David E. Scheim is a director of management information systems. He is the author of several books on the murders of John F. Kennedy and Robert Kennedy. David is the author of "Contract on America: The Mafia Murder of President John F. Kennedy" which is a reexamination of the Mafia's role in the assassination of John F. Kennedy discusses Jack Ruby's criminal activities, his top-level Mafia ties, and how the Warren Commission blatantly covered up the evidence.