Steve Silberman (my favorite Wired Magazine investigative reporter) has a fascinating and disturbing feature out in this month's issue about lie-detection using functional MRI (fMRI) devices that detect physiological changes in the brain brought on by prevarication.
The story is fascinating in that the science of lie-detection with fMRI is part of a wave of new technologies arising on the back of fMRI's ability to observe brains at work in a wide variety of tasks, deepening our understanding of what's going on in our own hands.
But it's disturbing in the callous attitude of the companies that are commercializing the technologies to civil liberties — one of them gives a backhanded endorsement to Guantanamo Bay detentions ("If these detainees have information we haven't been able to extract that could prevent another 9/11, I think most Americans would agree that we should be doing whatever it takes to extract it").
Likewise disturbing is the casual interpretation of the Constitution offered by the Center for Democracy in Technology (an organization known for offering "compromise positions" on civil liberties issues) who propose that you grant "consent" to invasions of your privacy when you are coerced into doing so by the threat of police harassment if you decline.
Present-day lie-detection via polygraph is pure junk science, an abusive technology badly in need of replacement. fMRI might offer a superior mechanism for uncovering the truth, but the social harm that could arise from being compelled to testify against yourself, from being compelled to submit your mental state to coercive oversight are truly frightening.
After taking a job at the University of Pennsylvania School of Medicine later that year, he mapped the brains of undergraduates who had been instructed to lie about whether a playing card displayed on a computer screen was the same one they'd been given in an envelope along with $20. The volunteers – who responded by pressing a button on a handheld device so they wouldn't have to speak – were told that if they "fooled" the computer, they could keep the money. Langleben concluded in 2002 in a journal called NeuroImage that there is "a neurophysiological difference between deception and truth" that can be detected with fMRI…
The introduction of fMRI evidence at trial may have to be vetted against legal precedents designed to prevent what's called invading the province of the jury, says Carter Snead, former general counsel for the President's Council on Bioethics. In 1973, a federal appeals court ruled that "the jury is the lie detector" and that scientific evidence and expert testimony can be introduced only to help the jury reach a more informed judgment, not to be the final arbiter of truth. "The criminal justice system is not designed simply to ensure accurate truth finding," Snead says. "The human dimension of being subjected to the assessment of your peers has profound social and civic significance. If you supplant that with a biological metric, you're losing something extraordinarily important, even if you gain an incremental value in accuracy."