The Terrorism Expert is a man seen in the Weazel News special report trailer for The Ballad of Gay Tony. Weazel News interviewed him on what weapons possible "terrorists" use in Liberty City. It is assumed that he drives a Admiral, as it is seen in the Weazel News Trailer.
The model of the character is in fact available in the base game, Grand Theft Auto IV, titled "
gunnut"; it is possible via mods to switch the player's model to that of this character.