<photo: Walker's 1975 letter to Senator Frank Church saying he heard Oswald's name "within days" of the Walker shooting on April 10, 1963; flatly refuting his own Warren Commission testimony. > The 1996 book, Assignment Oswald, by former Dallas FBI agent James Hosty, offered a JFK conspiracy theory which was first shredded by J. Edgar Hoover in 1964, and then shredded by Bill Simpich in 2014. In my reading, Hosty’s CT actually shows how close he was to the Dallas plotters.