Wired Science

Paul Root Wolpe on Bioethics

What if the fMRI worked perfectly as a lie detector? Wouldn't that be a great thing for courts and cops? What downside could there be to knowing whenever someone isn't telling the truth? Plenty, says Paul Root Wolpe, a professor of bioethics at the University of Pennsylvania.

First off, says Wolpe, a machine that can literally peer inside your head has some ugly implications for privacy and civil liberties. "Everybody wants to know when the murderer or the terrorist is lying," he says. "But there are shades of concern as we move away from the extreme scenarios, which always make bad policy, towards the real way these kinds of things are going to be used. Are employers going to be allowed to use these technologies to screen employees? Is the bank going to be allowed to ask their tellers if they’ve ever stolen anything? If I find a scratch on my car, am I going to be allowed to march my two teenage daughters over to the local fMRI center to find out which one did it?"

Suppose the technology reaches the point where you can be scanned remotely - something researchers are working on. How would you feel, asks Wolpe, about walking through a brain imaging scanner every time an airport security guard asked you what was in your suitcase?

Even in the courts, where separating truth from lies is crucial, the technology raises serious issues, says Wolpe. The Constitution, after all, guarantees a trial by your peers - and unless you're the Bionic Woman, you probably don't consider an fMRI machine your peer. There's good reason to leave it up to juries to separate fact from fiction. "Human beings are so complex and legal situations are so fraught with all kinds of factors that you need humans to decide whether or not other humans are guilty," he says. "Simple truths and simple lies may not always be the issue at stake."

There are times, too, when it's better to lie. "Social lies" are an essential lubricant in our dealings with each other, says Wolpe - "everything from 'you look lovely,' to 'that’s a beautiful baby,' to systems, especially Asian systems, where structured lying is very much a part of how people interact," he says. "If we began to dismantle this extraordinarily complex and historically mediated way that human beings interact, we may do a lot more than figure out who the terrorist is. We may actually damage the very human interaction that we have managed to construct over many centuries.

Photo by Jason Michael