For once, the hype was real. Frey's book, A Million Little Pieces, a splenetic, repetitive, punctuation-shy memoir of his drug and crime-filled youth was a huge success. The fall and rehabilitation of the man with ten tattoos - one of which reads "F.T.B.S.I.T.T.T.D" or "F**k The Bullshit It's Time To Throw Down" - was optioned by Warner Brothers and Frey was invited on chatshows.

Last September, Frey won the gold prize of American massmarket literature when A Million Little Pieces was chosen by Oprah Winfrey as the autumn read for her book club. Oprah justified her first ever non-fiction choice, hewn almost entirely of profanities, vomit and drugs, because it was "raw and so real". Powered by a one-hour appearance on Ophrah, Frey's sales erupted, taking A Million Little Pieces to second in the bestseller lists behind Harry Potter and the Half Blood Prince.

By this point, Frey was winning fans in the UK. On the publication of My Friend Leonard, a sequel to A Million Little Pieces, last year, Frey was interviewed by The Times and praised for his integrity. But the big draw was still his first book, with its brutal, straight prose - "I want to get f**ked up. I want to get f**ked up. I want to get f**ked up" - is a fairly representative sentence.

The UK edition of the book, published by John Murray, is littered with positive reviews: "Turbocharged", said the Independent. The Observer went further. "As a memoir," it wrote. "It is almost mythic."

Almost mythic, it turns out, was right. Last Sunday morning, after six weeks of careful drudgery, The Smoking Gun, an American investigative website best known for its mugshots of arrested celebrities, published a 13,000 word article about A Million Little Pieces which opened with the words: "Oprah, you've been had."

Using public records, interviews with police and old classmates, The Smoking Gun questioned Frey's version of several formative events in his life. The first was the death of Frey's only school friend, "Michelle", in a train crash one night after she met him at the cinema. Police records showed no contact with Frey that night and the parents of Melissa Sanders, the girl who died in the accident, said Frey, three years below Sanders in high school, might have sent a condolence card but was not a close friend.

A second incident, what Frey described as an FBI investigation of his drug dealing at college, turned out to be a local police inquiry. "We're not talking Detroit here," a policeman told the website. "It's like Billy and Buffy saying, 'I think we should steal a stop sign.'"

The third case examined by The Smoking Gun overshadows the entire book. The looming consequences of a night of Ohio madness is the structural device that ends it, starts the sequel and contributes to the suicide of Frey's girlfriend, Lilly, who he meets in rehab.

In A Million Little Pieces, Frey recounts how drunk, high on crack and desperate to meet an old girlfriend, he ran over a policeman and tried to start a riot: "I said you want me out, then get me out, you f**king Pigs. They opened the door, I started swinging, and they beat my ass with billy clubs," he wrote.

Frey's attack leads to him being charged with a miscellany of serious crimes, including "felony mayhem". After being threatened with eight-and-a-half years in jail, "most likely… maximum security", Frey is eventually offered a three-month sentence in a county prison. Frey serves the time only, in the opening pages of My Friend Leonard, to find that his girlfriend has committed suicide on the day of his release.

The Smoking Gun described the arrest in markedly different terms. According to records found in the basement of the Granville Police Department, in Licking County, Ohio, Frey was arrested while drunkenly trying to park his car outside a pizza restaurant. He was cautioned for driving without a licence and under the influence and fined $733. He spent a total of five hours in custody and was described as "polite and co-operative at all times". There is no such crime as "felony mayhem" in Ohio.

The allegations, which do not question Frey's addiction to drugs and his recovery, carried extra intrigue because of the author's own attitude towards the truth.

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