Fingerprints from feathers
Dennis Gentles & Helen McMorris
The Royal Society for the Protection of Birds (RSPB) reports that since 1989, in Scotland alone, there have been over 500 birds of prey killed by illegal poisoning with a further 340 confirmed as shot, trapped or with their nests destroyed.
The surface onto which a fingermark has been deposited will ultimately determine the enhancement technique selected to develop that mark, in particular its porosity, however the condition and/or composition of the latent fingermark itself and the level of contamination present within the deposition, if any, are also contributing factors.
The microscopic weave structure of a feather has been likened to that of fine weave fabrics such as silk and nylon, upon which it is may be possible to develop grab marks using vacuum metal deposition and touch DNA profiling. The main aim of this study was to investigate a range of latent fingermark development techniques for the development of latent fingermarks on specific bird of prey feathers and eggs.
There are numerous enhancement techniques (physical and chemical) which have been developed for the successful visualisation of latent fingermarks. The ability to successfully develop latent fingermarks on the surface of bird of prey feathers and that of their eggs was investigated by trying many of the recognised fingermark development techniques as recommended by the Home Office Centre for Applied Science and Technology (CAST). Chemical development techniques such as Ninhydrin and DFO did not work at all with only limited success with Cyanoacrylate fuming.
Red and green magnetic fluorescent powders proved to be most successful on the surface of bird of prey flight feathers whereas black magnetic powder was the most successful technique on the eggs. These powders produced the highest quality of visible ridge-detailed developments over a controlled period of time.
Dennis Gentles works as lecturer in Crime Scene Investigation Techniques at Abertay University. He previously worked with Tayside Police as a police officer, spending most of his service as a scene of crime officer, becoming an authorised Forensic Scientist in 1990 and later a Crime Scene Manager.
In September 2003 he joined Abertay University to lecture on the newly formed BSc (Hons) Forensic Science programme and is still working in that role.
He specialises in fingerprints and has co-authored three published papers on that topic.
Helen McMorris is from County Fermanagh in Northern Ireland and was a student on the BSc (Hons) Forensic Science course at Abertay University. She graduated in 2012 with a First Class honours degree and started work as a fingermark examiner.
With a lifelong interest in wildlife, Helen’s honours project was ‘An investigation to develop suitable fingerprint enhancement techniques for use on the feathers and eggs of birds of prey that would be of significant use in wildlife crime.’ The project was devised by herself and supervised by Dennis Gentles. The project won awards from Forensic Science Society and FORREST and has since been published in Science and Justice.