wish is that she will lie by his side. Before then, because he was a Muslim, the family will arrange a ceremony to release his soul.

Mrs Mattan gasped as the decision was announced and then began crying. Her sons Omar, 48, and Mervyn, 46, clapped. "I feel that I have waited forever for this day," Mrs Mattan said. "I still can't believe it." Her main emotion was one of anger that it had taken such a short time yesterday to destroy the case against her husband.

Mr Mattan was a merchant seaman when the couple met in the late 1940s. She was one of 11 children; her family did not agree with her choice and for much of their marriage they were forced, by racial prejudice, to live in separate houses in the same street.

At the time of the murder, Mr Mattan had just been paid off by a steelworks. He was regarded as a rogue, who loved to gamble on greyhounds and was a regular card player. But he had no history of violence.

Mrs Mattan's campaign was taken up three years ago by Bernard and Lynne de Maid, solicitors in Cardiff. It was discovered that evidence was withheld from the defence at the original trial and that Mr Cover identified Mr Mattan after a £200 reward - enough to buy a house in the city - was offered by the victim's family.

Mr Cover, who claimed to have seen Mr Mattan leave the shop on the night of the murder, was later convicted of the attempted murder of his daughter with a razor and became a possible suspect in the Volpert case. Without his evidence, only the embers of the prosecution case remained, Michael Mansfield, QC, told the court yesterday. John Williams, QC, for the Crown, conceded that there were so many inconsistencies in Mr Cover's evidence that he was no longer a credible witness. The court was also told that one of the investigating officers, Detective Inspector Ludon Roberts, who died in 1981, was aware that Mr Cover's description did not match that of Mr Mattan, but that evidence was not put before the jury. Gass, now thought to be the most likely killer, was interviewed and admitted visiting the shop earlier on the day of the murder but, again, the jury was not told.

After Mr Cover's conviction for attempted murder in 1969, James Callaghan, then Home Secretary, was approached by the family but did not refer the case to the Court of Appeal.

Speaking afterwards, Mrs de Maid said she believed the pressure put on Cardiff City Police, now part of the South Wales Constabulary, to solve the crime quickly meant there was never a proper investigation. "The campaign to clear her husband has kept Mrs Mattan alive. Her husband was the only love of her life."

Mr Cover left court yesterday insisting he played no part in the killing and that he had always told the truth. Quashing the conviction, Lord Justice Rose, vice-president of the Court of Appeal, said Mr Mattan's death and the length of time taken to dismiss the conviction were matters of profound regret. "The court can only hope that its decision today will provide a crumb of comfort for his surviving relatives." He said the Criminal Cases Review Commission was a necessary and welcome organisation without which this injustice might never have been uncovered. The commission is also expected to refer the case of James Hanratty, hanged 35 years ago for the A6 murder of Michael Gregsten and the rape of his lover, Valerie Storey, to the Court of Appeal in the next two months. It has already referred the case of Derek Bentley, hanged 46 years ago, to the court and a full hearing is expected later this year.

Last night South Wales police expressed sympathy to the Mattans and said that the case would be re-examined.

A man hanged 45 years ago for killing a woman shopkeeper has had his murder conviction overturned by three Appeal Court judges.

The case of the Somali seaman Mahmood Hussain Mattan was re-examined after the Criminal Cases Review Commission agreed last autumn to refer it back to the Court of Appeal in London.

Mr Mattan was hanged in September 1952 - the last man to be executed at Cardiff prison - after being convicted of murdering Lily Volpert whose throat was cut in an attack at her shop in the city's docklands.

His family, including his widow Laura, have fought a long campaign to clear his name because of their belief that he was wrongly sent to the gallows on wholly unreliable evidence from a prosecution witness.

Mr Mattan, 28, a father of three, was arrested within hours of the murder in March 1952.

He was convicted at Glamorganshire Assizes in Swansea in July of that year. An appeal was rejected in August and he was executed the following month.

After hearing new evidence in the case, Lord Justice Rose, the Vice-President, sitting with Mr Justice Holland and Mr Justice Penry-Davey, overturned the murder conviction.

A Somali seaman who was hanged 45 years ago for murdering a woman shopkeeper had his conviction quashed by the Court of Appeal yesterday.

Three judges ruled that the conviction of Mahmood Hussein Mattan was unsafe because the evidence of the main prosecution witness was not reliable. Mr Mattan, who was hanged in September 1952 and was the last man to be executed at Cardiff prison before the death penalty for murder was abolished, had been convicted in July that year of murdering Lily Volpert.

Her throat was cut in an attack at her shop in the Cardiff docklands in March 1952 and Mr Mattan, then 28 and a father of three, was arrested within hours of the murder. The family of Mr Mattan, including his widow, Laura, who have fought a long campaign to clear his name, will now be able to claim compensation for the wrongful conviction.

Mrs Mattan said: "I'll probably be angry until my dying day. He has been cleared, but it should never have happened in the first place. He should have been cleared way back when."

It will be the first time that Sir David Calcutt, the independent compensation assessor, will have to assess compensation for the personal representatives of a hanged prisoner.

Mr Mattan's case was one of the first to be referred back for review by the Court of Appeal by the Criminal Cases Review Commission since it was set up under the 1995 Criminal Appeal Act. There were gasps of relief from his family and a burst of applause when the three judges, Lord Justice Rose, Mr Justice Holland and Mr Penry-Davey, announced their decision.

Earlier John Williams, QC, for the Crown, had told the judges that the Crown now accepted that the evidence of Harold Cover, a carpenter, 78, which had been "central to the conviction" of Mr Mattan, was not credible.

He told the judges that late on Monday "further information" had come to the attention of the Crown Prosecution Service which "brings very much into question the credibility of Harold Cover".

In his judgment quashing the conviction, Lord Justice Rose said the basis of Cover's evidence was that he had seen Mr Mattan leaving the doorway of the shop at 8.15pm, when the prosecution claimed the murder must have been committed.

At the trial Mr Mattan's defence had been the alibi that he had left a cinema at 7.30pm and had gone home. In 1969, said the judge, Cover was convicted of attempting to murder his daughter by cutting her throat with a razor and was sentenced to life imprisonment.

Mr Mattan's case was then referred to the Home Secretary on the basis that Cover's conviction "suggested that he might himself have murdered Miss Volpert". But in February 1970 the then Home Secretary wrote to the family saying he saw no reason to re-open the case.

Lord Justice Rose said that in referring the case to the Court of Appeal last year, the Criminal Cases Review Commission had regard to the fact that the statement made by Cover on March 7 1952, the day after the murder, differed materially from his evidence before the jury. This statement had not been disclosed to the defence.

Lord Justice Rose said: "In addition, the defence were unaware that four witnesses, all of whom had seen a man in or near the shop shortly before or about the time of the murder, had failed to pick out the appellant in an identity parade."

A further witness, who was 12 in 1952, had said Mattan was not the man she had seen near the shop at the time of the murder. Although these matters formed the basis of the appeal, Lord Justice Rose said there were further developments which had taken place up to and including the date of the hearing. Two weeks ago the prosecution had furnished the defence with copies of entries made in a notebook by one of the senior officers who had investigated the murder, Det Insp Roberts, who is now dead.

Lord Justice Rose said that one entry said that the man seen by Cover had been traced and noted the name, Tahir Gass, and another referred to Cover identifying the Somalian he saw in the porch of the shop as Mr Gass. It emerged last week, said the judge, that Mr Gass, who may no longer still be alive, had been tried for a murder in 1954 and had been found not guilty by reason of insanity.

In describing the latest evidence disclosed on Monday night, Lord Justice Rose said the defence had received a copy of a telex circulated in June 1954 which contained a description of Tahir Gass as "wanted for that murder".

The description referred to him as having a gold tooth. This was of significance in Mr Mattan's case, said Lord Justice Rose, as Cover in his witness statement, which had not been disclosed to the defence, said he thought the man he saw coming from the shop doorway had a gold tooth. Mr Mattan did not have a gold tooth. Mr Gass, said the judge, was prone to violence against women and was obsessed with knives.

According to the Home Office, Mr Mattan is the first person in living memory to have had his conviction quashed after being hanged for murder. Timothy Evans, who was hanged for the Notting Hill murders of his wife and a daughter subsequently attributed to Reginald Christie, received a posthumous pardon.

The body of a man who was hanged 44 years ago for a murder his family maintains he did not commit was exhumed from a prison grave and reburied in a public cemetery yesterday.

Mahmood Hussein Mattan, 28, a Somali seaman, was hanged in Cardiff Jail in September 1952 for the murder of Lily Volpert, a shopkeeper whose throat was cut during a robbery in the city's docks area.

Laura Mattan, his Welsh wife, and her three sons have always claimed that he was innocent and allege that another man, who gave evidence against Mattan and had a string of convictions for violent crime, was the killer.

A detailed legal submission will be delivered to Michael Howard, the Home Secretary, next week seeking a referral of the case back to the Court of Appeal.

Mrs Mattan, 67, and her sons Omar, Edward and David, watched as the body was taken from the jail for reburial in the Muslim section of Western Cemetery.

Bernard de Maid, a solicitor who has donated his services to the campaign, said that Mattan's trial had turned on the evidence of one witness who claimed to have seen him leaving Mrs Volpert's shop in Cardiff at the time of the murder.

The witness's convictions for violence were not made known to the jury and 17 years later he was jailed for life for the attempted murder of his stepdaughter, whose throat was cut.

Mr de Maid said: "We say that events since 1952 exonerate Mattan and implicate this other man." The man has since been released from prison and is believed to be living in the Cardiff area.

Mr de Maid said other features of the case form grounds for a successful appeal. He said Mattan's English was limited and he did not have the aid of an interpreter, he was defended by an inexperienced counsel and was the victim of racism, having been referred to as "a semi-civilised savage" by his own barrister.