ObjectivesStrategic questioning and disclosure of evidence are increasingly recommended as empirically-supported techniques in interviews. To date, no research has evaluated how different types of evidence (e.g., eyewitness, fingerprints) might affect interview outcome. HypothesesWe hypothesized that suspects would be more willing to make statements that contradict pieces of evidence that are perceived to be weaker and less reliable.MethodsIn Study 1, we conducted systematic and meta-analytic reviews of the literature to retrospectively assess these factors. In six experiments, we began to fill this gap by manipulating strength and reliability of evidence (Study 2, 3c, and 4a), assessing the validity of our operationalizations (Study 3a-b) and testing generalizability across operationalizations (Study 3c), and examining participants’ rationale for their responses to a qualitative analysis (Study 4b). ResultsStudy 1 found that evidence type and, hence, reliability had not been taken into account in previous research. Further, we were unable to establish if observed effects of interview tactics were moderated by the properties of the evidence used. In Study 2, we found that participants were more consistent with evidence when it was more reliable, especially when it was highly incriminating. After validating our operationalizations in studies 3a and 3b, we replicated the pattern found in Study 2 (3c and 4a), whereby those in the highly reliable condition were most consistent with the evidence, followed by those with less reliable evidence and no evidence.ConclusionsWe demonstrated that evidence properties should be considered when studying how to disclose information in an investigative interview.

Objective: The Shift-of-Strategy (SoS) approach is an extension of the Strategic Use of Evidence technique. In the SoS approach, interviewers influence suspects’ strategies to encourage suspects to become more forthcoming with information by challenging discrepancies between their statements and the available evidence, in a non-accusatory manner. Our aim was to test the effectiveness of two variations of the SoS approach, one in which the interviewer responded immediately to any discrepancies with the evidence (Reactive) and one in which the interviewer only responded to severe discrepancies (Selective).Hypotheses: We generally predicted that the SoS approach conditions would be more effective at eliciting new information from mock suspects, compared to direct questioning.Method: In a laboratory experiment, N = 300 mock suspects committed a simulated crime and were interviewed using one of the two versions of the SoS approach or with an interviewing approach that did not involve the presentation of evidence. We coded the transcribed interviews to assess how much information about the mock crime participants disclosed.Results: The Reactive version of the SoS approach was more effective than direct questioning at eliciting new information from mock suspects. The Reactive technique also appeared to prompt participants to change their strategies during the interview.Conclusions: The present experiment provides initial support for the core principles of the SoS approach.