Lance Armstrong could end up in court facing allegations of perjury and an attempt to reclaim millions of dollars of bonus money if a Texas-based insurance company decides to try to win back a payment to the disgraced cyclist that was made for winning the 2004 Tour de France.

SCA Promotions had promised to pay Armstrong $5m in bonus money if he managed five consecutive Tour de France wins, but refused to do so amid widespread media rumours of doping. Armstrong took the company to arbitration, where he received a settlement of $7.5m, made up of the original bonus plus interest and lawyers' fees.

In the wake of a damning report accusing Armstrong of being at the centre of "sport's most sophisticated, professionalised and successful" doping programme, there is every prospect that the issue will be legally revisited, perhaps including charges of perjury if Armstrong can be shown to have lied during testimony first time around.

Jeff Dorough, a lawyer for SCA, told the Guardian that the firm would await a reaction to the report – which was published by the US Anti-Doping Agency (Usada) – from the world cycling governing body, the International Cycling Union (UCI). The UCI has not yet officially responded to the Usada investigation.

"We will readdress the issue when we see if there is inaction or action from UCI," Dorough said.

However, it is believed that it is likely that SCA will eventually take legal action, given the exhaustive nature of the Usada report. In more than 1,000 pages Usada detailed the alleged doping using testimony from 26 people, including 15 riders with knowledge of Armstrong's US Postal Service and Discovery Channel teams between 1998 and 2005. The study accused Armstrong, who has always protested his innocence, of effectively running a systemic blood-doping ring.

The SCA case is not the only potential legal threat to Armstrong. An investigation into allegations that Armstrong used performance-enhancing drugs was dropped earlier this year by Andre Birotte, the US attorney for the central district of California. Birotte's office offered little explanation for the move, which came as a surprise to many in the global cycling community.

A spokesman for Birotte's office, Bruce Riordan, said: "Our office declines to comment on the matter in question."

Some experts, however, believe that the investigation may be reopened as widespread outrage over the allegations in the Usada report creates political pressure to explain why it was dropped in the first place.

"The US attorney's office is always subject to political pressures. The criticism now will hit home and there is a good chance that the government will indict and charge Armstrong," said Peter Keane, a law professor at the Golden Gate University.

Mike Straubel, from Valparaiso University, agreed. "It is more of a political question than a legal one, but I would say there is a 70% chance of the case being reopened," he said.

But others suspect there is little appetite for a re-opening a prosecution against Armstrong. They argue that the likelihood is that government lawyers had already amassed the same evidence as Usada, but had been put off by the high burdens of proof associated with putting a criminal case in front of a jury.

The Guardian also understands that this aspect is a serious concern to government lawyers as they digest the reaction to the Usada report.

"I think everything in the Usada report, the government already saw. I don't think it is new information to them. Are they going to prosecute Lance Armstrong? I think the answer is no," said top California criminal attorney Paula Canny.

Canny said Birotte and his team were likely mindful of the political implications of taking on the Armstrong case again, as the alleged crimes took place several years ago and involve a man who is still deeply involved in the fight against cancer. They would also likely base a case on issues like fraud, rather than steroid abuse in a sporting competition.

"They have a different and very high standard of proof that they would have to get," she said.

Any decision by Birotte to re-open the Armstrong investigation would come after two other high-profile sports cases that ran into trouble. In December 2011, prosecutors were able to convict the baseball star Barry Bonds of obstructing justice, but not of steroid abuse. In June this year, another baseball icon, Roger Clemens, was acquitted of all charges in a perjury trial over steroids.

"If I were a betting man I would say they are absolutely, positively not going to re-open the investigation," said Professor Jordan Kobritz, chair of the Sports Management Department at SUNY Cortland.

Kobritz said that any criminal prosecution would be tough to prove to a jury and would cost millions of dollars.

"It is a giant leap. But even if you took [that leap], there are better ways of spending taxpayers' money than prosecuting Lance Armstrong," he said.

For the moment Armstrong is holding firm to his line that he has been the victim of a witch hunt. His lawyer, Tim Herman, has called the Usada report a "hatchet job" put together by people with grudges to settle or personal interests to look out for. That argument seems to have won through – for the moment at least – with sponsors and the cyclist's charity, the Lance Armstrong Foundation, which is renowned for the Livestrong yellow bracelets that have become a world symbol of the fight against cancer.

The LAF president, Doug Ulman, backed Armstrong and slammed Usada. "Usada appears motivated more by publicity rather than fulfilling its mission. Lance Armstrong's legacy as a cancer fighter is literally second to none," he said in a statement.

Armstrong's cancer work may also provide a cover for his many sponsors to stand by him, betting that the general public will still see his work in fighting the illness that nearly killed him as being far more important than his sporting behaviour. The sports giant Nike has issued a supportive statement and a host of other sponsors – representing everything from bikes to energy products – have simply declined to comment.

For Kobritz, that silence speaks volumes. Even the Post Office – which sponsored his racing team – has declined to address the allegations.

"A lot of people who think he's guilty are going to say: 'So what? Maybe he did dope but look at what else he's done,'" Kobritz said. However, he added: "If anyone still believes he was not doping, then they believe in Santa Claus."