CBS had this tape, which completely refuted Obama's claim in the second debate, and they chose it sit on it until the Sunday night before the election. Even then, they did not announce they were dropping this previously withheld tape, it was discovered and then publicized by others.
As the source says, an astonishing display of media malpractice, and one that almost certainly would not have occurred if the president was a Republican.
Video embedded below.
"In an astonishing display of media malpractice, CBS News quietly released proof--two days before the election, far too late to reach the media and the public--that President Barack Obama lied to the public about the Benghazi attack, as well as about his later claim to have called the attack "terrorism" from the beginning.
CBS unveiled additional footage from its 60 Minutes interview with President Obama, conducted on Sep. 12 immediately after Obama had made his statement about the attacks in the Rose Garden, in which Obama quite clearly refuses to call the Benghazi an act of terror when asked a direct question by reporter Steve Kroft"