An anonymous allegation on the Crimestoppers phoneline led to the multimillion-pound corruption investigation that nearly destroyed Ali Dizaei’s career and reputation as one of Britain’s high-flying Asian policemen. The claim that Mr Dizaei: inquiry began after an anonymous telephone tip-off Dizaei, then a superintendent, was a burglar led to a tap on his phone and the start of investigations that included cameras recording his every movement.

For the first time in Not One of Us, serialised from tomorrow in The Times, Mr Dizaei tells the full story of how he nearly fell from grace as the victim of the “self-appointed knights of integrity” at Scotland Yard.

In 1999 investigations began into Mr Dizaei over allegations involving corruption, drug use, prostitutes and spying for Iran.

Suspended while waiting to go on a course for future chief constables, Iranian-born Mr Dizaei was finally cleared at the Old Bailey in 2003 of perverting the course of justice and misconduct in public office.

In Not One of Us Mr Dizaei, who is now waiting to learn if he is to be promoted to the rank of commander at Scotland Yard, writes scathingly of a 44-strong investigation that he says was driven by a handful of officers who, he believes, were out to destroy his reputation and career.

He describes how the investigators scrutinised the bank accounts of his brother and father, a former Iranian policeman, and undercover officers tried to befriend him and give him “integrity tests”. He saves his greatest criticisms for Chief Superintendant Barry Norman, the man who lead the investigating team, named Helios, and now commands police in Islington, North London.

Mr Dizaei describes how his outspoken views on race and his unorthodox lifestyle and open marriage made him enemies and provided fuel for the investigators.

Mr Dizaei, who was reinstated to become a chief superintendent in Hounslow, West London, admits that he has made mistakes and says that he has changed, but the story of his struggles will not help the police effort to recruit more black and Asian officers.

The Metropolitan Police Service (MPS) was warned yesterday by chief constables that it would take 17 years to get enough officers from ethnic backgrounds to mirror their communities and positive discrimination may be necessary.

Sir Ian Blair, Commissioner of the Metropolitan Police, and his officers are awaiting the fall-out from the book. A police statement last night said it was “a matter of regret that Chief Superintendent Dizaei has felt it necessary to write this book”.

The statement said that there were “exceptional circumstances surrounding this case and the Metropolitan Police believes that both the service and Chief Superintendent Dizaei have moved on since then. Although we do not believe it is in the best interests of the MPS to see this book published, neither do we believe that it is in the Met’s best interests to prevent its publication.”

The statement adds: “Chief Superintendent Dizaei received ‘words of advice’ in two areas where he acknowledged that his conduct had fallen below the standards expected of a police officer. Chief Superintendent Dizaei has provided a copy of the manuscript to us. It has been read and all the individuals cited have been advised and offered our support. Despite the outcome of the trial, their actions were vindicated by an independent review and we do not believe that criticism of Chief Superintendent Barry Norman, other members of the investigating team or other MPS individuals cited in the book, is either fair or warranted. As the Recorder of London, who presided over the trial, said in his judgment, ‘the fact is that this investigation was necessary’. He went on to say: ‘It is apparent that the investigation had to be begun and continued as it was, bearing in mind that the investigation was into a very senior police officer. So that not only was his integrity under question, but also that of the police force’.”

Life and times

— 1962 Born in the Iranian capital, Tehran. His grandfather and father both held senior positions in the city’s police force

— 1986 Joins Thames Valley Police

— 1999 Transfers to the Metropolitan Police as a superintendent

— 2000 Surveillance operation Helios mounted against him, accusing him of being involved in drugs, prostitution and spying for Iran

— 2003 Acquitted at the Old Bailey of all charges and reinstated. Awarded £60,000 compensation

— 2004 Independent Police Complaints Commission calls Operation Helios “seriously flawed”

— 2007 Awaiting possible promotion to commander

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