Abstract
This study is a quasi-experiment focusing on the deception detection ability of prison inmates (n=52) and college students (n=52). Participants made veracity judgments of videotaped statements of witnesses either lying or telling the truth about an event. In line with findings on criminals' beliefs about cues to deception, it was predicted that prison inmates would outperform students in terms of lie detection accuracy. Our hypothesis received partial support since the prison inmates outperformed the students in terms of detecting lies, but not in terms of detecting truths. Moreover, the prison inmates achieved an accuracy level higher than chance, while students did not. Furthermore, prison inmates had a pronounced lie bias. It is possible that the outcome feedback provided in the environment of criminals may explain the differences in accuracy levels between prison inmates and students. It is suggested that relevant outcome feedback may be a beneficial component in training of professional lie-catchers in order to improve their performance.
Thanks are due to Mattias Guldstrand and Markku Roitto for help with the collection of data.