| Summary: | It is a statement widely agreed upon that the friction ridge detail on a finger is unique to each digit and to find two that are exactly alike, between any two humans, is highly improbable. For this reason, fingermarks are considered of great importance to the judicial system as a match between two marks can confirm a shared identity. Due to the potential for identification, attempts to improve development processes of fingermarks is an area of interest for many researchers. One area that has been scarcely investigated is the development of latent fingermarks on ammunition by using time of flight secondary ion mass spectrometry.
This study aimed to adapt processes that have been used in other research to generate a complete image of a fingermark on the surface of a round. The fulfilment of this aim was facilitated by conversations with East Midlands Special Operations Unit (EMSOU) and their desire to develop images of fingermarks on evidence in the form of unfired 12mm Mark Webley rounds. With the success of this study, the evidence from this cold case can now be examined. Furthermore, where other techniques might fail, ToF SIMS has been shown as a technique that can be used to yield a clear fingermark.
Full scans of the round from ToF SIMS yielded high-quality images with several examples of minutiae clearly visible over the fingermark. These images were compared with those generated through ink or conventional fuming and staining techniques. In each case, the ToF SIMS image was superior, showing a greater level of detail.
The main sample, a 12 mm Mark Webley round, of this experiment was analysed on three separate occasions. The first occasion was one day after the mark was left on the surface, the second, seven days, and the third, seven months. ToF SIMS recorded no loss of detail over the time course of this experiment with all three images from each analysis period looking virtually identical.
|
|---|