The credibility of the author who accused George W. Bush of having once been arrested on cocaine charges exploded yesterday.

James H. Hatfield is a felon who was convicted 11 years ago in a failed attempt to kill his ex-boss with a car bomb, according to an Arkansas parole officer. The news stunned his publisher, St. Martin's Press, which yesterday halted publication of the Bush biography, "Fortunate Son."

Hatfield denied to the Dallas Morning News that he has a criminal record, calling it a case of mistaken identity. But the parole officer, Eddie Cobb, told the paper that J.H. Hatfield the author, who previously wrote a biography of "Star Trek" actor Patrick Stewart, is the same man who remains on parole through 2003. Cobb confirmed the account yesterday to The Washington Post.

St. Martin's said it is halting all sales and promotional activity because the report, "if true, calls into serious question our continued ability to trust the information provided to us by Mr. Hatfield."

John Murphy, a St. Martin's spokesman, said the company has shipped 70,000 copies to stores and has 20,000 in storage. "Their future is up in the air," he said. Murphy said the firm's lawyers are "trying to get to the bottom of it" but did not know if they had questioned Hatfield.

The revelation is the latest bizarre twist in the media's handling of a charge, based on three anonymous sources, that lacks any independent corroboration. Bush's presidential campaign flatly denies that the Texas governor was arrested in 1972 or that a judge expunged the record in exchange for Bush performing community service, as Hatfield claims.

Campaign spokeswoman Mindy Tucker declined to discuss Hatfield's past but said: "He should have stuck with science fiction. He's obviously trying to sell books by peddling something that's false and untrue."

In his impassioned denial to the Morning News, Hatfield said: "Doesn't it sound a little bit weird to you that all of a sudden, the guy that's accusing potentially the next president of the United States of having his record expunged, all of a sudden miraculously has a record himself in the state of Texas? This is just a little bit too bizarre."

The Morning News said the author and the convicted Hatfield shared the same month and year of birth, lived in Dallas at the same time and now live in the same area of Arkansas. Asked to distinguish himself from the man who was imprisoned, Hatfield refused to tell the paper his date of birth or where he worked during the period of the prison sentence.

James Howard Hatfield pleaded guilty in 1988 to paying another man $5,000 to bomb the car of a manager at a financial firm he had recently quit, according to Dallas court records cited by the Morning News. The bomb had exploded in the parking lot of Dallas's Cotton Exchange Building the previous year, but the two people in the car were not injured. Hatfield served five years of a 15-year prison sentence and was paroled in 1993.

The online magazine Salon reported yesterday that editors of several Texas publications that Hatfield purports to have written for said they were unaware of him, and that there was no evidence that a literary award claimed by Hatfield actually exists.

Even before the questions about Hatfield's past, the media world was split over how to handle the Texas writer's allegation against Bush, which appears in a hastily added afterword.

Over the summer, the press focused intensively on the governor's refusal to say whether he had ever used cocaine and his subsequent statement that he has used no illegal drugs since 1974. Hatfield's book was the first suggestion of a cocaine arrest--although he fails to supply the date or location of the supposed arrest and the name of the judge who is said to have expunged the record.

Hatfield writes that when he called the Bush campaign with his allegations, spokesman Scott McClellan refused to comment. McClellan says he's never spoken to Hatfield, according to Tucker of the Bush campaign.

Salon and the Drudge Report were the first to publicize Hatfield's allegations. In fact, Salon helped put the story in play. Hatfield writes that he began investigating after an August gossip column in Salon reported a widely circulated e-mail claiming that a Texas judge had ordered Bush to perform community service "in exchange for expunging his record showing illicit drug use." Columnist Amy Reiter quoted the head of the Houston community center as denying that Bush had served there.

Asked about its story this week on the Hatfield book, David Weir, Salon's senior vice president, said: "Salon, and the Internet generally, aren't really interested in the corporate-gatekeeper mode of deciding about stories. When a major publisher releases a book . . . we're going to be all over it. On the Internet, you get the information out there and your readers help you evaluate it."

Salon's initial report included the Bush camp's denials. "Covering it is not the same as endorsing it," Weir said. "We hardly endorsed this book." columnist Jacob Weisberg said he faced a "dilemma" while writing a piece denouncing the book.

"The evidence was far too thin for us to do a story," Weisberg said. "So do you report on someone else making an accusation that doesn't meet your standards? Sometimes that's the wrong thing to do and can be a sneaky, backdoor way of getting it into play. But when you're debunking an accusation, it's a necessary part of holding the media accountable."

Weisberg got a startling admission out of Hatfield when he asked about a passage quoting Unnamed Source No. 3, describing him as "pausing occasionally to spit tobacco juice into the ever-present Styrofoam cup."

How could Hatfield have known that if he was, as he said, talking to the source by phone? After saying he had seen the man spit tobacco in the past, according to Weisberg's piece Hatfield acknowledged: "I might have put that in to protect him. He doesn't chew tobacco--I had to help him out a bit."

The book never makes clear why the three Bush supporters would share the damaging information with Hatfield. The source who is described as chewing tobacco is quoted at length and in dramatic fashion:

"W. got caught with cocaine in 1972 and because his daddy was oil rich and influential in Harris County politics, he got his son off with a little community service at a minority youth center instead of having to pick cotton on a Texas prison farm. . . . I personally advised him to stay on course and never admit anything. . . . Be careful and watch your back every step of the way. Without sounding paranoid, I think I would be amiss if I didn't remind you that George's old man was once director of the CIA."

Most major newspapers initially ignored the Hatfield book, although the New York Post and Washington Times ran brief stories about it. On Wednesday, the Boston Globe, Washington Post, Houston Chronicle, Atlanta Constitution and Associated Press, among others, ran articles or items about the book after former president George Bush issued a statement denouncing the charges as "mindless garbage" and a "vicious lie." He denied ever intervening with a judge on the younger Bush's behalf, saying Hatfield "has insulted our son's character and my character and I resent it."

Stephen Hess, a presidential scholar at the Brookings Institution, criticized the handling of the story. "The problem is that mainstream, distinguished publishers aren't checking these things," he said. "They aren't in the business of fact-checking." As for newspapers, "you wind up publishing a story because someone denies it, which strikes me as a pretty shabby ethic."