Allegiance Bias in Statement Reliability Evaluations is not Eliminated by Two-Sided Instructions

We examined this issue by having students act as expert witnesses in evaluating interviews in a child sexual abuse case (Experiment 1, N = 143) and tested the value of an instruction to counteract such allegiance effects. The intervention concerned an instruction to consider arguments both for and against the given hypothesis (i.e., two-sided instructions; Experiment 2, N = 139).

In Experiment 3 (N = 123), we additionally provided participants with three different scenarios. Participants received a case file regarding a case of alleged sexual abuse. With the file, participants received an appointment letter emphasizing elements of the file that questioned (defense) or supported (prosecution) the veracity of the accusation.