"NewScientistTech.com" quotes Center for Law and the Biosciences Director and professor Henry T. "Hank" Greely about the the ethics and validity of using brain scans to determine whether or not people are lying.

“I want proof before this gets used, and proof is not three studies of 40 college students lying about whether or not they are holding the three of spades,” says Hank Greely, director of Stanford University’s Center for Law and the Biosciences in California.