In a recent post, we reported that convicted spies Aldrich Ames and Robert Hanssen both passed polygraph tests during their careers at the CIA and FBI, respectively. Actually, Ames was allowed to continue in his post, despite "questionable" polygraph results. Hanssen, on the other hand, was never polygraphed during his FBI career, spent mostly in the bureau's counter-intelligence division.
We were accurate in noting that both Ames and Hanssen were familiar with techniques for defeating lie detector tests. Those skills--coupled with the "old boy" network at Langley--helped Ames continue his traitorous deeds well into the 1990s, compromising numerous CIA assets inside the former Soviet Union. The FBI's failure to polygraph Hanssen also helped perpetuate his spy career--and it's a big reason that all agency employees now take lie detector tests, on a recurring basis.