The family of Stefan Kiszko said last night that they hoped Ronald Castree “rots in Hell” for ruining the lives of two families.

Ann Kiszko, the aunt of the former Inland Revenue tax clerk, is one of the few surviving members of the Ukrainian clan who came to work in the cotton mills of Rochdale after the Second World War.

She always knew that Stefan, a lumbering giant of a man whose size belied his gentleness, was innocent of Lesley Molseed’s murder. It was simply not in his nature.

He was jailed for life by Leeds Crown Court in July 1976, and spent 16 years in prison protesting his innocence. The Court of Appeal quashed the conviction finally in 1992 after hearing evidence suggesting conclusively that he could not have been the murderer. It was, as one MP said at the time, the “worst miscarriage of justice of all time”.

Mrs Kiszko, who still lives in Rochdale, said of Castree: “He has ruined a lot of lives. The poor family of Lesley Molseed suffered 32 years before finally getting justice, while Stefan spent the best years of his life in prison.

“Castree has had the best years of his life already. He killed that girl when he was 21, just a couple of weeks after having a baby himself. Unbelievable.

“I feel sorry for his wife and children. They have lived with this monster for years without knowing what he has done. They are the innocent ones. Our family knows what it is like to be marked as being associated with a child killer.

“But he can rot in Hell. I hope the bastard gets what is coming to him inside prison.”

Stefan Kiszko’s conviction remains a blot on the record of the West Yorkshire force and the criminal justice system. He was arrested two months after the schoolgirl’s murder. Officers were soon convinced that this “man-child” before them was the killer with a bizarre sexual kink.

His immaturity was, however, the result of a condition called hypogonadism, meaning his testicles were undeveloped. He had been receiving hormone injections in the months leading up to Lesley’s disappearance.

The prosecution relied upon a confession offered by a bewildered and exhausted man without recourse to a solicitor after two days of questioning by police. It was retracted later but the damage had been done.

The innocent man’s fate was sealed when David Waddington, his defence barrister and later Home Secretary, ran a defence of manslaughter due to diminished responsibility. Mr Waddington, now Lord Waddington, suggested that his client was subject to uncontrollable urges brought on by the hormone treatment.

In jail Mr Kiszko was vilified, beaten up by fellow inmates and kept in solitary confinement for his own safety. In Armley Jail the hard cases called him “Oliver Laurel” because he had the girth of Oliver Hardy and the permanently perplexed air of his sidekick, Stan Laurel.

His mother, Charlotte, meanwhile, was indefatigable in her determination to see him released.

Lord Lane, the Lord Chief Justice, finally declared the conviction unsafe after hearing that Mr Kiszko could not have been the source of semen on Lesley’s underwear, and thus the murderer, because his condition made him incapable of producing sperm.

An investigation was launched into why this information was not disclosed to the defence in the 1976 trial.

Mr Kiszko, suffering from schizophrenia, remained in hospital for a further nine months before he was fit enough to return home. He did not enjoy his freedom for long. He died prematurely from a heart condition a year later. Five months later his mother also died.

Campbell Malone, the Wigan-based lawyer who led the appeal campaign, said: “Charlotte said to my wife that in some ways she was glad he died first because she knew he would have grave difficulties surviving.”

The miscarriage of justice meant that the real killer was still out there. It spawned conspiracy theories that live on today on the internet.

In 1994 Detective Superintendent Dick Holland, an officer who became a public figure during the Ripper inquiry, and Ronald Outteridge, a retired forensic scientist, were summoned on charges relating to the apparent failure to disclose evidence during Mr Kiszko trial. The charges came to nothing.

Mr Malone said that Charlotte Kiszko had always urged him not to allow people to forget her son’s name and the injustice he suffered.

“The surest way of demonstrating that he was an innocent man is for someone else to be properly and safely convicted on the basis of evidence,” he said. “That represents closure.”

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