In a report commissioned by professional cycling's international governing body, a Dutch lawyer dismissed those doping claims, saying in May that the test results were botched by a French lab and don't "constitute evidence of anything."
The Dutch report generated a furious controversy in the cycling world and added to public confusion over the Armstrong allegations.
At the same time, sports authorities now have the ability to make greater use of circumstantial evidence in pursuing doping-related inquiries. In a ruling in December, the Swiss-based Court of Arbitration for Sport, the final authority for many disputes in the international sports world, said it must "constantly be borne in mind
In a sign of how seriously Armstrong is taking disclosures in the arbitration case, the racer has launched a series of public appearances to vigorously deny that he has ever used illicit substances.
And Armstrong's attorneys e-mailed and sent by certified mail a subpoena seeking to compel disclosure of how The Times obtained access to the records. They also dismiss as "misleading or incorrect" aspects of the case files "leaked to the press in violation of the explicit orders issued by the Arbitration Tribunal."
The most extensive accusations against Armstrong contained in the Texas arbitration files revolve around allegations of EPO use.
In cycling, as in other endurance sports such as triathlon or marathon racing, oxygen equals power.
The science of getting oxygen to the muscles can prove, in practice, fantastically complex. Yet the underlying theory is simple: The more red blood cells inside the system, the more oxygen those cells can carry to the muscles -- and thus the harder an athlete can train, recover and race.
The kidneys produce the hormone erythropoietin. It tells bone marrow to make red blood cells.
Synthetic EPO is a biotech marvel created in the 1980s to treat anemia resulting from kidney failure or from cancer chemotherapy. It mimics the effects of naturally produced EPO and is thus banned by anti-doping authorities. Riders inject it, in the style of a diabetic injecting insulin.
By the fall of 1996, according to a 1998 letter sent to racers by an anti-doping executive of the International Cycling Union, "rumors and unease over the use of EPO assumed a vast scale. The theory was that the person who administered the most EPO injections could win the competition. An untenable situation," said the letter, filed in the case.
Armstrong was linked to EPO by former racing teammates who testified in the Texas arbitration. They described a 1995 bike ride in Italy during which they recalled talking about EPO's potential for making their Motorola team more competitive.
In a deposition, Stephen Swart testified that "one of the discussions there was about EPO and how we were still riding at such a disadvantage to the European teams and having to look seriously on how to rectify the problem."
Swart, a New Zealander, was asked, "What did Mr. Armstrong say?"
"Well, basically saying that ... you know, you have to do what you have to do," Swart responded.
Questioned about what he understood Armstrong's position to be on the use of EPO, Swart said, "You didn't have to be a rocket scientist to figure it out." He said his conclusion at the end of the ride with Armstrong was that "for us to be competitive at the Tour that year, that we needed to start a medical program of EPO."
Swart said he tried EPO himself in 1995 but testified that he stopped because it wasn't "working for me."
Regarding the same bike ride and alleged EPO discussions, a second teammate, Frankie Andreu, testified of "a general tone about ... stepping up, meaning in training and possibly maybe even participating, maybe taking EPO ... because there were many riders that were doing it."
Armstrong testified: "I was never party to that conversation. If it took place -- I'm not calling Frankie a liar, but there ... there are many other people he could have had that talk with."
Armstrong was also asked: "Did you begin an EPO program in 1995?"
"The answer is no," he testified.
According to Swart's deposition, he and his teammates -- including Armstrong -- had their blood tested during one of the mountain stages of the 1995 Tour. The team doctor, he said, was checking the riders' hematocrit level -- the percentage of red blood cells in the population.
Anything over 50% leads experts to suspect EPO use; a high hematocrit reading also prompts medical concerns because a dense concentration of red blood cells can turn the blood sluggish.
The cycling union would later impose a rule barring any rider with more than 50% from starting. But in 1995 there was no such rule.
His own hematocrit level, Swart said, was 47. Everyone else on the team recorded a level over 50, including Armstrong, Swart testified. The level for most males is about 42.