Research on the detection of deception through nonverbal cues has shown that people's ability to discriminate between truth and deception is only slightly better than chance level. One of the reasons for these disappointing findings possibly lies in people's inappropriate beliefs regarding "lying behavior." A 64-item questionnaire originally used in Germany, which targets participants' beliefs regarding truthful and deceptive behavior, was used. Data from the completed questionnaires of 120 participants, 60 police officers and 60 lay people, were analyzed in the study. The study differed from previous research in three ways. First, instead of a student population, police officers and lay people were sampled. Second, both people's beliefs regarding others' deceptive behavior and their beliefs regarding their own deceptive behavior were examined; and third, both nonverbal cues to, and content characteristics of, deceptive statements were examined. Results were consistent with those of previous studies, which found significant differences between people's beliefs regarding deceptive behavior and experimental observations of actual deceptive behavior. Further, police officers held as many false beliefs as did lay people. Finally, participants were more accurate in their beliefs regarding their own deceptive behavior than they were in their beliefs regarding others' behavior. 1 table and 29 references