The 'triple contrast' method in experimental wound ballistics and backspatter analysis.

Schyma, Christian; Lux, Constantin; Madea, Burkhard; Courts, Cornelius (2015). The 'triple contrast' method in experimental wound ballistics and backspatter analysis. International journal of legal medicine, 129(5), pp. 1027-1033. Springer 10.1007/s00414-015-1151-0

[img] Text
art%3A10.1007%2Fs00414-015-1151-0.pdf - Published Version
Restricted to registered users only
Available under License Publisher holds Copyright.

Download (2MB) | Request a copy

In practical forensic casework, backspatter recovered from shooters' hands can be an indicator of self-inflicted gunshot wounds to the head. In such cases, backspatter retrieved from inside the barrel indicates that the weapon found at the death scene was involved in causing the injury to the head. However, systematic research on the aspects conditioning presence, amount and specific patterns of backspatter is lacking so far. Herein, a new concept of backspatter investigation is presented, comprising staining technique, weapon and target medium: the 'triple contrast method' was developed, tested and is introduced for experimental backspatter analysis. First, mixtures of various proportions of acrylic paint for optical detection, barium sulphate for radiocontrast imaging in computed tomography and fresh human blood for PCR-based DNA profiling were generated (triple mixture) and tested for DNA quantification and short tandem repeat (STR) typing success. All tested mixtures yielded sufficient DNA that produced full STR profiles suitable for forensic identification. Then, for backspatter analysis, sealed foil bags containing the triple mixture were attached to plastic bottles filled with 10 % ballistic gelatine and covered by a 2-3-mm layer of silicone. To simulate backspatter, close contact shots were fired at these models. Endoscopy of the barrel inside revealed coloured backspatter containing typable DNA and radiographic imaging showed a contrasted bullet path in the gelatine. Cross sections of the gelatine core exhibited cracks and fissures stained by the acrylic paint facilitating wound ballistic analysis.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Service Sector > Institute of Legal Medicine
04 Faculty of Medicine > Service Sector > Institute of Legal Medicine > Forensic Medicine

UniBE Contributor:

Schyma, Christian

ISSN:

0937-9827

Publisher:

Springer

Language:

English

Submitter:

Antoinette Angehrn

Date Deposited:

06 Feb 2015 13:58

Last Modified:

26 Jun 2016 01:58

Publisher DOI:

10.1007/s00414-015-1151-0

PubMed ID:

25616629

BORIS DOI:

10.7892/boris.62627

URI:

https://boris.unibe.ch/id/eprint/62627

Actions (login required)

Edit item Edit item
Provide Feedback