From the late Middle Ages through the eighteenth century, the science of physiognomy played a central role in the intellectual life of what we might call “the long Renaissance.” Indeed, it did much to shape both the portrayal and the understanding of personality in the visual and literary arts of the period. But nowhere was its influence greater than in the practice of criminal law. This special issue explores the varied ways that jurists and judges drew on theories—ancient and modern—of how to read the human body, the face especially, in order to help determine whether or not a suspect was guilty or innocent. The articles offer insights into the various ways in which Renaissance thinkers not only drew on ancient and medieval sources for their understanding of human psychology but also continued to elaborate new theories in order to develop what they viewed as a more scientific jurisprudence.