Social and Cognitive Factors Affecting Asymmetric Social Hypothesis Testing

The search and evaluation of pieces of evidence for testing alternative hypotheses is a cognitive activity of critical importance in many human domains, including criminal investigations and judgments. The subset of gathered evidences is determined by the information search strategies that are used by the decision maker. However, some highly spontaneous and frequent information search strategies can thwart the hypothesis testing process, causing (over)confirmation biases. The yes-no format of the question is not always a guarantee of effective discrimination between alternative hypotheses. For instance, a dichotomous question can be strongly asymmetric, when affirmative replies are more diagnostic than negative ones (i.e., asymmetric confirming questions, LR(Dh)>>LR(D¬h). Although the modern forensic methodology are particularly careful about procedural accuracy and leading questions, the use of asymmetric-confirming questions could elude the cognitive control and consequently lead to an unconscious confirmation of the focal hypothesis. The present contribution explores cognitive and motivational factors affecting the use of asymmetric questions. Study 1 (N = 253) aimed at exploring if people may have cognitive control over the use of asymmetric strategy. To this goal, specific instructions in order to avoid confirmation tendencies were experimentally manipulated and their efficacy was tested. Study 2 (N = 112) focused on the effect of power on the use of asymmetric strategies. Participants will be placed in more or less powerful position than the social target and their information search process was analyzed. Overall, results showed that, under certain conditions, people may have cognitive control on questions asymmetry and that powerful people are more prone to use asymmetric questions when searching information than weaker persons. Implications for forensic psychology are discussed.