Lie Detector for Welfare Cheats?

For many years, critics of lie detectors have assailed the United States for being one the few countries to be totally snookered by the dubious science of the lie detector. The U.K. isn't that far behind. It now appears the U.K. government is jumping on the bandwagon, but not for national security---officials there want to root out would-be welfare scammers:

*Under proposals announced by the Department for Work and Pensions, benefit claimants would be assessed during phone calls by software that claims to be able to tell if they are lying about their status. *

The government said that a positive result will spark an investigation. But the plans have drawn sharp criticism from opposition parties and unions.

A major study here in the U.S. found "only limited scientific evidence for establishing the validity of polygraph testing," and concluded that "[e]ven where the evidence seems to indicate that polygraph testing detects deceptive subjects better than chance (when using the control question technique in specific-incident criminal investigations), significant error rates are possible, and examiner and examinee differences and the use of countermeasures may further affect validity."