Jack Dunlap

Jack E. Dunlap (November 14, 1927-July 23, 1963) was a United States Army sergeant stationed at the National Security Agency who later became a spy for the Soviet Union in the early 1960s.

NSA spying activities
In order to continue his access to classified information, Sgt. Dunlap applied for civilian employment at the NSA. At the time, background investigations were more strict for civilian employees than members of the military. When the NSA began Sgt. Dunlap's background investigation, indications of Dunlap's "high lifestyle" began to emerge. Dunlap's security clearance was revoked on May 23, 1963, and the NSA transferred Dunlap to a menial job.

Death and related controversies
Dunlap committed suicide by carbon monoxide poisoning on July 23, 1963; James Jesus Angleton, the director of counter-intelligence at the CIA at the time, has long been rumoured to have been involved in Dunlap's death. After his death, Dunlap's wife discovered a small stack of NSA code word material in the attic of their house and gave it to the Army Counterintelligence agent in charge of the investigation. She did not provide any documents to the NSA.