Lance Armstrong's fight with U.S. anti-doping officials is going before a federal judge in Austin, Texas.
The U.S. Anti-Doping Agency says Armstrong used steroids and blood boosters to win the Tour de France from 1999-2005. He faces a lifetime ban from the sport and could be stripped of his titles if found guilty.
Armstrong denies doping and is suing to block the case. His lawyers will argue in court today that the doping agency's investigation and arbitration process are unfair and violate his constitutional rights.
Armstrong also says the International Cycling Union should have jurisdiction.