Wild. The previous post about erased and archived and someday-to-be-resuscitated Nixon reminded longtime greg.org reader Jonathan of another obscured national conspiracy: the Dictabelt recordings of the Kennedy assassination.
Apparently, a motorcycle policeman along the presidential motorcade route through Dallas had his mic stuck open, and he inadvertently laid down several minutes of audio on a police radio channel, which was being recorded by something called a Dictabelt.
Generations of investigators who examined the recording drew controversial and sometimes conflicting conclusions from it about the participation of a second gunman. But basic questions about which policeman's radio was being recorded, and where he was at the time, have never been answered definitively.
In any case, the celluloid acetate medium on which the recording was made is microscopically degraded further with every pass of the stylus. So the more it is disputed and heard and analyzed, the more it is physically erased.
Dictabelt evidence relating to the assassination of John F. Kennedy [wikipedia, thanks jf]
