"Project Slammer, now partially declassified, was based on extensive prison interviews with some 30 former military and intelligence personnel who had been convicted of spying for Russia, China and other hostile powers during the Cold War, from the lowest enlisted men to senior CIA officers like Aldrich Ames. It sought to answer why they had violated the trust their agencies had bestowed on them.
[...] the authors of the highly classified Project Slammer report, delivered to CIA management on April 12, 1990, emphasized that behavioral changes were often associated with acts of espionage.
“The authors believe that if co-workers and bosses could be educated to intervene with a troubled employee early on, damaging espionage might be prevented.” [...]
The Project Slammer report said it was "not possible to determine whether employee assistance, private counseling or other therapeutic applications would have made a significant difference ..." But it pointed out that no traditional counterintelligence methods -- background investigations, lie detectors, surveillance -- worked either."
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*MICE: Money, Ideology, Coercion, Ego