The US Anti-Doping Agency has claimed that Lance Armstrong's decision not to be interviewed under oath and provide information that could clean up the sport was born out of fear that he could risk "potential criminal and civil liability".
Armstrong, accused by Usada last October as leading the "most sophisticated, professionalised and successful doping programme that sport has ever seen", had been given the chance to reveal details about the use of performance-enhancing drugs in cycling. However, a deadline to state his willingness formally to cooperate was put back by two weeks on 6 February and was on Wednesday rejected.
The disgraced rider had been in talks with Usada but his attorney, Tim Herman, said in a statement that Arnstrong would not comply with a process that would "only demonise selected individuals".
Armstrong's decision not to co-operate means his lifetime ban from sport will be upheld, and Usada believes that the reason behind the announcement was down to a fear that he could face lawsuits in the future.
A Usada statement said: "We have provided Mr Armstrong several opportunities to assist in our ongoing efforts to clean up the sport of cycling. Following his recent television interview we again invited him to come in and provide honest information and he was informed in writing by the World Anti-Doping Agency that this was the appropriate avenue for him if he wanted to be part of the solution.
"Over the last few weeks he has led us to believe that he wanted to come in and assist Usada but was worried of potential criminal and civil liability if he did so. Today we learned from the media that Mr Armstrong is choosing not to come in and be truthful and that he will not take the opportunity to work toward righting his wrongs in sport. At this time we are moving forward with our investigation without him."
Armstrong, who has been stripped of his seven Tour de France titles, admitted to doping during a TV interview with Oprah Winfrey in January. However, Usada believes that his confession did not go far enough and that a number of details remained unresolved.
A statement from Armstrong's attorney read: "Lance is willing to cooperate fully and has been very clear: he will be the first man through the door, and once inside will answer every question, at an international tribunal formed to comprehensively address pro cycling, an almost exclusively European sport.
"We remain hopeful that an international effort will be mounted and we will do everything we can to facilitate that result.
"In the meantime, for several reasons, Lance will not participate in Usada's efforts to selectively conduct American prosecutions that only demonise selected individuals while failing to address the 95% of the sport over which Usada has no jurisdiction."
Earlier in the month ABC News reported that Armstrong was under criminal investigation by US federal agents, saying the agents were "actively investigating Armstrong for obstruction, witness tampering and intimidation".
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