Criminal investigation unlikely

Legal experts said it was unlikely US prosecutors would reopen a criminal investigation into Armstrong which was closed earlier this year and if they did it was even less likely he would end up behind bars.

The Department of Justice in Washington and the US Attorney's in Los Angeles declined to comment but Geoffrey Rapp, a law professor at the University of Toledo's law school, said: "I don't see Armstrong going to jail."

Despite agreeing that Armstrong cheated his way to the top, USADA and UCI continued to trade thinly veiled insults on Monday.

International Cycling Union (UCI) president Pat McQuaid arrives for a news conference on the Lance Armstrong doping scandal in Geneva Oct 22, 2012. [Photo/Agencies]

McQuaid said USADA should have handed over its evidence to a neutral investigator and said anti-doping agencies needed to share the blame because their tests failed to catch him.

USADA responded by saying the UCI's banning of Armstrong was not the end of the problem because USADA's investigation showed that doping was rife in professional cycling.

"There are many more details of doping that are hidden, many more doping doctors, and corrupt team directors and the omerta (code of silence) has not yet been fully broken."

On Oct 10, USADA published a report into Armstrong which alleged the now-retired rider had been involved in the "most sophisticated, professionalized and successful doping program that sport has ever seen".

Armstrong, 41, had previously elected not to contest USADA charges, prompting USADA to propose his punishment pending confirmation from cycling's world governing body.  

Former Armstrong teammates at his US Postal and Discovery Channel outfits, where he won his seven successive Tour titles from 1999 to 2005, testified against him and themselves and were given reduced bans by the American authorities.

"It wasn't until the intervention of federal agents...they called these riders in and they put down a gun and badge on the table in front of them and said 'you're now facing a grand jury you must tell the truth' that those riders broke down," McQuaid added.

Armstrong, widely accepted as one of the greatest cyclists of all time given he fought back from cancer to dominate the sport, has always denied doping and says he has never failed a doping test.

He said he had stopped contesting the charges after years of probes and rumours because "there comes a point in every man's life when he has to say, 'Enough is enough'".