"One thing E.R.P. might eventually be able to do is predict whether someone intends to lie — even before he or she has made a decision about it."

NYT: The study of deception. Dr. Jennifer Vendemia discusses her work with event-related potentials:

...This brings us into sci-fi territory, into the realm of mind reading. When Vendemia has a subject in an E.R.P. cap, she can detect the first brain-wave changes within 240 to 260 milliseconds after a true-false statement appears on a computer screen. But these changes are an indication of intention, not action; it can take 400 to 600 milliseconds for a person to decide whether to respond with 'true' or 'false.' 'With E.R.P., I've taken away your right to make a decision about your response,' Vendemia said. 'It's the ultimate invasion.' If someone knows before you do what your brain is indicating as your intention, is there any room left, in that window of a few hundred milliseconds, for the exercise of free will? Or have you already been labeled a liar by your spontaneous brain waves, without your having a chance to override them and choose a different path?

Lies make secrets possible; they let us carve out a private territory that no one, not even those closest to us, can enter without our permission. Without lies, there can be no such sanctuary, no interior life that is completely and inviolably ours. Do we want to allow anyone, whether a government interrogator or a beloved spouse, unfettered access to that interior life?"