In the end, it was neither the allegations that hundreds of thousands of pounds of taxpayers' money had been given improperly to projects (denied). Nor the allegation that trips abroad were not properly declared (denied).

The final straw for Lee Jasper, after two decades as Ken Livingstone's left-hand man, was the e-mails informing Karen Chouhan, a community project worker, of his unbridled passion for her “feet, ankles, legs, thighs, bum and belly, arms, head and brain”. His feelings were particularly strong during “the first gentle dew on a golden summer morn”.

Ten hours after their publication, “General Jasper” as he signed the e-mails, quit his £120,000-a-year job at City Hall. Jasper has not been found guilty of any crime, nor judged to have broken any rules and has repeatedly suggested that the media stories against him are part of a racist campaign.

But the allegations involving Chouhan are potentially radioactive because in 2005 he was involved in the decision to approve a £100,000 grant to the 1990 Trust, of which she is the secretary. The code of ethics requires Livingstone's staff to disclose any “close personal relationship” with anyone involved in a working situation. Opponents say this fits into a wider pattern of behaviour, which they allege suggests cronyism, perhaps corruption. Reports in the Evening Standard have alleged a group of Jasper's friends and business associates have benefited from more than £2 million in public grants to community organisations that either went bust or provided little public benefit.

Jasper, 49, was brought up in Oldham by his white mother. His father was Jamaican. In his twenties, with a degree in social sciences, he moved to London and became involved in the Notting Hill Carnival.

Over the next decade Jasper established himself as a race-relations activist and led the National Black Alliance, National Black Caucus, Operation Black Vote and the National Assembly Against Racism after the Stephen Lawrence inquiry made the charge that London's police force was “institutionally racist”.

In 1995 he was involved in controversy when riots broke out after his “very, very angry” speech at a protest in Brixton over a death in police custody. An investigation cleared him of incitement. Within a few months he was being paid £500 a day by the Home Office to lecture police on race relations. After Livingstone was elected as Mayor of London in 2000, Jasper became his senior adviser on race relations and police.

Even Jasper's housing arrangement has raised eyebrows. He lives in state-subsidised social housing, paying around £90 a week for a four-bedroom house in Clapham.

As he grew in influence, he also grew in size: 18st last year. But he has slimmed down recently, saying that he needs energy for his nine children and four grandchildren.

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