There have undoubtedly been many miscarriages of justice in our legal system over the years. But none of them is quite as tragic and haunting as the conviction of Welshman Timothy Evans and his subsequent execution in March 1950 for a crime he did not commit.
Timothy Evans was born in Merthyr Tydfil on 20 November 1924. It was not an easy childhood; shortly before Timothy was born his father ran off and left the family to cope by themselves. His mother remarried in 1929 and the family soon consisted of Timothy, his elder sister Eileen and a younger half sister called Maureen.
The young boy was slow in nearly all his developmental milestones and, as the victim of a tubercular sore on his right foot - something that never totally healed - he was often away from school for long periods. As a consequence, when he left school Timothy Evans was virtually illiterate and could barely read and write his own name.
The family moved to London and Evans began work as a painter and decorator for a while. He tried moving back to Merthyr Tydfil in 1937, working in the coal mines around the town, but found the job too difficult because of his foot.
By 1946 he was again living in London, in the Notting Hill area, and on 20 September 1947 he married Beryl Thorley. Within months she was pregnant, and Geraldine Evans was born on 10 October 1948.
Soon after their marriage the young couple moved into a top floor flat at 10 Rillington Place, close to Ladbroke Grove. Living in the ground floor flat of the house were John Christie and his wife Ethel.
The relationship between Timothy and Beryl was not easy: angry quarrels and occasional physical violence were part of their life together. When, late in 1949, Beryl announced that she was pregnant again, their financial situation was so fraught that an abortion - illegal in those days - was considered the only option.
On 30 November Evans turned up at Merthyr Tydfil police station, stating that his wife had died after he had given her some mixture to abort the baby. He had disposed of the body, he claimed, in a drain outside the house.
No body was ever found and Timothy Evans changed his story. John Christie, he said, had agreed to perform the abortion and Beryl had died during the procedure. The Evanses' daughter Geraldine had been given to someone to look after but Christie, Evans claimed, would not let him see her.
A police search of 10 Rillington Place found Beryl's body wrapped in a cloth in the wash house at the back, and alongside her was the body of Geraldine. Both had been strangled.
Clearly under stress, Timothy Evans was asked if he had killed his wife and child. He replied "Yes". It was later revealed that much of his confession was actually dictated to Evans by police investigators and there was an almost total lack of forensic evidence.
The trial - according to the legal procedure of the day, for the murder of Geraldine, not his wife - began on 11 January, with Timothy Evans now claiming that Christie had committed the murders. It lasted three days and the jury took only 40 minutes to return a guilty verdict. Evans was hanged on 9 March 1950, and the execution was carried out by Albert Pierrepoint.
Three years later police uncovered a number of bodies at 10 Rillington Place, all of them women and all the victims of John Christie. At least six of the bodies were hidden under floorboards and in the wash house - Christie even used the thigh bone of one woman to prop up his garden fence. And yet the police, in their searches three years earlier, had totally missed this vital piece of evidence, just as they had missed the bodies lying almost casually around the house. It was evidence that might have saved Timothy Evans.
The motive behind the killings was certainly sexually driven, with Christie abusing the bodies after death. He admitted to the crimes and was hanged on 15 July 1953.
Amazingly, in the wake of Christie's conviction, an inquiry into what was termed a "possible miscarriage of justice" upheld the guilt of Timothy Evans. Intense debate and a long-standing campaign by Evans' sister - not to mention a hugely powerful exposé by journalist and writer Ludovic Kennedy - forced another inquiry in 1965.
The findings this time were clear that Evans had not killed his daughter - the death of Beryl remained a mystery and, since by now both Evans and Christie had already gone to the gallows, it was impossible to come to a firm conclusion.
As a result of the second inquiry Timothy Evans was given a royal pardon in October 1966. His conviction and execution were tragic, a man of limited intelligence being brow beaten into a series of confessions that could, ultimately, lead only to the death cell.
The case of Timothy Evans was one of several that eventually contributed to the abolition of capital punishment in Britain but that bald statement cannot even begin to catch the human tragedy of the affair. The case remains one of the most dreadful miscarriages of justice ever to blight the British legal system.