Effects of questioning styles and defendant’s intellectual disability on the public perceptions of a police interview and guilty verdict

Abstract

This study examined how the public perceives interview styles and investigated the effects of a defendant’s intellectual disability on perceptions of a police interview and decisions about guilt. An online survey was administered to 841 members of the general public, who were presented with a fictional arson case and one of two different interviews, one ‘open-ended’ and the other ‘closed-ended’. Half of the participants received a description of a defendant with an intellectual disability. Participants believed that the open-ended interview was fairer, and that the defendant’s confession elicited through this interview was more voluntary, truthful and credible. Questioning style did not influence participants’ decisions about guilt, but the perception of the interview and confessions mediated between interview style and their decisions. Thus, interviewers are recommended to use open-ended questions during suspect interviews, not only to obtain information, but also to ensure that their confessions are admitted in court.