Professor Hank Greely is quoted in The New Yorker on the validity of brain scans as lie-detection devices:

Legal scholars, for their part, have started debating the constitutionality of using brain-imaging evidence in court. At a recent meeting of a National Academy of Sciences committee on lie detection, in Washington, D.C., Hank Greely, a Stanford law professor, said, “When we make speculative leaps like these . . . it increases, sometimes in detrimental ways, the belief that the technology works.” In the rush of companies like No Lie to market brain scanning, and in the rush of scholars to judge the propriety of using the technology, relatively few people have asked whether fMRIs can actually do what they either hope or fear they can do.