The Killian documents controversy involved six documents containing false allegations about President George W. Bush's service in the Texas Air National Guard in 1972–73, allegedly typed in 1973. Dan Rather presented four of these documents as authentic in a 60 Minutes II broadcast aired by CBS on September 8, 2004, less than two months before the 2004 presidential election, but it was later found that CBS had failed to authenticate them. Several typewriter and typography experts soon concluded that they were forgeries. Lieutenant Colonel Bill Burkett provided the documents to CBS, but he claims to have burned the originals after faxing them copies.