Lance Armstrong is now in trouble with the U.S. government.
The Justice Department has joined a lawsuit filed two years ago by another disgraced cyclist, Floyd Landis, MSNBC.com was first to report on Friday.
The government could claim that it was defrauded by Armstrong, who denied using performing enhancing drugs while riding for the U.S. Postal Service team in the Tour de France but has since admitted to cheating in such a manner.
The government, which has a strict ban on illegal drugs, paid at least $30 million to sponsor Armstrong's racing teams.
But Armstrong could claim his contract with the team did not specify a ban on blood doping and that he did not sign a direct agreement with the U.S. Postal Service prohibiting the practice.