Series of events critical to legacy

Four months after federal officials dropped a nearly 2-year-old investigation of seven-time Tour de France winner Lance Armstrong, the U.S. Anti-Doping Agency is aggressively pursuing a case against him. Armstrong, his longtime team director Johan Bruyneel of Belgium, his personal trainer Dr. Michele Ferrari of Italy, two former U.S. Postal Service team doctors and a team trainer from Spain received a letter dated June 12 notifying them of USADA's intention to file charges against them for a laundry list of offenses. If convicted, Armstrong could be stripped of his Tour victories and barred for life from any role in professional cycling or competing in Ironman triathlons.

Q: Why would USADA file charges against Armstrong when the government didn't?

A: The case that federal investigators were building against Armstrong and other defendants was centered on financial fraud, not performance-enhancing drug use. No U.S. athlete has ever been prosecuted for doping, only trafficking or other crimes related to doping. The case would have pivoted on the government's ability to prove that U.S. Postal Service sponsorship funds were diverted to subsidize organized doping on the cycling team led by Armstrong, thus breaching a contractual clause.

After extensive evidence gathering and testimony before a grand jury in the Central District of California, U.S. Attorney Andre Birotte Jr. announced in February that he was terminating the investigation. He offered no explanation for his decision, but speculation has run the gamut, from a weak legal rationale to the difficulty of convicting a global celebrity to political pressures.

USADA is not a law enforcement agency, and its standard of proof is entirely different. Although a criminal conviction would require proof beyond a reasonable doubt, USADA needs to show "clear and concise" evidence. According to the letter, Armstrong could face sanctioning for a variety of doping violations including use of, possession of, trafficking in and administering performance-enhancing drugs to other riders and conspiring to cover up that web of blood doping and use of illicit substances and masking agents. It is the trafficking charge that could lead to a lifetime ban from Olympic sports. USADA is the charging body, but it does not ban athletes; the sports federations do.

Q: How can Armstrong be charged in the absence of a positive doping test?

A: The World Anti-Doping Agency code enables anti-doping authorities to charge athletes based on "nonanalytical positives,'' or evidence of doping violations that does not derive from a positive test. That evidence could include eyewitness testimony, documents, correspondence, financial records or possession of banned substances.

In Armstrong's case, USADA cites witnesses who say they saw Armstrong use EPO, testosterone, corticosteroids, blood transfusions and masking agents to enhance his athletic performance. The letter also references results of blood tests done in 2009 and 2010 by the UCI, cycling's international governing body. Although none of the individual samples produced a positive test, taken together, the profile they present is "fully consistent with blood manipulation including EPO use and/or blood transfusions,'' the letter states. Introducing those results as evidence would require interpretation by a scientific expert, and any Armstrong defense presumably would include an expert to try to refute those findings.

Q: Why would USADA have jurisdiction over the other people targeted in the letter, none of whom are U.S. citizens?

A: Under UCI rules, the national anti-doping agency that unearths evidence of a nonanalytical violation has jurisdiction over the case, regardless of where the violation occurred or the citizenship of the accused. Bruyneel -- currently the manager of the RadioShack-Nissan cycling team -- and the doctors and trainer could all be barred from any roles in professional cycling if USADA prevails.

Q: What happens next procedurally?

A: Armstrong has until June 22 to respond to the letter. At that time, any written submissions he and his lawyers made would be presented, along with a summary of USADA's evidence, to the agency's independent review board. The review board does not rule on any specific evidence or legal arguments but decides whether the totality of evidence is enough to proceed. If so, Armstrong could opt to accept sanctions or ask for an arbitration hearing, which would be closed to the public unless he requested otherwise. Both sides may call witnesses (USADA can issue subpoenas and go to court to enforce them) and introduce evidence. The letter states that a hearing could reasonably be scheduled before November.

In an interview with Men's Journal magazine earlier this spring, Armstrong implied he would not fight if USADA brought charges. If he chose not to contest USADA's evidence, the agency could unilaterally impose sanctions.

Q: What potential sanctions does Armstrong face?

A: Armstrong has been competing in triathlons in a bid to qualify for the Ironman world championships this fall. USADA's letter was copied to the World Triathlon Corp., which runs Ironman events in the United States and overseas and is a signatory of the WADA code. The WTC immediately suspended Armstrong from competition under a provision of its own rules. If convicted of multiple doping offenses, Armstrong could receive up to a lifetime ban from any sports whose federations abide by the WADA code. He would forfeit all results and prize money from the period of time referenced in the charges.

The statute of limitations for doping violations under the WADA code is normally eight years, but USADA contends in the letter that the ongoing conspiracy to cover up years of organized doping on different teams should enable the agency to convict for older offenses, i.e., those that occurred before 2004. There is a recent precedent for this line of argument.

If Armstrong is convicted, the UCI has the authority to strip him of Tour titles, as the federation has done in the Floyd Landis and Alberto Contador cases.

Q: Who might testify against Armstrong and under what conditions?

A: The charging letter stated that "more than 10" cyclists and team employees from five different organizations witnessed the violations alleged by USADA. (According to the letter, every rider contacted by USADA except Armstrong cooperated with the agency.) Two former Armstrong teammates -- Landis and Tyler Hamilton, who both fought and lost doping cases, served suspensions and are now retired -- later confessed and went public with allegations against Armstrong.

Landis cooperated with federal investigators, and Hamilton testified before the grand jury. Both have been asked to testify in any potential USADA proceeding against Armstrong. Numerous other riders spoke with USADA investigators in sessions that were separate from their interviews by federal authorities or their grand jury testimony. Under the WADA code, athletes who provide "substantial assistance" in resolving doping cases can have their own sanctions reduced or eliminated.

Language in the letter indicates that USADA has relevant evidence that reaches well back into the 1990s and specifically references 1996. That was the year Armstrong was diagnosed with testicular cancer and the same year that his then-teammate Frankie Andreu and Andreu's wife, Betsy, heard him admit to doping, as they have previously testified.

Q: Why bring the case now?

A: USADA waited until the federal criminal investigation in Los Angeles had run its course, then asked authorities to share evidence. Neither USADA nor the government will confirm any details of their communication, but a lawyer familiar with the case told ESPN.com that the USADA case is based on the agency's evidence alone.

As noted above, USADA is arguing that WADA's eight-year statute of limitations on doping violations should be waived in any potential case against Armstrong because of a conspiracy to cover up older offenses. If USADA were to be limited to pursuing violations within that eight-year period, Armstrong still could lose his 2004 and 2005 Tour de France titles and prize money. (The 2012 Tour begins June 30 in Liege, Belgium.)

One other consideration is that USA Cycling is about to name its roster for the upcoming Olympic Games. Although USADA cannot prevent a rider from being selected, now that USA Cycling has been notified of USADA's intent to file charges, it will be up to the cycling federation to try to avoid the potentially messy situation of sending an athlete to London whose name might later surface in a doping case.

Q: Could Armstrong face additional legal action?

A: Investigators from several federal agencies are continuing to gather evidence to decide whether the civil division of the Department of Justice will intervene in a whistleblower case, also known as a qui tam case, filed against Armstrong and other former U.S. Postal Service cycling team associates in late 2010.

The case remains under seal, but sources told ESPN.com at the time the suit was filed that Landis, Armstrong's former teammate, was the plaintiff. Qui tam suits allege that government funds have been misused, fraudulently obtained or stolen. They have a much higher success rate when the DOJ intervenes on behalf of the plaintiff. The U.S. Postal Service sponsored the team from 1998 to 2004, and the total amount of the contracts during its sponsorship of the team from 2001 through 2004 alone was $32 million. If the government prevails in a qui tam suit, defendants can be liable for treble damages, a portion of which goes to the original plaintiff.

SCA Promotions, the Dallas-based insurance company that tried to keep Armstrong from collecting a $5 million bonus for his multiple Tour wins because of doping allegations, could explore legal options to recoup its money. The case went to arbitration in 2006 and, after extensive testimony, was settled in Armstrong's favor based on contractual language. The company paid Armstrong his full bonus plus legal costs. SCA representatives have been closely monitoring developments in Armstrong's case since the federal investigation focused on him starting in May 2010.

T.J. Quinn of ESPN's Enterprise/Investigative Unit contributed to this report.