Research by social psychologists and others consistently finds that people are poor at detecting attempted deception by others. However, Tooby and Cosmides (cognitive psychologists who favor evolutionary analyses of behavior) have argued and shown that humans have evolved a special “cognitive module” for detecting cheaters. Their research suggests that people are good at detecting cheating by group members. These two literatures seem to be at odds with one another. The hypothesis of this research was that when participants are told a lie by a fellow group member whose attempted deception involves cheating on a task that affects their outcomes, they will be good at detecting deception. In this experiment, participants played blackjack in groups using a social dilemma paradigm. Participants’ outcomes were either interdependent or independent with a confederate’s outcomes. It was predicted that participants whose outcomes were interdependent with the confederate would be better at detecting deception by the confederate than those participants whose outcomes were independent from the confederate’s outcomes. Results indicate that when judging other participants’ lies interdependent players were more successful at deception detection than independent players but were not more sensitive to the lies. This effect may be driven by the truth bias, people assume that their interaction partners are truthful which would explain why sensitivity measures (which remove response biases) did not show the hypothesized effect. Independent players were not more successful or sensitive when judging the confederate’s lies. The failure to find the hypothesized effect may be due to methodological factors. Both participants heard may have had their cheating detection modules activated when hearing the instructions for the experiment which implied that cheating could occur. Overall success rates support this idea because they were significantly higher than success rates reached by most deception detection research (50%) which may be indicative that both participants cheating detection modules were active. Results also indicate that as the number of lies told increases overall success decreases but success at detecting lies and sensitivity increase. Thus the more lies that are told the better people are at catching them
