The Orioles star gave a lengthy statement to the arbitration panel, but those familiar with the record say he did not account for how he tested positive, becoming the highest-profile baseball player suspended for use of a performance-enhancing drug.
The sources, who were interviewed on condition of anonymity, said they want to wait until Congress finishes its review before speaking publicly. Palmeiro has given the same reason.
Palmeiro has suggested through his agent, Arn Tellem, that as-yet-undisclosed information would cast the positive drug test in a different light.
Palmeiro may yet provide an explanation. But if he has details about how the steroid, stanozolol, entered his system, it is unclear why he didn't provide them during the critical defense before baseball's three-member arbitration panel. Major League Baseball won't say exactly when the hearing took place.
Palmeiro's public comments have been vague. He said in an Aug. 1 conference call that he never intentionally put a banned substance into his body and that "I would love to tell what happened so everyone would understand."
While it is possible that Palmeiro might not know how the steroid got into his body, experts have discounted the possibility that stanozolol could have entered his system accidentally.
Neither Palmeiro nor Tellem could be reached for comment yesterday.
Palmeiro, 40, returned from his 10-day suspension on Aug. 11 but was not immediately placed in the Orioles lineup. He received a mixed greeting from home fans on his return to the field on Sunday.
Palmeiro tested positive in the spring as he pursued his milestone 3,000th hit and challenged the result with baseball's four-person Health Policy Advisory Committee, which oversees baseball's drug testing program. He then won the right to plead his case - which he eventually lost - before the arbitration panel, consisting of an MLB lawyer, a union lawyer and an independent arbitrator.
The record of the panel's hearing was part of a number of documents that Major League Baseball recently turned over to the House Government Reform Committee, which wants to know whether Palmeiro lied when he testified at a March 17 hearing that he had never used steroids. The commissioner's office has copies of the hearing record, as do Palmeiro's representatives.
One member of the Government Reform Committee, Baltimore Democrat Elijah E. Cummings, says he believes Palmeiro should provide an explanation to fans. "I think he owes a debt of straightforwardness," Cummings said recently.
Members of the House Energy and Commerce Committee are also studying Palmeiro's case. Reps. Cliff Stearns, a Florida Republican, and Joe L. Barton, a Texas Republican, recently requested a timeline from the commissioner's office of the arbitration process, among other documents, on Palmeiro's positive test.
The arbitration panel has only hinted at what happened at Palmeiro's hearing, saying in an Aug. 1 news release that the ballplayer had not met the burden of establishing that his positive test result was not his fault.
The panel added that Palmeiro's testimony "in many respects was quite compelling" and that there was no evidence that the ballplayer was "untruthful."
Palmeiro, a potential Hall of Famer, was accused in a book by former Texas Ranger teammate Jose Canseco of using steroids when the two played together in the early 1990s. Palmeiro has denied the accusation contained in the book, which was released in February.