In a searing letter sent to the U.S. Anti-Doping Agency Review Board on Friday, Lance Armstrong made it clear he intends to fight the agency’s allegation that he participated in a vast doping conspiracy while winning his seven Tour de France titles.

In the 11-page letter signed by Armstrong’s Washington-based attorney, Robert D. Luskin, Armstrong asked the agency’s independent review board to reject the charges made by USADA or suspend consideration of the matter until the agency provides evidence to back up allegations made in a June 12 letter to Armstrong.

Armstrong’s response claims USADA made unsupported or flatly false allegations in its letter that are “offensive to any notions of due process and fair play.”

The Armstrong letter indicates that, for the moment, he does not intend to take the matter to state or federal court but hopes to stave off the claims against him within USADA’s own system.

“USADA’s overly expansive view of its own authority — not to mention smug self-regard — undoubtedly explains its threadbare charging document, its arrogant and craven refusal to disclose its evidence, and its complacent expectation that the Review Board will not hold it accountable,” the letter stated.

The review board evaluates the agency’s evidence before USADA issues any punishment or the matter goes to arbitration. USADA can reject the recommendation of its review board if it chooses. The vast majority of doping cases brought before the board involve positive tests, for which there are defined and clear standards for evidence.

If the review board supports USADA’s charges, the agency would then issue a formal ban; USADA said in its charging letter that the charges could bring a lifetime ban. Armstrong could then request an arbitration hearing through the American Arbitration Association.

Because USADA charged Armstrong with doping violations between 1998 and 2005, all of Armstrong’s seven Tour titles are in jeopardy should he be found guilty. The charges from USADA come just four months after the U.S. attorney’s office in Los Angeles closed its criminal investigation into doping allegations surrounding Armstrong after a nearly two-year inquiry.

“When we have evidence that a person has doped, we follow established procedures that were approved by athletes, the U.S. Olympic Committee, and all Olympic sports organizations,” USADA said in a statement. “Every person accused has the right to a full public hearing where all of the evidence will be presented to an independent group of arbitrators who ultimately decide the case. The established rules provide full due process and are designed to get to the truth.”

Armstrong has never tested positive, so the charges do not include a clear-cut positive test. However, the agency alleged that Armstrong produced blood results in 2001 and in 2009 and 2010 that indicated the use of the endurance-boosting drug EPO.

In the letter, Luskin argued the charges have no merit and both suggest “clear violation of the USADA Protocol and should not be tolerated.”

The letter noted that USADA said Swiss lab director Martial Saugy stated that a 2001 urine sample from Armstrong was consistent with the use of EPO, yet Saugy told The Washington Post in an interview last year that the sample could not be called positive and that he would not say so in any court.

The letter also demands information on the 10 witnesses who USADA says provided first-hand accounts of the allegations raised in the charging letter, which accuse Armstrong and five of his non-rider associates from four different cycling teams of participating in a long-running doping conspiracy.

That USADA refused to provide any information about the witnesses, the letter said, “is a disgrace, and highly probative of USADA’s readiness to employ unlawful tactics and questionable practices in its zeal to punish Mr. Armstrong at all costs.”

The letter further claimed that USADA overreached in suggesting that the eight-year statute of limitations on doping allegations does not apply because of the alleged conspiracy and attempts to cover up the doping.