Volume III of the HSCA hearings volumes consists of the proceedings of Sept. 18 through 21, 1978. This included testimony from Cuban officials, the Secret Service, and former members of the Warren Commission.

Following narrative by the HSCA's Chief Counsel G. Robert Blakey, the first witness on Monday, Sept. 18 was Eusebio Azcue Lopez, former Cuban Consul in Mexico City. Azcue reiterated his belief that the person he dealt with in the fall of 1963 was not Lee Harvey Oswald. Azcue was followed by Alfredo Mirabal Diaz, who replaced Azcue as Consul and was also present during the "Oswald" visit.

The Sept. 19 proceedings began with Thomas Kelley, an inspector for the Secret Service, who conducted the Secret Service' investigation into the assassination. Mr. Kelley was followed by Secret Service Chief James Rowley. The following day, testimony was heard from two FBI agents involved in its investigation, James Malley and James Gayle.

Sept. 22's proceedings included the testimony of three Warren Commissioners and its General Counsel: Former President Gerald Ford, John Sherman Cooper, John J. McCloy, and J. Lee Rankin. They were followed by Nicholas Katzenbach, who was Assistant Attorney General at the time of the assassination and had written the famous "Katzenbach memo."