Applying Deception Detection to True and False Confessions: A Novel Approach to Conducting Experiments in Legal Psychology

Abstract

Recent exonerations of convicted defendants by the efforts of advocates like the Innocence Project are accompanied by a concerning finding that a large proportion of defendants had falsely confessed to the alleged crime. False convictions result in due process violations and the suffering and stigma of the convicted and their families, in addition to imposing an economic burden on the community. Prior research has identified structural interrogation practices and individual characteristics that increase risk of false confessions, however knowledge on how to identify true and false confessions is minimal and undeveloped. Cues to deception in false statements may be an effective means of identifying true and false confessions. However, extant research on deception detection has not been fully applied to confessions and paralinguistic cues (e.g. pauses, pitch change) have never been tested. This study examined the efficacy of training in paralingustic cues on the ability to identify true and false confessions. A second goal was to assess the use of an online experimental survey as an alternative to traditional experiments. True and false confessions to guilt-inducing or shame-evoking events were obtained through an adaptation of Kassin, Meissner, & Norwick’s (2005) method. Participants (n = 63) from a second sample were randomly assigned to receive training in paralingustic cues to deception or a placebo training. Subsequently, participants rated perceived veracity of six confessions and their confidence level in each judgment. Consistent with prior research, the results indicated that accuracy rates were around chance levels and that confidence was not related to accuracy. The accuracy rate of the paralingustic group did not significantly differ from the control group, possibly due to random effects in treatment assignment. The paralingustic group indicated significantly higher confidence than the control group, which highlights a troubling trend that deception detection training increases confidence, but not accuracy in judgment. It is essential for agents in the legal system - law enforcement, legal decision-makers, and psychologists - to be aware of cues to guilt or innocence in confessions, along with risk factors for false confessions, in order to prevent false convictions and preserve the legitimacy of the legal system.