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Why Experts Make Errors

NCJ Number
Journal of Forensic Identification Volume: 56 Issue: 4 Dated: July/August 2006 Pages: 600-616
Itiel E. Dror; David Charlton
Date Published
July 2006
17 pages
This study examined whether expert latent fingerprint examiners would reach the same conclusions about latent print comparisons when they re-examined them at a later time believing them to be new cases.
For 48 experimental trials, the fingerprint experts changed their previous decisions on six pairs of fingerprints. Only one-third of the experts (two out of six) remained completely consistent across the trials. Inconsistent decisions were most common with difficult decisions and when the expert was given additional information about the case, such as corroborative or conflicting evidence or a confession. The inconsistencies observed in this study are attributed to the human limitations associated with human psychological characteristics and cognitive features. One of the most notable characteristics of humans is the active and dynamic nature of our processing of information. Although humans can process and analyze vast amounts of information, a multitude of variables influence how we evaluate visual information and make decisions. Previous research has shown that under conditions of relatively extreme and rare variations in the context for fingerprint analysis, fingerprint experts may change the way they compare and judge fingerprints. Future research may be able to identify the personal characteristics or analytical procedures of experts who are consistent in their fingerprint analyses. This information could assist in training all experts to improve the consistency of their analyses. The six expert latent fingerprint examiners were presented with fingerprints taken from real criminal cases. Half of the prints had been previously judged as matches and the other half as exclusions. These prints were resubmitted to the same experts who had judged them previously, but with the addition of biasing case information for the cases. A control set of matches and exclusions was also represented to the experts as part of the study. 1 table, 2 figures, and 14 references