David Cameron accused of drug-taking, sexual promiscuity and an obscene act with a pig - but how much of it is true?

From allegations of drug-taking, sexual promiscuity and even a lurid tale of an obscene act with a pig, Lord Ashcroft’s biography of David Cameron does not pull its punches.

But what is true, what is speculation and how much is just an old political friend turned vehement foe, wreaking very public revenge?

Cameron’s drug-taking

One of the few close Oxford contemporaries that Lord Ashcroft persuaded to speak “on the record” about Cameron’s time at Oxford is the maverick journalist James Delingpole. In the book Delingpole recounts a tale of weed-smoking sessions in his college rooms along with Cameron and another friend, James Fergusson.

“My drug of choice was weed [cannabis] – and I smoked weed with Dave because James’s drug of choice was also weed,” Delingpole says.

“So he and James would come round to my room and the three of us would listen to Supertramp albums. I had a room on the top floor, and we’d all sit on the floor and smoke dope.”

In the run-up to the book’s publication many suspected that Ashcroft might have uncovered evidence that Cameron had also taken cocaine.

But, despite his best efforts, Ashcroft has failed to come up with any hard evidence. What is left is decidedly secondhand allegations dating from Cameron’s twenties and thirties.

“We have spoken to one member of his social circle,” Ashcroft writes, “who recalls the drug being in open circulation at a dinner party in the Camerons’ home.

“This guest did not see either Cameron or his wife take the drug, but the fact those present felt comfortable snorting it under their roof suggests it was not an unfamiliar scene.”

Drug policy U-turns

Ashcroft reveals how Cameron had a close relative who was addicted to a class-A drug. He also claims that when Cameron was a young MP, the relative’s partner acted as a drugs mule and collapsed and died in an Argentinian airport when bags of narcotics burst in their stomach.

He says this had a profound effect on Cameron – who as a member of the Home Affairs Select Committee argued for a more liberal drugs policy.

The book questions why Cameron appeared to have changed his position.

“Since becoming PM, he’s been in a position to implement all the sweeping reforms he wanted back in 2002 – yet he’s chosen not to do so,” Ashcroft writes.

When a more recent Home Office report on drugs policy recommended relaxing the law, Cameron rejected the findings outright.

The incident with a pig

This is one of the most bizarre passages from the book released so far – and the one which attracted most of the attention yesterday.

Ashcroft writes: “[Cameron] also got involved in the notorious Oxford dining society, the Piers Gaveston, which specialises in bizarre rituals and sexual excess.

“A distinguished Oxford contemporary claims Cameron once took part in an outrageous initiation ceremony involving a dead pig. His extraordinary suggestion is that the future PM inserted a private part of his anatomy into the animal’s mouth.”

Ashcroft said the source was an MP who first made the allegation at a business dinner in June 2014 – saying he had seen photographic evidence of the “disgusting ritual”.

Ashcroft said he is aware that the MP made the allegation on two separate occasions, providing more detail, including “the dimensions of the alleged photograph” and the “name of the individual who he claims has it in his keeping”.

Ashcroft said the owner “failed to respond” to their approaches but concluded it is “an elaborate story for an otherwise credible figure to invent”.

The hunt is on to identify the MP and track down the photo. But some people who were at Oxford at the same time as Cameron have considerable scepticism about its veracity.

Journalist Toby Young, who knew Cameron at Oxford and wrote about the Piers Gaveston Society for Vanity Fair in 1995, said he did not believe it to be true.

“I may not be the world’s foremost investigative journalist, but if anything like this had happened I think I would have heard about it,” he said.

Cameron is understood to have told friends that the claims are “utter nonsense” and that he was never a member of the society.

Womanising

The serialisation also dwells on Cameron’s Lothario tendencies at Oxford, claiming he enjoyed “nights on the pull – a recreation he apparently called ‘wooding’ – at a club called Playpen”.

Ashcroft quotes an anonymous contemporary, whose room was across the corridor from his at Brasenose College, recalling “a conveyor belt of pretty girls coming in and out of his room”.

“Living next to him, I was quite jealous. Most people were, I imagine. I think he slept with all the good-looking girls from college,” he recalls.

Lord Ashcroft’s non-dom status

In a foreword to the book Lord Ashcroft admits that one of the reasons he chose to pursue the project was because of a feeling of personal betrayal.

The peer was one of the Tories’ biggest donors – but also a controversial figure because of his wealth and suggestions that he was a non-dom – a status that allowed him to avoid paying tax on all his income despite being a Tory peer. Ashcroft reveals in the book that Cameron was well aware of his status in 2009 but recounts that “we had a conversation about how we could delay revealing my tax arrangements until after the election [in 2010]”.

Lord Ashcroft also claims Cameron reneged on a promise of a significant job should the Tories get into power. He says Cameron phoned him after the 2010 election to apologise and claim that the plan had been blocked by Nick Clegg.