Why Famous:Convicted of espionage against his country in 1994, he is serving a life sentence without the possibility of parole.
He was formerly a CIA counterintelligence officer and analyst who committed espionage against his country by spying for the Soviet Union and Russia. It is believed that he compromised the second-largest number of CIA agents in U.S. history.
Dmitri Polyakov
Edward Lee Howard
Ethel Rosenberg
Julius Rosenberg
Kim Philby
William J. Casey