United States Anti-Doping Agency head Travis Tygart has claimed Lance Armstrong is still lying about the full extent of his doping past.
Tygart, the USADA chief executive who was one of the key figures in exposing the disgraced cyclist, insisted there was scientific proof that Armstrong did use performance-enhancing drugs on his comeback to the sport, in 2009 and 2010.
The cyclist finally admitted in his interview Oprah Winfrey that he did dope in all seven of his Tour de France wins, but maintained he raced clean when he came out of retirement.
But Tygart told CBS' 60 Minutes programme: "(That is) just contrary to the evidence. The evidence is clear.
"His blood tests in 2009, 2010, expert reports based on the variation of his blood values from those tests, one to a million chance that it was due to something other than doping."
Tygart claimed there were clear reasons for Armstrong to proclaim his innocence during those later years as it meant he would be exempt from possible criminal prosecution, because there is a five-year statute on a charge of fraud.
The USADA revealed last year that Armstrong had led "the most sophisticated, professionalised and successful doping programme sport has ever seen", with the International Cycling Union (UCI) subsequently stripping him of his seven Yellow Jerseys.
Eleven of Armstrong's former team-mates testified to USADA about his doping regime, in which they had been involved. Some were given bans of six months, but Tygart said there was only one course of action for Armstrong if he wanted is lifetime ban from USADA lifted.
"He would have to come in just like all 11 of his team-mates did and testify truthfully about all of those who were involved with him pulling off this grand heist," Tygart said.
USADA have given Armstrong a deadline of February 6 to agree to confess all under oath.
Tygart revealed, in pursuing Armstrong, he had received death threats in the form of anonymous emails and letters.
"The worst was probably (a threat to put) a bullet in my head," he said.
"I turned it over to the FBI to investigate it, which they're doing."
Tygart also claimed that had Armstrong prevailed and USADA failed in the case, it would have sent out a message that it is possible to "cheat your way to the top".
"And if you get too big and too popular and too powerful, if you do it that well, you'll never be held accountable" he added.
Tygart reiterated his accusation that Armstrong had influence over the UCI, something both parties have denied.
Tygart said: "I think their (the UCI's) involvement was a lot deeper in him pulling off this heist than he was willing to admit to."
And he also again accused Armstrong of trying to pay off USADA.
"I received a phone call from one of his closest associates and they offered us the money," he said.
Armstrong has denied trying to pay them off.
Tygart labelled Armstrong's claims his use of performance-enhancing drugs during his career made it a level playing field "amazing" and "simply not true".
The Texan told Winfrey: "That's like saying we have to have air in our tyres or water in our bottles. It was part of the job.
"I looked up the definition of cheating and the definition is 'to gain an advantage on a rival or foe'. I did not view it that way. I viewed it as a level playing field."
Tygart said: "It's amazing. You could go to almost any kindergarten in this country or frankly around the world and find kids playing tag or four square and ask them what cheating is. Every one of them will tell you (cheating) is breaking the rules of the game.
"No real athlete has to look up the definition of cheating. It's offensive to clean athletes who are out there working hard to play by the rules that apply to their sport."