A former teammate, Floyd Landis, filed a whistleblower lawsuit against Lance Armstrong in 2010 under the federal False Claims Act related to the doping allegations that Armstrong admitted to last week. The lawsuit has been under seal (kept secret) since it was filed. It alleges that Armstrong defrauded the team sponsor, the United States Postal Service, by accepting some $30 million in federal money for a team illegally fueled by performance-enhancing drugs.
Landis himself was stripped of the 2006 Tour de France title based on a positive drug test.
Source: Washington Post
The False Claims Act dates from the Civil War when it was enacted to deter military contractors from defrauding the War Department by providing shoddy uniforms and other goods. The False Claims Act rewards whistleblowers by allowing them to retain 15-25% of the monies recovered from the federal government contractor that was defrauding the government.
A good article about the False Claims Act and the Lance Armstrong case can be found in Forbes.
