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by donw 2132 days ago
While I totally agree with you, I... have a theory.

It might be psychological warfare.

I would wager that a surprisingly large number of people think that polygraphs detect lies. An even larger number are probably open to the possibility.

If you hook up somebody in that group to a polygraph, you probably rocket their stress levels through the ceiling, which might push them to crack. Behavior under stress is a fascinating thing.

Honestly, I had a snarky comment ready for a comment lower-down about the rationale for polygraphs, but I thought about it a bit, and can't, off the top of my head, come up with a faster, cheaper, and safer way to put that kind of stress on a person.

Useless against somebody trained -- like, say, an intelligence operative -- but it might not be as stupid as it appears on the surface.

2 comments

The Wire has a great scene where they use a photocopier as a fake polygraph to crack a suspect.
I thought this was quite well accepted. I can't speak to the FBI, but for CSIS, the Canadian Equivalent, the "polygraph tech" who pretends to just be working the machine, is actually a psychologist watching your responses.
What's Ironic is some of these agencies that require them for classified information, also teach field operators to evade them. The other fun part about them is when you're in an unclassified situation getting a poly and they're asking questions that if you answer you divulge secrets, if you don't you're lying.

I was once told that I was too calm for my poly and then asked why. My response was I didn't trust the science, or the fact that it was a couple week course. That didn't go over well, I ended up taking two more after that and they gave up.

I've seen the other-side of it though where good people failed their poly because they had too low a baseline like I did, caused by medications.

It's really a bunk science. I can get it as a scare tactic, but the fact the the Govt. still relies on it at a higher level is ridiculous.

> who pretends to just be working the machine, is actually a psychologist watching your responses.

Maybe that's true in Canada (don't know) but it doesn't matter because psychologists are no better at detecting lies than a typical person of similar education, intelligence and age.