Applying Hierarchy of Expert Performance (HEP) to investigative interview evaluation: strengths, challenges and future directions

When the Evidence Is Incorrect: an Exploration of What Happens When Interviewers Unwittingly Present Inaccurate Information in Interviews with Suspects

Skillfully presenting evidence/information to suspects is one of the few interviewing techniques that increases the likelihood of guilty suspects providing information or making a confession, without making innocent ones do so as well. It is important that this evidence/information is correct, since deliberately disclosing incorrect evidence poses some risks. Also, in real-life interviews, police interviewers may unwittingly disclose incorrect evidence, for example when a witness was mistaken and provided the police with incorrect information. The present study examined the behavior of fifty police interviewers in interviews with "suspects" of a scripted crime: what is their response when the interviewees try to explain to them that some of the evidence/information just disclosed by them is incorrect? Eleven interviewers responded adaptively (by actively picking up on this new information), 35 responded in a neutral way and four responded maladaptively (by discrediting the interviewee's claim). Experience and a full interview training had a significant negative relationship with adaptiveness. These results indicate that, when preparing and conducting interviews with suspects, greater awareness is needed of the possibility that some of the evidence/information that is to be disclosed could be incorrect, and therefore it is crucial that suspects' responses which suggest such may be the case are taken into account.

A hierarchy of expert performance as applied to forensic anthropology

Due to their medicolegal repercussions, forensic anthropology conclusions must be reliable, consistent, and minimally compromised by bias. Yet, a synthetic analysis of the reliability and biasability of the discipline's methods has not yet been conducted. To do so, this study utilized Dror's (2016) hierarchy of expert performance (HEP), an eight-level model aimed at examining intra- and inter-expert reliability and biasability (the potential for cognitive bias) within the literature of forensic science disciplines. A systematic review of the forensic anthropology literature was conducted (1972-present), including papers published in the American Journal of Physical Anthropology, Forensic Anthropology, Forensic Science International, and the Journal of Forensic Sciences and Anthropology Section abstracts published in the Proceedings of the Annual Meeting of the AAFS which matched keywords such as "forensic anthropology," "bias," "reliability," "cognition," "cognitive," or "error." The resulting forensic anthropology HEP showcases areas that have ample research and areas where more research can be conducted. Specifically, statistically significant increases in reliability (p < 0.001) and biasability (p < 0.001) publications were found since 2009 (publication of the NAS report). Extensive research examined the reliability of forensic anthropological observations and conclusions (n = 744 publications). However, minimal research investigated the biasability of forensic anthropological observations and conclusions (n = 20 publications). Notably, while several studies demonstrated the biasing effect of extraneous information on anthropological morphological assessments, there was no research into these effects on anthropological metric assessments. The findings revealed by the forensic anthropology HEP can help to guide future research, ultimately informing the development and refinement of best-practice standards for the discipline.

Expert Reliability in Legal Proceedings: "Eeny, Meeny, Miny, Moe, With Which Expert Should We Go?"

Between Expert Reliability refers to the extent to which different experts examining identical evidence make the same observations and reach the same conclusions. Some areas of expert decision making have been shown to entail questions with relatively low Between Expert Reliability, but the disagreement between experts is not always communicated to the legal actors forming decisions on the basis of the expert evidence. In this paper, we discuss the issues of Between Expert Reliability in legal proceedings, using forensic age estimations as a case study. Across national as well international jurisdictions, there is large variation in which experts are hired to conduct age estimations as well as the methods they use. Simultaneously, age estimations can be fully decisive for outcomes e.g. in asylum law and criminal law. Using datasets obtained from the Swedish legal context, we identify that radiologists and odontologists examining knees or teeth images to estimate age seem to disagree within their own disciplines (radiologist 1 v. radiologist 2 or odontologist 1 v. odontologist 2) as well as across different disciplines (radiologist v. odontologist) relatively often. This may have large implications e.g. in cases where only one expert from the respective field is involved. The paper discusses appropriate ways for legal actors to deal with the possibility of lacking Between Expert Reliability. This is indeed a challenging task provided that legal actors are legal experts but not necessarily scientific experts.

Biasability and reliability of expert forensic document examiners

The performance of experts can be characterized in terms of biasability and reliability of their judgments. The current research is the first to explore the judgments of practicing forensic document experts, professionals who examine and compare disputed handwritten evidence to handwriting exemplars of individuals involved in criminal or civil litigation. Forensic handwriting experts determine if questioned and known handwritten items are of common authorship or written by different individuals, and present their findings in legal proceedings. The expert participants in our study (N=25) were not aware that they were part of a research study. Thirteen participants were led to believe that they were working on a case commissioned from the prosecution and the other twelve that it was for the defense. We did not find evidence in this study that this information biased their judgments, which may make sense since document examiners (in contrast to many other forensic domains) do not primarily work within an organizational forensic laboratory culture. The lack of bias in our findings may have been also due to the stimuli we used or/and the great variability in the judgments within each group, reflecting a lack of consistency in conclusions among examiners. A detailed discussion of our findings is presented along with the limitations that may have affected our results.