YAPIŞKAN BANTLARDA GİZLİ PARMAK İZLERİNİN GELİŞTİRİLMESİ

Abstract

In forensic science, fingerprints are considered one of the most reliable forms of physical evidence for identification and criminal investigations. Particularly, making fingerprints visible on adhesive surfaces is defined as a challenging process due to the sticky nature of these surfaces. In this thesis, the effectiveness of the solutions of two new materials was evaluated on different types of adhesive tapes to develop latent fingerprints on adhesive surfaces. In the experimental studies, the capacity of the materials to enhance and preserve fingerprints was analyzed in detail, and the effects of the time elapsed since the fingerprint was deposited on the quality of the print were determined. The first material used in this thesis is fluorescent carbon dots (Material-I), while the second material is an organic molecule with fluorescent properties, 5-chloro-2-(2'- hydroxyphenyl) benzothiazole (Material-II). As adhesive tapes, various types commonly iv encountered in forensic cases were selected, including insulating electrical tape in different colors, transparent packing tape, paper tape, and red silicone tape. The best results with Material-I were obtained on black insulating electrical tape, red silicone tape, and transparent packing tape. Similarly, the best results with Material-II were achieved on black and blue insulating electrical tapes and red silicone tape. It was observed that both materials were more effective in visualizing latent fingerprints on dark-colored tapes compared to light-colored tapes. After the application of the materials, the fingerprints that yielded successful results on the surfaces were tested using the Automated Fingerprint Identification System (AFIS) employed in the Gendarmerie Criminal Laboratories to determine their suitability for practical applications. The system successfully identified the individual who left the fingerprint.