The Effect of Rapport Building in Police Interrogations: Can Rapport Improve the Diagnosticity of Confession Evidence?

Police investigators rely heavily on eliciting confessions from suspects to solve crimes and prosecute offenders. Therefore, it is essential to develop evidence-based interrogation techniques that will motivate guilty suspects to confess but minimize false confessions from the innocent. Currently, there is little scientific support for specific interrogation techniques that may increase true confessions and decrease false confessions. Rapport building is a promising possibility. Despite its recommendation in police interrogation guidelines, there is no scientific evidence showing the effect of rapport building in police interrogations. The current study examined, experimentally, whether using rapport as an interrogation technique would influence participants’ decisions to confess to a wrongdoing. It was hypothesized that building rapport with participants would lead to more true confessions and fewer false confessions than not building rapport. One hundred and sixty nine undergraduates participated in the study. Participants worked on logic problems together and individually, with a study confederate. The confederate asked half of the participants for help in one of the individual problems – effectively breaking the rules of the study. After working on these problems, a research assistant playing the role of interviewer came into the room, built rapport or not with participants, accused all participants of cheating by sharing answers on the individual problems, and asked them to sign a statement admitting their guilt. Results indicated that guilty participants were more likely to sign the confession statement than innocent participants. However, there were no significant differences on participants’ confession decisions based on the level of rapport they experienced. Results do not provide support for the hypothesis that building rapport increases the likelihood of obtaining true confessions and decreases the likelihood of obtaining false confessions. These findings suggest that, despite the overwhelming recommendation for the use of rapport with suspects, its actual implementation may not have a direct impact on the outcome of interrogations.