The last of the five Hearings volumes of the HSCA consists of the proceedings of Sept. 27 and 28, 1978, plus an additional day of hearings held on December 29, 1978. The September testimony was concerned primarily with organized crime. The final day of hearings, held 3 months later, dealt with acoustics evidence.

Sept. 27 was taken up largely by the testimony of Ruby associate Lewis McWillie, who worked in gambling casinos in Havana and Las Vegas. McWillie was followed by Jose Aleman, a Cuban exile who was the son of a former Cuban minister of education.

The following day, Sept. 28, began with the testimony of organized crime boss Santos Trafficante, followed by a presentation by Ralph Salerno, the Committee's consultant on organized crime. After Salerno the Committee questioned Judge Burt Griffin, a former Warren Commission staffer who had been involved in the Ruby investigation.

Three months later, on Dec. 29, the Committee heard more testimony on the acoustics evidence which indicated a fourth grassy knoll shot. Witnesses included Professor Mark Weiss and Ernest Aschkenasy, Dallas Police Officer H. B. McLain, and Dr. James Barger. Closing remarks were made by Chief Counsel G. Robert Blakey and Chairman Louis Stokes.