Cycling: Legacy in tatters. $7m in question. Now Lance Armstrong may end up in jail

Criminal trial for perjury may be next for fallen idol after denial of doping – on oath

"So ends one of the most sordid chapters in sporting history," are the last words of the United States Anti-Doping Agency's unprecedentedly damning investigation into cyclist Lance Armstrong, one of the most celebrated and now one of the most shamed sportsmen in history. But the publication of the Usada's decision marks only the beginning of a mountain of difficulties facing the 41-year-old Texan, who is still, technically, a seven-time Tour de France winner.

Even though Armstrong decided in August to stop fighting doping allegations – he continues to deny them – he will not be able to ignore the report's many consequences. He may face perjury charges, have to hand back millions of dollars in prize money (as well as an Olympic medal) and could lose millions in donations to his Lance Armstrong Foundation for cancer survivors.

Armstrong denied doping under oath to a Dallas court in 2005, testimony that Usada has called "materially false and misleading". Although Armstrong maintains his innocence, if US prosecutors disagree there are grounds for perjury charges.

The cyclist went to a court for civil arbitration in November 2005, when SCA Promotions Inc and Ted Lyonhamman Insurance Services did not want to pay him a $5m bonus for winning his sixth consecutive Tour de France amid growing doping rumours. Among seven potentially perjurious statements, Armstrong claimed to have never taken any performance enhancing drug in connection with his cycling career, despite evidence now regarded as "irrefutable" by everyone from Bradley Wiggins to Sir Chris Hoy.

Cycling's governing body, the Union Cycliste Internationale (UCI) has 21 days to respond to Usada. The intricacies of the relationships between governing bodies and the anti-doping organisations means that Armstrong has not formally been stripped of his seven Tour de France titles. If the UCI do so, which it almost certainly will, he will be required to return about $7m in prize money. Whether he will have to also return the bronze medal he won in the Olympic Time Trial in Sydney in 2000 – the same event won by Bradley Wiggins this year – is unclear. The International Olympic Committee (IOC) has a statute of limitation of eight years in which it will change results and strip athletes of their medals. But the Usada report links Armstrong to doping offences committed in 1998, which might allow the IOC to act under a different legal basis.

Armstrong has been blasé in the face of the extraordinary report, Tweeting yesterday that he was "Hanging @LIVESTRONGHQ [the headquarters of his charity in Austin, Texas] with the team talking about next week's events and plans for 2013. Can't wait to see so many friends and supporters". Earlier he had tweeted a link to the Elliott Smith song "Coming Up Roses".

Previous public falls from grace, such as that of Tiger Woods, have seen sponsors walk away, but Armstrong's case is intriguing as his deals are all tied with his charitable foundation for cancer survivors, and his main sponsors – Nike, Oakley and beer makers AB Inbev – have understandably so far not distanced themselves from him.

Next weekend, a series of events are scheduled to take place in Austin to mark Livestrong's 15th anniversary, and none of the Hollywood A-listers who had confirmed their attendance before the report's publication have given any indication they will not be there.

Mayor of Austin, Lee Leffingwell, told reporters: "I am proud of my friendship with Lance Armstrong. His incredible generosity of spirit has been and remains an inspiration to me and countless others, and can never be taken away."

Sunglass manufacturer Oakley's last word on the matter, in August, was to say that it "supports its athletes who respect and honour the ethics of sports until proven otherwise". Nike has donated more than $100m to the charity and has so far said it will stand by Armstrong.

They did the same with Woods and basketball star Kobe Bryant, when he was accused of sexual assault, but in both cases quietly and substantially reduced their involvement with the stars.