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Occurrence and Utility of Latent Print Correspondences That Are Insufficient for Identification

NCJ Number
255634
Date Published
October 2020
Length
91 pages
Author(s)
David A. Stoney; Paul L. Stoney
Agencies
NIJ-Sponsored
Publication Type
Research (Applied/Empirical), Report (Technical Assistance), Report (Study/Research), Report (Grant Sponsored), Program/Project Description
Grant Number(s)
2016-R2-CX-0060
Annotation
This research project examined whether latent fingerprints with discernible but insufficient characteristics for identification could provide associative evidence that contributes to an investigation.
Abstract
Non-identifiable fingermarks (NIFMs) from casework were collected from nine jurisdictions in the United States. All of these prints had been determined by experts to fall below the threshold "of value for identification;" however, they had some clear Level 2 detail (three or more minutiae) within an area of contiguous ridge flow. Expected score-based likelihood ratios (ESLRs) were measured, based on modeling within-variability and between-variability of AFIS scores. This method incorporated latest-generation feature extraction, a (minutiae-only) matcher, validated distortion functions, and NIST SD27 database calibration. Out of 1,668 fingermark images, screening to remove potentially identifiable prints and those with less than three minutiae left 750 NIEMs. The reported analytical method indicated that the strength of association would be the same as for an event occurring one time in 380,000. The results indicate that NIFMs commonly occur and that they offer the prospect of strong associative evidence. It can support or refute the identity of a person touching a surface, provide evidence that supports the identity of a person present at a location, and provide evidence that supports the involvement of an individual in an activity. It can be included with other facts in a case to show when a surface was touched, or to improve or diminish the credibility of other evidence. Overall, there is high potential for the beneficial investigative and prosecutorial use of this frequently occurring type of physical evidence, and it requires minimal additional analysis to implement. Priority next steps in moving toward the implementation of NIFM evidence are suggested. 39 figures, 4 tables, and 43 references
Date Created: November 9, 2020