Random House is standing by author James Frey in spite of mounting controversy over the veracity of his best-selling memoir.

Mr Frey’s book, A Million Little Pieces, recounts in visceral detail the author’s battles with drugs and alcohol. After winning the influential endorsement of television host Oprah Winfrey, it sold more copies in the US last year than all but Harry Potter.

However, Mr Frey’s account has come under fire from website The Smoking Gun, which has compared the author’s account of his outlandish behavior to police reports and other source materials, and claims much of it has been fictionalised or exaggerated.

Mr Frey, for example, claimed to have spent three months in prison after striking a police officer with his car and inciting a riot. However, police records checked by The Smoking Gun, which is owned by Court TV, reveal that Mr Frey spent no time in prison for the incident, and that he had merely been found asleep in his car.

“We’re standing by our author,” a company spokesperson said.

A statement released by Doubleday, a Random House division, was more nuanced. It noted that memoir was “highly personal” and said that Mr Frey had represented to the publisher that the story was “true to his recollections.”

The controversy has focused attention on the memoir. It has become one of the best-selling categories in the book publishing industry in recent years. However, standards for accuracy are not as rigorous as they are in other sectors of the print media, such as newspapers and magazines.

A Million Little Pieces has also come under question at a time when another US literary celebrity, JT LeRoy, has been unmasked as a hoax.

On his website, Mr Frey dismissed the accusations. “This is the latest investigation into my past, and the latest attempt to discredit me,” he wrote. The author was due on Wednesday night to appear on Larry King Live.

Meanwhile, Random House denied reports that it had offered special refunds to customers who bought A Million Little Pieces. “It has long been standard Random House Inc procedure to direct consumers who want a refund on any of the tens of thousands of books we publish back to their retail place of purchase,” the company said, noting that it had received only 15 calls about the book on Tuesday, and fewer on Wednesday.