Efeito das variações temporal e de intempéries sobre a detecção de marcas papilares latentes por tecnologia contactless

Abstract

Fingerprint analysis is routinely used for forensic human identification, but in the case of latent marks, estimating their permanence becomes a challenge for criminal investigation. This study aims to evaluate the relationship between the aging of latent fingerprints (LFD) when exposed to open air and in total darkness. Samples were obtained from 12 volunteers (5 men and 7 women), aged between 21 and 46 years, and 3 LFDs were collected on glass slides from the right index finger of each individual, totaling 36 samples. The prints were distributed equally between the control, ambient and darkness groups. The temperature and relative humidity of the air were recorded weekly for 6 weeks. In addition, the latent prints were photographed by a Mobile Non-Contact Multispectral Fingerprint Detection System - ForenScope®. Two trained fingerprint experts analyzed the conditions under which the photographs were compared, applying the criteria of the ACE-V method (Analysis, Comparison, Evaluation and Verification). The images were then imported without treatment into the Automated Fingerprint Identification System (SAIID). A score generated by the software, reflecting the average quality of the IDL minutiae, was also recorded weekly. The R Core Team 4.1.1 software was used for statistical analyses. Throughout the study, humidity ranged from 65% to 85% and temperature from 22.1°C to 24.1°C. The correlation coefficient based on the SAIID scores between the groups was 1.000. The average number of days that an IDL remained in confrontation conditions for the SAIID was 13 days in the ambient group and 25 days in the dark group. 66.67% of the samples in the ambient group lost confrontation conditions in the first week of evaluation. In contrast, all IDL in the dark group were in identification conditions during this period. No statistically significant difference was observed between the SAIID scores from weeks 0 to 4 between the groups. Furthermore, there was no inversely proportional pattern between the SAIID score and the aging of the print throughout the research. Furthermore, the distribution of the data did not allow the establishment of a reliable linear regression model.