Previously identified neural correlates of deception, such as the prefrontal, anterior cingulate and parietal regions, have proven to be unreliable neural markers of deception, most likely because activity in these regions reflects executive processes that are not specific to deception. Herein, we report the first fMRI study that provides strong preliminary evidence that the neural activity associated with perception but not executive processes could offer a better marker of deception with regard to face familiarity. Using a face-recognition task, activity in the left precuneus during the perception of familiar faces accurately marked 11 of 13 subjects who lied about not knowing faces that were in fact familiar to them. This level of classification accuracy is much higher than the level predicted by chance and agrees with other findings by experts in lie detection. Copyright © 2013 Nature Publishing Group.