Meta‐analytically Quantifying the Reliability and Biasability of Forensic Experts
- 4 July 2008
- journal article
- research article
- Published by Wiley in Journal of Forensic Sciences
- Vol. 53 (4), 900-903
- https://doi.org/10.1111/j.1556-4029.2008.00762.x
Abstract
In this paper we employ meta‐analytic procedures and estimate effect sizes indexing the degree of reliability and biasability of forensic experts. The data are based on within‐expert comparisons, whereby the same expert unknowingly makes judgments on the same data at different times. This allows us to take robust measurements and conduct analyses that compare variances within the same experts, and thus to carefully quantify the degree of consistency and objectivity that underlie expert performance and decision making. To achieve consistency, experts must be reliable, at least in the very basic sense that an expert makes the same decision when the same data are presented in the same circumstances, and thus be consistent with themselves. To achieve objectivity, experts must focus only on the data and ignore irrelevant information, and thus be unbiasable by extraneous context. The analyses show that experts are not totally reliable nor are they unbiasable. These findings are based on fingerprint experts decision making, but because this domain is so well established, they apply equally well (if not more) to all other less established forensic domains.Keywords
This publication has 7 references indexed in Scilit:
- Contextual information renders experts vulnerable to making erroneous identificationsForensic Science International, 2006
- Perception is far from perfection: The role of the brain and mind in constructing realitiesBehavioral and Brain Sciences, 2005
- requivalent: A simple effect size indicator.Psychological Methods, 2003
- The Counternull Value of an Effect Size: A New StatisticPsychological Science, 1994
- Visual-spatial abilities of pilots.Journal of Applied Psychology, 1993
- Meta-Analytic Procedures for Social ResearchPublished by SAGE Publications ,1991
- A simple, general purpose display of magnitude of experimental effect.Journal of Educational Psychology, 1982