Tecnologias da mentira são... mentira?

Polygraphs and other lie-detection technologies may never really work in the real world: As far as detecting actual lies, however, polygraphs produce too many false positives—that is, they mistake too many truthful people for liars. In the eyes of a lie-detector examiner, innocent people can seem guilty. Under interrogation, they may become frightened, indignant, or agitated. Their hearts pound, their breath labors, and their palms sweat. They may even feel guilty. Conversely, liars are not necessarily anxious; this is especially true of psychopaths and other practiced liars, whose peripheral nervous systems are less responsive to threat than are most individuals’. At bottom, the polygraph is an arousal detector, not a lie detector.