A dossier of at least 30 allegations of discrimination and political in-fighting at the top of the Metropolitan police and the Home Office has been compiled by the senior Asian officer at the centre of Scotland Yard’s latest race row.

The file contains private e-mails and other correspondence allegedly showing that one of Whitehall’s most senior mandarins colluded in a campaign to destroy his career and discriminate against him.

Assistant Commissioner Tarique Ghaffur, who is accusing the Met of racial discrimination, alleges that Moira Wallace, director of police and counter-terrorism at the Home Office, conspired with Sir Ian Blair, the Metropolitan police commissioner, to strip him of his responsibilities and sideline him.

His dossier includes correspondence between Wallace, Blair and Len Duvall, the chairman of the Metropolitan Police Authority, the Met’s governing body, in which they discuss Ghaffur.

All three deny behaving inappropriately. However, such is the sensitivity of the dossier that Ghaffur moved it out of his command suite on the fifth floor at New Scotland Yard to a safe in the offices of his London lawyers. “This is a personal thing. Tarique is very keen to show the involvement of the Home Office in all of this,” a friend said.

Met insiders say Ghaffur’s decision to take legal action was triggered by an explosive e-mail from Wallace that in effect sacked him as Olympics security chief. Sent to more than a dozen senior Met officers in March, it announced that Robert Raine, a senior Home Office colleague, would be taking charge of Olympic security, coordinating the work of 24 government agencies and police.

It was a post that Ghaffur had been given in 2006 by John Reid, then the home secretary, with Blair’s apparent blessing. Ghaffur had been immensely proud. “It would be helpful if no one described themselves as Olympic security co-ordinator,” Wallace wrote in one e-mail about the change. It was a thinly veiled reference to Ghaffur.

Ghaffur, Britain’s most senior ethnic minority officer, was incensed. He claims that the plot to oust him was hatched at a secret meeting between Wallace, Raine and Blair while he was on holiday. What embittered him further was his discovery that Blair was party to the change and had failed to alert him.

Instead, friends say, Blair refused to deal with Ghaffur’s complaints and delegated “the dirty work” of handling his removal from the Olympics post to Paul Stephenson, the deputy commissioner. “Tarique was on the ceiling; he was livid. They gave the Olympics job to Raine without any consultation or discussion,” said a friend.

In a further humiliation, Richard Bryan, the Met officer who was Ghaffur’s deputy for Olympic security, was moved to work for Raine at the Home Office. Blair assigned a more junior officer to work for Ghaffur.

Again, Ghaffur alleges, Blair failed to consult him. He told friends: “The Olympics thing was the last straw. You can only bloody take so much.”

Shami Chakrabarti, director of Liberty, the civil rights group, is among critics who say that, if true, the incident highlights the increasing encroachment of the Home Office into what should be independent policing matters. She will say in a speech this week to the Police Foundation that MPs should examine the way that the role of chief police officers has gradually been undermined by political interference from the government.

Ghaffur’s meticulously compiled dossier cites a catalogue of alleged abuses that stretch back to early 2005, when Blair began his troubled reign.

Ghaffur desperately wanted the job of deputy commissioner, but he – like others – was passed over for Stephenson, a man Blair was then confident he could work with.

Later in 2005 Ghaffur took the extraordinary step of consulting lawyers over Blair’s decision to cut staff in his directorate of specialist operations.

The spat that followed led Blair to remove Ghaffur, putting him in charge of traffic, firearms and Heathrow.

Ghaffur was furious, but then fences seemed to have been at least partly mended when Blair went along with Reid’s decision to make him Olympic security supremo.

Later the two rowed over Ghaffur’s request that he be allowed to represent the Met at this summer’s Beijing Olympics.

Blair had apparently decided that by 2008 Ghaffur, who has more than the statutory 30 years of police service behind him, would have retired. Ghaffur was told he would not be getting a contract extension. He complained and Blair relented but grudgingly made it clear he would get only one more year.

Then three months ago came Wallace’s humiliating e-mail. Ghaffur consulted his lawyers and decided to go public with his grievances.

Whether any of this can be blamed on racial bias will be for the courts to decide. For Blair, who pointed out last week that he has made a career of championing racial diversity, the prospect of being dragged before a tribunal on accusations of discrimination is an uncomfortable one.

The National Black Police Association says a final decision on suing the Met has not been taken and it is still trying to find an out-of-court solution.

However, it is prepared for a full-blown fight if Ghaffur does pick the “nuclear” option. “AC Ghaffur appears to have been treated extremely poorly. We are totally convinced of the legitimacy of this claim and will be fully supporting [him] with regard to this matter,” it said.

A senior officer who knows both men well said blame could be found on both sides. “People often say bad things about the commissioner, but I think this says more about Tarique than it does about Ian.

“I mean, for God’s sake, Tarique is the fourth most senior cop in the country. He’s a CBE and has a Queen’s Police Medal and he thinks he’s being discriminated against. I haven’t got a lot of sympathy.

“It’s an utter mess . . . the staff must think we are a bunch of numpties.”

According to his friends, Blair is “extremely worried” by this case. Ghaffur is just the latest Asian officer to sue the Met for discrimination. Commander Ali Dizaei, who was investigated and then cleared of corruption, received an £80,000 payout. The case of Commander Shabir Hussain is before an employment tribunal: he alleges he was passed over four times for promotion because of the colour of his skin.

He claimed last week that his career suffered while those of Blair’s hand-picked “golden circle” of white officers were advanced. Hussain said this was because he was Asian and not one of the commissioner’s “favourite sons and daughters”.

On Friday, after a second meeting with Ghaffur, Blair issued a statement saying he was trying to resolve the crisis. Like Ghaffur, he knows the racist card is the most powerful charge that can be levelled against the Met’s politically correct commissioner, who has sought to get rid of its image of being “institutionally racist”.

Blair’s rows

The spat with Tarique Ghaffur is the latest in a series of rows that Sir Ian Blair has had with his top team since he became Met chief in 2005

— He argued with his deputy, Paul Stephenson, above, last year after Stephenson told him it would be inappropriate to seek a £25,000 bonus while the Met was on trial over the killing of Jean Charles de Menezes

— The de Menezes case also led Blair to feud with Andy Hayman, then head of counter-terrorism. Hayman failed to tell Blair promptly that police had shot an innocent man, leaving the commissioner to make misleading statements suggesting that a terrorist had been killed. Feeling he had been “hung out to dry” in the inquiry into the fi asco, Hayman later resigned after news leaked of an inquiry into his expenses

— The Stockwell shooting also led Blair into a tiff with Brian Paddick, below, the Met’s most senior gay offi cer, who later ran for London mayor. Paddick challenged Blair’s claim that he did not know until the day after the shooting that his offi cers had killed an innocent man. Blair responded by, in effect, accusing Paddick of lying

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