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Weekend reading and listening: lie detection

This past week NPR's Morning Edition carried a three-part series about lie detection reported by Dina Temple-Raston. (The segments are posted as both audio and text, so they're easy to scan if you can't listen.) The series covers the questionable accuracy of polygraphs, the emerging field of lie detection by fMRI, and the examination of facial "micro expressions" for hints of lies.

One of the most interesting ideas in the series is that these new techniques for lie detection just seem more modern and scientific. From that second segment about fMRI:

Nathan was accused of setting fire to his restaurant in 2003. A judge eventually dismissed the charges, but Nathan's insurance company wouldn't pay up. Nathan read about the fMRI in the newspaper and thought it could provide proof positive that he had nothing to do with the deli fire.

Nathan had thought about subjecting himself to a polygraph, but experts he talked to said the machine was too unpredictable and could end up indicating he was lying even when telling the truth. Most courts don't view the polygraph as a scientific test, so taking one — and getting some inconclusive result — wasn't worth the risk, Nathan concluded.

Because the fMRI seemed more scientific, last year Nathan flew to California to climb into the No Lie fMRI and answered questions about the fire. The scan indicated that he wasn't lying and passed the test.

"If I hadn't passed, I would have jumped from the 17th floor window of the hotel where I was staying," Nathan said. "How could I have gone back to South Carolina if I hadn't passed?"

Buoyed by the results of the brain scan, Nathan said he is planning to do two more with other companies. He also plans to go for a polygraph test.

The problem with all this, of course, is that there's not a whole lot of good data indicating that these new techniques actually are better and more accurate. They could be, but there's still a lot research that needs to be done.

It will be interesting to see how quickly these new approaches filter into the popular consciousness -- and whether that awareness arrives before the data backing up the techniques. Who wants to bet Jack Bauer puts a terrorist in a scanner next season on 24?*

By the way, if all this seems familiar, there was a story in the New Yorker this past summer that covered much of the same ground. That article even included a reference to AJOB. And in the NPR series, be sure to catch the comments by Paul Root Wolpe.

-Greg Dahlmann

*Not that this would work. As Temple-Raston notes in her series, even the slightest of movements can throw off a scan, so it would make scanning a hostile or uncooperative subject very difficult.