[discostu]

How many big time leaks and outright spies have they had since instituting the polygraph testing? Doesn't seem like they've been using them successfully to me. I doubt they think it's reliable, they just don't have anything better. Not having something to hide is no garauntee of passing a polygraph, that's the big lie of the polygraph companies.

[garbageseeker]

How many big time leaks and outright spies have they had since instituting the polygraph testing?

That is why you have regular examinations to prevent cheating. Again, its not perfect, but its still reliable enough to warrant further investigation of the subject if the test comes out negative. There are no guarantees in life.