Lance Armstrong filed a scathing response Friday to the latest doping allegations against him, accusing the U.S. Anti-Doping Agency of violating its own rules and possibly breaking federal law during its investigation.

The agency said Armstrong used performance-enhancing drugs and other improper methods to win cycling's premiere event, the Tour de France, from 1999-2005. Friday was the deadline for Armstrong to respond to USADA's warning that charges were pending before his case moves to the next stage.

Armstrong, who denies doping and notes he has never failed a drug test, could be stripped of his titles and banned from cycling, though he retired from the sport last year.

In their 11-page document, Armstrong's attorneys complained they still haven't been allowed to see the evidence against him, including witness names and any expert analysis to support USADA's claim that 2009 and 2010 blood tests are "fully consistent" with blood doping.

The letter said USADA's case is "long on stale allegations disproved long ago and short on evidence" and "offensive to any notions of due process."

Armstrong's case now goes to a three-person USADA review board, which will decide if there is enough evidence to support the charges. If USADA files formal charges, the case could go to a three-person arbitration panel by November.

- Associated Press