FIGURE 9.14 How often do lie detectors lie? In one study, polygraph experts interpreted the test results of 100 people who had been suspects in theft crimes (Kleinmuntz & Szucko, 1984). Half the suspects were guilty and had confessed. The other half had been proven innocent. If the polygraph experts had been the judges, more than one-third of the innocent would have been declared guilty, and one-fourth of the guilty would have been declared innocent.