In a statement released Wednesday, the network described the story as "truthful, accurate and fair."
"Lance Armstrong and his lawyers were given numerous opportunities to respond to every detail of our reporting for weeks prior to the broadcast and their written responses were fairly and accurately included in the story," the network said. "Mr. Armstrong still has not addressed charges by teammates Tyler Hamilton and George Hincapie that he used performance-enhancing drugs with them."
Jeff Fager, the chairman of CBS News, said the network found at least three mistakes in a letter from Keker & Van Nest, the high-powered San Francisco firm representing Armstrong.
Armstrong won the Tour de France a record seven consecutive times. It was especially remarkable because his career was interrupted by treatment for testicular cancer before his first Tour victory.