You may remember PBS luminary Bill Moyers who had been Lyndon Johnson’s press secretary.
Bob Novak (of Evans & Novak and The Capital Gang) said that Bill Moyers had copies of the MLK tapes and he was going around playing them for the entertainment of the elite DC press corps.
Bill Moyers of course was A Good Liberal like the rest of the LBJ crew so that trick can’t be blamed on the very few conservatives roaming DC in those days, Novak being one of them. Anyway all of the big name press of that time knew what was in the tapes of MLK, they had all heard them. Only the public at large didn’t know about them.
Bill Moyers was more than a press secretary. He was Johnson’s chief of staff and confidante. An amazing man. You might not like his politics but he was impressive.