So defrocked 2006 Tour de France champion Floyd Landis is the latest in a long line of accusers to pile doping allegations on Lance Armstrong, and Armstrong -- for the umpteenth time -- has insisted he's not a cheat? Armstrong damn well better not be. If the world's most famous cancer survivor has been lying to us all these years, then Armstrong didn't just collect seven ill-gotten Tour de France titles. He'd be guilty of a deceit of unconscionable callousness because of the special constituency he eagerly represents.

Armstrong would be guilty of conning everyone who has used his stirring example or best-selling autobiography as a blueprint for confronting cancer in their lives.

He'd level a blow of unfathomable cruelty to the millions of survivors of the disease in the United States alone whom Armstrong often invokes -- sometimes with tears welling up in his eyes -- as the "silent army" that helped him soldier on from one cycling victory to the next.

Armstrong is a seven-time winner of the most prestigious bicycle race in the world. Did he win honestly? Joel Saget/AFP/Getty Images

To this day, thousands of Armstrong's fans make pilgrimages to his races just to catch a glimpse of him as he blurs by. His Livestrong foundation says it has sold more than 70 million yellow bracelets in his crusade to help fund cancer research. He once filmed a heart-tugging commercial that showed him flying through city streets on his bike, acknowledging cancer victims who had run to the windows of their hospital ward to wave excitedly at him. He has constantly presented himself as flesh-and-blood proof that no matter how dire or impossible things may seem, there's hope.

That's why the specter of Armstrong being a drug cheat feels worse -- and somehow different -- than all the other fallen heroes in a sports landscape awash with dopers.

Landis' history of lying, even after he failed the drug test that cost him his Tour de France title, makes him a flawed messenger, all right. But if his laundry list of accusations against Armstrong, Armstrong's longtime team director Johan Bruyneel and some other cyclists on their now-disbanded U.S. Postal Service squads are true, Armstrong would be instantly transformed from one of the most inspirational stories in sports history to a pariah.

He'd deserve to leapfrog to the front of the modern rogue's gallery in sports, bumping anyone else you could name -- Michael Vick, Ben Roethlisberger, Tiger Woods, baseball's steroid cheats -- to the side wings.

"We have nothing to hide; we have nothing to run from," Armstrong calmly parried back last week in a surgical dissection of Landis that touched on everything from Landis' "credibility" issues to the inaccuracies in his timeline of events to Landis' possible motives.

Some credit him with almost single-handedly saving the Tour de France over the last decade. AP Photo/Peter Dejong

Speaking to reporters outside a team van at the Amgen Tour of California race, Armstrong maintained that he and numerous other cycling insiders had been the subject of "harassment" and "threats" from Landis for more than a year before Landis finally made his charges public in an ESPN.com story.

"If someone said give me one word to sum this all up, I'd say 'credibility,'" Armstrong said. "Floyd lost his credibility a long time ago If you saw the rest of the e-mails we have, it speaks volumes to his mental state It's our word against his word. I like our word."

Teasing out the truth about Armstrong has always been a complicated matter. Despite the huge following and sainted public image he's long enjoyed, the backstage truth about Armstrong is he's an exacting, obsessively driven, often brusque man. He's picked his share of fights and unceremoniously fired members of his support team at times, only to see some of them turn up in tell-all books or stories suggesting his results are tainted.

Armstrong likes to point out he's never failed a drug test. But the idea that Armstrong could become a far better rider after nearly dying of brain and testicular cancer while saddled with the added handicap of competing in a sport rife with confessed dopers remains incomprehensible to some people. For years, he's complained he's the victim of witch hunts. He worries about would-be saboteurs.

So far, nothing has stuck. But among all his enemies, Landis could present a more serious problem.

Landis was a support rider for Armstrong with the U.S. Postal Service team during some of Armstrong's Tour de France-winning years. A federal investigator named Jeff Novitzky is now interested in the stories Landis is telling about being given vials of EPO and human growth hormone when he raced on Armstrong's team; getting testosterone shots from Armstrong's controversial former adviser, Italian doctor Michele Ferrari; and being asked by Armstrong to stay at his training-base house in Girona, Spain, to babysit oxygen-rich bags of blood that would be used later for the sort of endurance-boosting transfusions Landis says he also witnessed.

Jeff Novitzky has been a thorn in Barry Bonds' side for years. Now he's reportedly investigating Armstrong. Scott J. Ferrell/Congressional Quarterly/Getty Images

All those tales are variations of sins Armstrong has been accused of before.

If Novitzky's name sounds familiar, it should. He's the man who spearheaded the BALCO investigation that eventually ensnared Barry Bonds, Roger Clemens and Marion Jones, among others. Unlike the other people who have snooped for skeletons in Armstrong's closet, Novitzky has the hammer of government subpoenas. And Landis is cooperating with him. Others must be, too.

"Everything will come out in the end," Armstrong shrugged last week when a possible federal inquiry was mentioned.

Would he tell the truth to the Feds?

"Absolutely," Armstrong said.

Hopefully, he's been telling the truth all along.

After he won his last Tour de France title in 2005, Armstrong couldn't resist chiding his detractors from the victory podium by saying, "I feel sorry for you. I'm sorry you don't believe in miracles."

Until conclusive proof of his guilt surfaces, Armstrong's denials deserve to be respected. Not because he says he's innocent -- they all say that -- but because lying about his case, given the special constituency he has, would be reprehensible.

Johnette Howard is a contributing columnist to ESPN.com and ESPNNewYork.com, and is the author of "The Rivals: Chris Evert vs. Martina Navratilova, Their Epic Duels and Extraordinary Friendship." She can be reached at jphinbox@yahoo.com.

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