His doctors have all been caught and have received lifetime bans. They could testify against Armstrong, but what's the point if they couldn't save their own asses?
Anyway with 10 team-mates and even the make-up lady all willing to testify under oath, Armstrong knows his endgame's up. Better quit and leave an element of doubt than to go to arbitration and have all the sordid details dredged out.
http://abcnews.go.com/US/lance-arms...-banned-doping/story?id=16750719#.UDg_Ohy66sE
According to the U.S. Anti-Doping Agency (USADA), Dr. Luis Garcia del Moral, a cycling team doctor; Dr. Michele Ferrari, a cycling team consulting doctor; and Jose "Pepe" Martí Martí, a cycling team trainer, have all received lifetime bans as the result of anti-doping rule violations that occurred while they were working with Armstrong's former cycling teams.