The center's executive director, Madgelean Bush (no relation to George W. Bush), had told Salon News and others that Bush did not do community service there, and the Bush campaign likewise denied the allegation.

But the Texas governor had admitted to working at Houston's Project P.U.L.L. in 1972, and Hatfield says he began to wonder if that was actually the community service sentence.

Hatfield says he confirmed those suspicions with three sources close to the Bush family he had cultivated while writing his biography, which publishes Wednesday.

Bush's campaign denied Hatfield's allegation Monday.

By contrast, "First Son: George W. Bush and the Family Dynasty," by Dallas Morning News reporter Bill Minutaglio, says George Bush Sr. referred his son to Project P.U.L.L. after an incident in which George W. drove drunk with his younger brother Marvin in the car.

But Hatfield quotes "a high-ranking advisor to Bush" who confirmed that Bush was arrested for cocaine possession in Houston in 1972, and had the record expunged by a judge who was "a fellow Republican and elected official" who helped Bush get off "with a little community service at a minority youth center instead of having to pick cotton on a Texas prison farm."

Hatfield quotes a former Yale classmate who told him: "George W. was arrested for possession of cocaine in 1972, but due to his father's connections, the entire record was expunged by a state judge whom the older Bush helped get elected.

It was one of those 'behind closed doors in the judges' chambers' kind of thing between the old man and one of his Texas cronies who owed him a favor ... There's only a handful of us that know the truth."

Another source named only as "a longtime Bush friend" described the situation this way: "Say you get a D in algebra ... and now you're going to be required to repeat the class the following year, but your teacher says if you promise to be tutored during the summer by a friend of hers who's good in math, she'll change the D to a C.

You spend a few hours a week during the summer vacation learning all about arithmetical operations and relationships, and then the teacher issues you a new report card, replacing the old one on file in the principal's office ... Something akin to that scenario is what happened with Bush in 1972."

Hatfield also says that when he asked Scott McClellan to comment on the allegation of a former Yale classmate of Bush's that the presidential hopeful was arrested for cocaine possession in 1972 and had his record expunged in exchange for community service at Project P.U.L.L., the Bush campaign spokesman said, sotto voce, "Oh, shit," followed by, "No comment."

McClellan denies that the exchange ever occurred. "I never spoke to the guy, and I'm not aware that anyone at the campaign has spoken to him," he told Salon News.