Study on Accuracy of Judgments by Chinese Fingerprint Examiners

The interpretation of fingerprint evidence depends on the judgments of fingerprint examiners.This study assessed the accuracy of different judgments made by fingerprint examiners following the Analysis,Comparison,and Evaluation(ACE)process.Each examiner was given five marks for analysis,comparison,and evaluation.We compared the experts’judgments against the ground truth and used an annotation platform to evaluate how Chinese fingerprint examiners document their comparisons during the identification process.The results showed that different examiners demonstrated different accuracy of judgments and different mechanisms to reach them.

Accuracy and reliability of feature selection by Chinese fingerprint examiners

The selection of minutiae is a critical part of the analysis phase within the fingerprint identification methodology,known as analysis-comparison-evaluation-verification.This study assessed the accuracy and reliability of the minutiae selections of 92 Chinese fingerprint examiners during the analysis phase,absent an exemplar print,of the fingerprint identification process.Specifically,we measured the accuracy(trueness)of their annotation of minutiae,and we measured their reliability which is the reproducibility and repeatability in their annotations in one complex mark by using R software.We observed significant variation within inter-and intra-examiner annotations of the minutiae.We saw no statistically significant differences for the variability of minutiae annotations based on the participant’s sex or years of experience.

Detecting Latent Prints on Stone and Other Difficult Porous Surfaces via Indanedione/Zinc Chloride and Laser

Lasers and alternate light sources have been recognized as effective tools for latent print detection for over three decades.Luminescence often increases friction ridge contrast to reveal impressions otherwise undetectable.Indanedione/zinc chloride excited by a forensic light source is widely recognized as an effective process for developing latent prints on porous surfaces.This study was designed to evaluate the use of a combination of luminescence excitation and indanedione with zinc chloride to detect latent prints on stones,bricks,and similar difficult porous surfaces.The wavelengths evaluated included 400 nm(violet),447 nm(blue),532 nm(green),and 645 nm(red).Latent prints were deposited on a variety of porous surfaces including bricks,cement stones,wood,and cotton fabric,all commonly encountered at crime scenes in China.The surfaces were examined using white light(light‑emitting diode flashlight)and laser light sources separately,both before and after treatment with indanedione/zinc chloride.The goal of this study was to evaluate various light sources for their effectiveness in detecting impressions developed by indanedione/zinc chloride on difficult porous surfaces.Results indicated that latent prints on some brick and cement stone surfaces may be effectively detected using 532 nm laser excitation after indanedione/zinc chloride processing.

Development of Quality Control System for Fingerprint Comparison Processes

Fingerprint evidence played an important role in investigation,prosecution,and trial process due to the belief of its uniqueness and unchanged characteristics.However,in recent years,the science behind the process of fingerprint comparisons has been questioned.Main research questions have been focusing on the opaqueness within the comparison processes,subjective judgments,lack of universal standards,no error rate expression on final conclusions,and poor scientific fundamental research data.Facing the above-mentioned questions,this paper aims to suggest a quality control system(QCS)for fingerprint comparison processes.This QCS is based on the use of software(PiAnoS)and its technological features,being able to provide a data management model to increase the transparency and quality of fingerprint comparison processes.