UCL Centre for the Forensic Sciences



The Persistence of Trace Evidence on Fabrics and its Forensic Implications

The need for empirical evidence bases: This research addresses a current debate within the literature concerning the importance and necessity of developing a body of empirical research which can inform each stage of the forensic process. Forensic questions should be answered using reference to data from published studies rather than primarily by reference to experience or craft knowledge. As such, it is paramount that research-based knowledge generated from empirical studies dictates forensic practices. Additionally, the establishment of empirical evidence bases is important for the admissibility of expert evidence in court.

Persistence of trace evidence: Trace evidence is often a valuable part of the forensic process offering both evidence and intelligence that can inform an investigation. Specifically, this project will focus on the persistence of different forms of trace evidence on fabrics, an area where there is a current gap in the available literature. To answer the research question put forth, a variety of different imaging techniques will be used in order to visualise the trace compounds over a given time scale, along with confirmatory analysis to validate what is being visualised. Using these techniques, the deposition and persistence of these traces on different fabrics will be studied. Additionally, environmental factors and their effect on persistence will be assessed. Finally, if time permits, the secondary transfer of trace evidence onto fabrics and its subsequent persistence will also be studied.

Presentation of trace evidence in the courtroom: Based on the results, the interpretation of trace evidence in relation to its persistence on different fabrics will be discussed with emphasis on the interpretation and presentation of expert evidence in court.