Preliminary efficiency evaluation of development methods applied to aged sebaceous latent fingermarks

Area of Science:

• Forensic Science
• Trace Evidence Analysis
• Biochemistry

Background:

• Latent fingermarks are crucial for criminal identification.
• The chemical composition of fingermarks degrades over time, impacting their detectability.
• Understanding fingermark aging is vital for optimizing forensic analysis.

Purpose of the Study:

• To analyze the fatty acid profile of sebaceous latent fingermarks.
• To evaluate the effectiveness of different fingermark enhancement methods over a 30-day aging period.
• To correlate changes in fingermark composition with the efficacy of development techniques.

Main Methods:

• Gas Chromatography-Flame Ionization Detection (GC-FID) for fatty acid profiling.
• Controlled aging of fingermarks under specific temperature, photoperiod, and humidity.
• Assessment of powder dusting, iodine fuming, and silver nitrate methods for fingermark development.

Main Results:

• Significant variations in myristic, palmitic, stearic, and oleic acid levels were observed over 30 days.
• Fluorescent orange powder and silver nitrate methods showed increased efficacy with fingermark aging.
• Iodine fuming's efficiency decreased over time, while silver black powder remained constant.

Conclusions:

• Fingermark aging alters fatty acid composition, influencing the performance of development techniques.
• The study provides insights into the kinetics of fingermark aging and its impact on forensic identification methods.
• Optimized use of fingermark enhancement techniques can be achieved by considering aging effects.