AbstractDirect comparison of dermal and epidermal fingerprints can be vital to the identification of bodies where the epidermal skin layer is no longer available for fingerprinting. It has been reported that identification based on the comparison between dermal and epidermal fingerprints is possible, however, there is limited research that supports this supposition. Epidermal desquamation occurs during the fixation of a body in Thiel embalming fluid providing an opportunity to compare dermal and epidermal fingerprints from one individual.
This study aimed to determine at which histological skin sublayer epidermal desquamation occurs in Thiel-embalmed bodies, to collect and compare dermal and epidermal fingerprints to understand which recovery method is optimal, to determine the accuracy with which these can be compared.
Tissue samples were collected from 40 individuals and fingerprints were collected from 67 individuals using black powder and photography pre and post embalming. Analysis of the tissue samples ensured that the prints recovered after embalming were dermal prints. Quality and minutiae analysis were performed by the author and by experienced fingerprint examiners (n = 16) from four countries on 80 fingerprint pairs (powder fingerprint pairs n = 40, photography fingerprint pairs n = 40).
There was a higher percentage of usable epidermal fingerprints recovered using black powder (91%) than using photography (72%). However, there was a lower percentage of usable dermal fingerprints recovered using black powder (64%) than using photography (81%). The results of the fingerprint comparison showed that fingerprint examiners were able to match a pair of fingerprints (identification) accurately in 10 to 15% of cases and they were able to establish fingerprint pairs as non-matching in 30 to 45% of cases.
Thiel-embalmed bodies offer a valid opportunity to study epidermal and dermal fingerprints collected from the same source. The collection, analysis, and comparison of epidermal and dermal fingerprint pairs should be approached by fingerprint examiners with caution, especially in cases where the fingerprints are collected from elderly individuals.
|Date of Award||2021|
|Sponsors||Engineering and Physical Sciences Research Council|
|Supervisor||Lucina Hackman (Supervisor) & Helen Langstaff (Supervisor)|
- dermal fingerprints
- Theil embalming