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Mind-set - How bias leads to errors in friction ridge comparisons

NCJ Number
Forensic Science International Volume: 318 Dated: 2021
Date Published

Examples provided in this article are intended to remind friction-ridge examiners to not allow a mind-set to lead them into errors.


“Mind-set” is a term used in the friction-ridge discipline to describe a confirmation bias in which an examiner makes early decisions about their interpretation of a mark but fails to update or reconsider those decisions in light of additional information. This most often occurs during the analysis of a mark when an examiner makes decisions (such as orientation or anatomical source of a mark) to help expedite a manual search or set parameters for an automated search but fails to re-evaluate these decisions if the initial screening of available exemplars does not yield a comparable area, potentially leading to a miss or an erroneous exclusion. Mind-set can also occur when an examiner believes a comparison may be an identification early in the comparison process and employs poor comparison habits to convince themselves it is true, often creating or adapting comparison notes after seeing the exemplar, straining logic to justify their decision, and potentially leading to an erroneous identification. A recent black-box study on palmar comparison accuracy and reliability noted both behaviors in the annotations and notes provided by some study participants. Given the high false-negative error rates reported throughout the literature, examiners need to make re-considering their initial analysis before rendering an exclusion decision part of their comparison routine. (publisher abstract modified)

Date Published: January 1, 2021