Back in college, there was this guy with a little software company in his three-story house. Really scummy owner, and I don't know the half of how scummy, but he'd throw a dinner party every Thursday. Some weird coincidences about those parties, but nothing I want to get into right now.
The dinners were delicious. Really innovative, and, if you're a college student, that's a big motivation. On top of that, the tabletops were covered with butcher paper and there were crayons around, which makes the whole thing even more delicious.
So one time it was getting pretty late, and I think the owner guy was drunk, and he started bragging about one job he got from the government. I don't know if the story's true or not, but here's what he said to the assembled.
The owner said that original lie detectors had a problem. I put forward that the problem was that the tests were unreliable, but the owner dismissed my comment (as he usually did). Instead, he said the problem was that all a lie detector would do was evaluate whether an answer's true or false. They could find where something is by showing them maps and asking yes/no questions, but there was a lot of information you just couldn't get.
So a group of psychologists from some intelligence service looked into it, and developed a set of rules. Some fifteen rules or something, and if you asked a question using those rules, people would decide to answer honestly. So they contracted this little software company to do the job - my host's company, or so he said - and they implemented these rules in software. Apparently, they tested it; they had a bunch of students from the local Catholic school come out to the machines, and sat them down. They got all kinds of confessions and answers and everyone was satisfied that it worked. Apparently, that was the end of it. Contract successful.
I asked the company's owner about the moral implications of this, and he gave me a dry, dead stare, heavy with reptilian contempt.