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Andrew Gilligan: My war with Ken Livingstone

Four years after Lord Hutton publicly castigated Andrew Gilligan for his flawed reporting methods, the journalist is again in the spotlight having locked horns with the Mayor of London. He tells Ian Burrell how he has rebuilt his career

"It didn't damage my reputation long term and it didn't damage my employment prospects," says Andrew Gilligan, matter-of-factly reflecting on the lasting effects of Lord Hutton's inquisition into the standards of his journalism – a gruelling ordeal that might have left others in this profession mentally broken and fleeing in search of an alternative existence in the faraway hills.

Yet here is, right back in the fray. Having fought his desperate and very public battle with Alastair Campbell over the Government dossier justifying war in Iraq, Gilligan is now engaged mano a mano with another of the great media-savvy political figures of our times, Ken Livingstone. Once again, it has been a dirty, highly personal fight, with the Mayor of London calling for the journalist to be fired and citing Hutton as proof of the reporter's flawed methods.

Gilligan has his shoes off and his feet up on a white armchair in the living room of his London apartment. In spite of blue skies and sunshine outside, a gas fire with convincing flames is blazing away cosily and the bookshelves behind him groan with a library of political biography and tomes that analyse the workings of the fourth estate. He seems relaxed, apparently convinced his investigation into the Mayor's office is fireproof.

He is wary enough, however, to take the precaution of placing his own tape recorder on a small table, where it sits alongside a pile of documents from the London Development Agency, the Mayor-run organisation that has been the main focus of his investigation for the London Evening Standard. The Hutton inquiry famously exposed Gilligan's unorthodox interviewing technique, using a personal organiser to record notes of answers given by his source, the Government weapons inspector Dr David Kelly; it seems he has learned to be more meticulous.

His calm demeanour is a direct consequence of what he went through with Hutton and Campbell. "Nothing will ever be as bad as the pressure over Hutton," he says. Though the Livingstone investigation is "probably the biggest story I've done since then", the stress levels are "nothing like as bad".

In planning this investigation, Gilligan, 39, drew heavily on the experience of the dossier story. "My response to this was informed at all stages by what happened over David Kelly," he says. "The lesson I learned from Hutton was that anonymous sources, however accurate – and Kelly was accurate – are not enough, because they can be pressured. Ultimately, you have to have pieces of paper that you can show people. So this story is rested on Companies House records and documents, leaked emails and letters and the testimony, on the record mostly, of whistle-blowers."

His approach has been that of a chess player, planning several steps ahead and trying to anticipate the responses of the Mayor to the Evening Standard's stories. So after spending more than four weeks investigating a network of 11 companies and organisations, linked to Livingstone's race adviser Lee Jasper, that were in receipt of around £2.5m in public money but allegedly did little for it, Gilligan deliberately held back large amounts of material from his initial report.

"One of the most important things in this is to plan for the counterattack, because this is an extremely damaging story to Livingstone. We knew he would say it was all lies and there would be the inevitable dash of Lord Hutton thrown in. We held quite a lot of our evidence back. He's not a cautious politician, and we knew he would shoot his mouth off straight away. And then we rolled out more of our other evidence. He fell right into the trap in an absolutely amazing way."

The Mayor responded to the Standard's accusations by quoting Hutton's comment that "I have considerable doubt as to how reliable Gilligan's evidence really is" and insinuating that the stories were politically motivated and racist.

"In some ways, Livingstone's response has been more damaging than the allegations, because it has been so unpleasant, so transparently dishonest and so arrogant. The clear impression has come across of a man who doesn't believe he should be held to account and doesn't want to answer straightforward factual questions. I was perfectly happy for him to pile in and say I was a liar and a murderer, because they are ludicrous charges."

With remarkable confidence, Gilligan says that "everyone in the country, or the overwhelming majority, believes I broadly got it right over the dossier – and I did get it right broadly. I mean, I never denied I made some mistakes in the detail, but I won that argument long ago, and if Livingstone wants to reopen that he's got no chance."

The Standard has been at war with Livingstone almost from the moment Veronica Wadley became editor six years ago. Gilligan rejects the idea that he is Wadley's attack dog, unleashed ahead of an election.

"Veronica has never told me to do a story about Ken," he says. "We don't start every day in the bunker with Veronica stroking a white cat going: 'Today you will destroy Ken Livingstone.' It's just not like that. Are they saying an election is an inappropriate time to examine the mayor's activities and those of his senior advisors? It's ridiculous."

Gilligan has kept his investigation going with further revelations over three months. The stories have undoubtedly helped Boris Johnson, the Conservative mayoral candidate and former editor of The Spectator, who is said by one recent poll to have a narrow lead over Livingstone. When Gilligan is asked who in the media was most helpful at the time of Hutton, the name "Boris Johnson" is the first out of his mouth. "This is why I have been accused of being pro-Boris. Boris gave me some work on The Spectator. He was very supportive over the whole thing and I've made no secret that I'm very grateful for that."

Some of those who regard the Standard's campaign as a Tory conspiracy would be surprised to hear Gilligan describing himself as "of the left", though he also says that "Boris believes in liberty and I'm on the left but I'm a libertarian".

Asked if he would see a Johnson victory as a vindication of his investigations, he says, "No, journalists don't... it's up to the public. We are just doing what journalists should do, which is holding people in power to account. I will do exactly the same to Boris if he becomes mayor."

Gilligan does what a lot of journalists don't do: stay up all night at his computer trawling through public documents for stories. "Quite a lot of stories don't come from brown envelopes and people in car parks, they come from quite boring places that are available for anyone to see if they wanted to," he says. His current investigation began when he was looking online at Livingstone's answers to members of the London Assembly. His suspicions were aroused by an organisation called Brixton Base that had been in receipt of public money but did not appear to pay rent, and he began retrieving records from the Companies House website.

"It's one of the great indictments of journalism that so few people do it. It's not that hard. One of the striking things about this story was that it actually was in relatively plain view. The payments to these companies are a matter of public record, if you know where to look and you want to sit there with your calculator and add it all up."

Gilligan, who rarely goes into the office, says the internet "has transformed my productivity, and made it a lot quicker to do investigative journalism". He rejects some arguments that modern journalists are overstretched. But he does feel sympathy for local newspaper journalists, including some of those who report on the Mayor of London.

"Some of the owners of local newspapers are disgraceful," he says. "They make huge profits and they are greedy for even more. You've got quite reputable local newspapers being produced by 22-year-olds on 15 grand a year. That's hopeless. They haven't got time sometimes to make phone calls, let alone go out. That's poisoning the ecosystem of the whole of journalism.

"The problem for Livingstone is that until now, as Mayor, he's mostly operating without that much serious scrutiny. He's not a national politician, and is scrutinised by local newspaper journalists mostly. Then suddenly this comes along and it's very uncomfortable."

Another of his criticisms of other reporters is that they refrain from using their front-row seat to make judgments, preferring a bland neutrality. "You can try and get a bit closer than most journalists do. They think it's going out on a limb a bit, and it is I suppose, but they should do it more often." His comments recall an observation by BBC news chief Richard Sambrook that Gilligan "paints in primary colours" rather than "subtleties and nuances".

Gilligan's Standard allegations have all concerned black organisations, and the reporter has faced accusations of racism. He claims that some of his best tips have come from sources in black communities who are angry at the alleged cronyism. He also acknowledges anecdotal reports that his stories have caused collateral damage, with other black organisations suddenly treated with mistrust by public bodies. "I think there might be [collateral], yes, but I'm afraid it's not our job to think about consequences like that," he says. "A lot of black organisations are extremely happy about these stories because they think they might finally get some money."

"Racist", "liar", "murderer" – Gilligan has had it all. After Dr Kelly's suicide, The Sun ran the journalist's picture on the front page, under the headline "You rat". Gilligan says he has always had a fairly thick skin. "If The Sun was doing a piece saying I was the worst journalist in the universe, it never really bothered me, because I knew I wasn't and they were only doing it for political reasons because Murdoch wanted to stiff the BBC."

Though Gilligan, a former Sunday Telegraph defence writer, didn't anticipate returning to newspapers ("I thought I would stay at the BBC, to be honest – I really liked working for the BBC"), he is grateful that the Standard gave him another chance, as did Channel 4's investigative strand, Dispatches, for whom he makes two documentaries a series.

A Cambridge graduate, Gilligan has the inquiring mind, the bolshy determination and the tough hide (not to mention something of the appearance) of BBC political editor Nick Robinson. There's also a little bit of the nerdy comedian David Mitchell of Peep Show fame. Asked what he likes to do when he is not scouring PDF files of public documents late at night, he stalls. "Really, what do you mean, like personal interests? Walking and cinema and that kind of thing? One of the problems to be honest ... you know what it's like with journalists: you do get totally tied up in the work, and it becomes your whole life. Under Hutton I thought I'd make a conscious decision not to let it become my whole life."

And what happened?

"Well, I didn't manage it. It's one of many promises I've made to myself that I have never kept."