Investigations into the Influence of Donor Traits on the Performance of Fingermark Development Reagents. Part 1: 1,2-Indanedione-Zinc Chloride

Abstract

This study outlines the use of 1,2-indanedione/zinc chloride (IND/ZnCl2) to treat fingermarks with a view to observing possible trends that may be present in a donor population. Fingermark samples from 131 donors were treated and subsequently evaluated using the grading scale devised by the Home Office Police Scientific Development Branch (now the Centre for Applied Science and Technology; CAST), UK. Out of a total of 1310 grades assigned, only 6 (0.5 %) returned a score of 0 and 64.6 % of all grades assigned were a 3 or 4. These tests indicated that grades for fingermarks developed within 3 days vary significantly depending on the age of the donor and the washing of hands prior to deposition. Donors who did not wash their hands the hour prior to deposition, or were below the age of 25, were more likely to offer higher grades. With fresh fingermarks, no significant variation in fingermark grades was observed that could be associated with food consumption, sex of the donor or recent use of cosmetics. The results for the treated 1 month old fingermarks agreed with the findings for fresh fingermarks, with the exception of washing of hands. In this case no significant difference was found between samples where donors had and had not washed their hands prior to deposition.