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.
Two of the most important factors in a mole’s decision to steal secrets... emotional distress, and lax security...
...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.
“Heavy drinking, drug dependence, signs of depression or stress, extramarital affairs and divorce could be warning signs of a security problem...” (more)
What type of person is pre-disposed to becoming a spy?