Here is Hinckle's account of a November 5, 1968, conversation:
The caller was in no mood to inquire about the weather. "This is urgent," Jim Garrison said. "Can you take this in your mailroom? They'd never think to tap the mailroom extension."
. . . Garrison began talking when I picked up the mailroom extension: "This is risky, but I have little choice. It is imperative that I get this information to you now. Important new evidence has surfaced. Those Texas oilmen do not appear to be involved in President Kennedy's murder in the way we first thought. It was the Military-Industrial Complex that put up the money for the assassination -- but as far as we can tell, the conspiracy was limited to the aerospace wing. I've got the names of three companies and their employees who were involved in setting up the President's murder. Do you have a pencil?"
I wrote down the names of the three defense contractors -- Garrison identified them as Lockheed, Boeing, and General Dynamics -- and the names of those executives in their employ whom the District Attorney said had been instrumental in the murder of Jack Kennedy. I also logged a good deal of information about a mysterious minister who was supposed to have crossed the border into Mexico with Lee Harvey Oswald shortly before the assassination; the man wasn't a minister at all, Garrison said, but an executive with a major defense supplier, in clerical disguise. I knew little about ministers crossing the Rio Grande with Oswald -- but after several years of fielding the dizzying details of the Kennedy assassination, I had learned to leave closed Pandora's boxes lie; I didn't ask.
I said that I had everything down, and Garrison said a hurried goodbye: "It's poor security procedure to use the phone, but the situation warrants the risk. Get this information to Bill Turner. He'll know what to do about the minister. I wanted you to have this, in case something happens . . . ." (Hinckle, If You Have a Lemon, Make Lemonade, 198-9)