Lance Armstrong's lawyer has described the investigation into the seven-time Tour de France winner as "unAmerican" and a waste of money in the wake of fresh claims against the cyclist in the US media.
A report in the New York Times from an unnamed former team-mate of Armstrong's on the United States Postal Service, claimed that doping on the team was widespread and carried out with Armstrong's "knowledge and encouragement".
"This is a story full of anonymous sources and more inappropriate leaks of grand jury testimony designed to create a circus-like atmosphere," Armstrong's attorney, Brian Daly, said in a statement. "The power of the federal government is being abused to pursue dated and discredited allegations, and that's flat-out wrong, unethical, unAmerican, and a waste of taxpayer dollars.
"To the extent that any riders are suggesting that Lance Armstrong violated cycling rules or doped, they are either mistaken or not telling the truth. Lance has ridden with hundreds of riders who will support his position, and over all that time he has never failed even a single test."
A grand jury has been convened in Los Angeles following allegations made by former US Postal Service rider Floyd Landis. Landis, who was stripped of his 2006 Tour title after a positive dope test, accused Armstrong and several other American riders of using performance-enhancing drugs.
Armstrong has repeatedly denied any wrongdoing. The American was diagnosed with testicular cancer before going on to win seven successive Tours from 1999-2005.