The ability to detect deception is of critical value in criminal and investigative contexts. This study has investigated beliefs about deception detection held by police officers (N = 63) and police students (N = 130). The results show that there are inconsistencies when comparing the beliefs to empirical research findings. One example is the belief that liars avert their gaze. The results are discussed and contrasted with the Truth-Default Theory. Instead of a focus on cues that are probabilisticallyassociated with deception, the Truth-Default Theory focuses on contextualized communication content. The theory recognizes that people are truth biased. Truth-Default Theory proposes that reliance on cues pushes the accuracy of deception detection to the level of chance.