She then confronted Mr. Frey about his fabrications, leading him to admit that in addition to exaggerating the amount of time he had spent in jail, he had lied about how his girlfriend had died; about the details of a foray outside a rehabilitation center; and about his claim that he had received a root canal without anesthesia because the center prohibited the use of Novocaine.

"I think most of what they wrote was pretty accurate, absolutely," Mr. Frey said yesterday of the Smoking Gun report.

Ms. Winfrey also acknowledged that she had received an early warning that parts of "A Million Little Pieces" were fictionalized from a former counselor at the center where the book takes place. Eight days after she picked the book in September, a former counselor at Hazelden, the Minnesota treatment center now identified as the one where Mr. Frey stayed, contacted her producers and told them that many parts of the book were untrue.

Ms. Winfrey said that she had had her producers ask the publisher about the allegations, but that they were reassured the book was accurate. She had harsh words during the broadcast for the publisher, Ms. Talese, who said that neither she nor anyone at Doubleday had investigated the accuracy of Mr. Frey's book. She said the company first learned that parts of the book had been made up when The Smoking Gun published its report, nearly two years after the memoir was first published.

"An author brings his book in and says that it is true, it is accurate, it is his own," Ms. Talese said. "I thought, as a publisher, this is James's memory of the hell he went through and I believed it."

But Ms. Winfrey pointed out that her producers had asked about reports of the book's truth in September, after the Hazelden counselor raised doubts, and that they were reassured by Random House.

"We asked if you, your company, stood behind James's book as a work of nonfiction at the time, and they said absolutely," Ms. Winfrey said. "And they were also asked if their legal department had checked out the book, and they said yes. So in a press release sent out for the book in 2004 by your company, the book was described as brutally honest and an altering look at  at addiction. So how can you say that if you haven't checked it to be sure?"