Questions surfaced even as Armstrong was on his way to his first Tour victory. He was leading the 1999 race when a trace amount of a banned anti-inflammatory corticosteroid was found in his urine; cycling officials said he was authorized to use a small amount of a cream to treat saddle sores.
After Armstrong's second victory in 2000, French judicial officials investigated his Postal Service team for drug use. That investigation ended with no charges, but the allegations kept coming.
Others close to Armstrong were caught up in the investigations, too: Bruyneel, the coach of Armstrong's teams, and three members of the medical staff and a consultant were also charged. Bruyneel is taking his case to arbitration, while two medical team staffers and consulting doctor Michele Ferrari didn't formally contest the charges and were issued lifetime bans by USADA. Ferrari later said he was innocent.
Armstrong was criticized for his relationship with Ferrari, who was banned by Italian authorities over doping charges in 2002. Former personal and team assistants accused Armstrong of having steroids in an apartment in Spain and disposing of syringes that were used for injections.
In 2004, a Dallas-based promotions company initially refused to pay him a $5 million bonus for winning his sixth Tour de France because it wanted to investigate allegations raised by media in Europe. Testimony in that case included former teammate Frankie Andreu and his wife, Betsy, saying Armstrong told doctors during his 1996 cancer treatments that he had taken a cornucopia of steroids and performance-enhancing drugs.
Two books published in Europe, "L.A. Confidential" and "L.A. Official," also raised doping allegations and, in 2005, French magazine L'Equipe reported that retested urine samples from the 1999 Tour showed EPO use.
Armstrong fought every accusation with denials and, in some cases, lawsuits against media outlets that reported them.
He retired in 2005 and almost immediately considered a comeback before deciding to stay on the sidelines — in part because he didn't want to keep answering doping questions. Three years later, Armstrong was 36 and itching to ride again. He came back to finish third in the 2009 Tour de France.
Armstrong raced again in 2010 under the cloud of the federal investigation. Early last year, he quit for good, making a brief return as a triathlete until the USADA investigation shut him down.
"He had a right to contest the charges," WADA President John Fahey said after Armstrong's announcement. "He chose not to. The simple fact is that his refusal to examine the evidence means the charges had substance in them."
AP National Writer Eddie Pells and AP Sports Writer Dennis Passa contributed to this report.
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