Analysis, Comparison and Evaluation of Latent Prints: The Results of the 2021 Collaborative Exercise of the ENFSI Fingerprint Working Group

In 2021, the Fingerprint Working Group (FIN-WG) of the European Network of Forensic Science Institutes (ENFSI) conducted a collaborative exercise (CE) on the analysis, comparison, and evaluation (ACE) of friction ridge marks. The test proved to be quite challenging, as demonstrated by the high False Negative Rate (FNR = 13.1%). A new category of error was unexpectedly discovered. Two laboratories, while correctly identifying a donor, marked up non-corresponding feature sets to support the identifications. As a result, two false positive rates were calculated, one for source (FPR-1) and one for feature set (FPR-2). FPR-1 was 1.1%, while FPR-2 was 0.7% in this exercise. Additionally, the impact of laboratory approaches to the concept of simultaneity when applied to the lack of continuity of the ridge flow was shown to impact results. Finally, there is also a discussion of the meaning of exclusion given different laboratory approaches.