A retired police officer is under a criminal investigation over the wrongful conviction of Andy Malkinson for a rape he did not commit, the police watchdog has said.

The former Greater Manchester Police officer is being investigated for allegedly perverting the course of justice and misconduct in public office in relation to Mr Malkinson’s trial 20 years ago, the Independent Office for Police Conduct (IOPC) said.

The former officer and three other officers, who are also retired, are also being investigated for alleged gross misconduct.

Mr Malkinson was exonerated last year after suffering the longest miscarriage of justice of the 21st century.

Judges at the Court of Appeal were told of long-undisclosed DNA evidence that showed another man must have been the rapist in an attack on a woman in 2003.

No forensic evidence ever linked Mr Malkinson to the victim and he did not bear a facial injury that she had inflicted upon her attacker as she fought to defend herself.

He did not look like her initial description of the rapist and there was no evidence to link him to the secluded scene of the crime, near Bolton.

Mr Malkinson spent 17 years in jail protesting his innocence and a major judge-led inquiry is continuing into how the wrong man was convicted.

The decision to investigate the four officers comes after the IOPC took over a review into how GMP had itself handled complaints from Mr Malkinson.

An IOPC statement said that it was looking at how GMP came to identify Mr Malkinson as the key suspect and whether witnesses had been offered incentives to pick him out.

The watchdog said it was also investigating whether there had been a failure to disclose information that may have helped Mr Malkinson at his trial and it was also looking at whether officers followed the “appropriate processes” in how Mr Malkinson had been identified.

The watchdog said it was also investigating how GMP handled and disposed of evidence.

During Mr Malkinson’s successful appeal last year, it emerged that the original DNA samples recovered from the victim and her clothing had been destroyed.

Catherine Bates, IOPC Regional Director, said: “Mr Malkinson is a victim of one of the worst miscarriages of justice in British history.

“Following a detailed review of evidence spanning a period of more than 20 years, we have now informed four retired GMP officers that they are under investigation for potential gross misconduct.

“One of the officers has also been notified that they are under criminal investigation for potential misconduct in public office and perverting the course of justice in relation to their actions during the police investigation and subsequent trial.

“We will continue to keep Mr Malkinson and GMP updated on our progress.”

Emily Bolton, Mr Malkinson’s lawyer at the legal charity APPEAL, welcomed the IOPC’s decision to continue its investigation.

“Andy’s wrongful imprisonment was not an unavoidable accident,” she said.

“Police accountability isn’t optional – it’s essential. Andy, his family, and the rape victim in this case all deserve justice.”

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