French James, Morgan Ruth
Department of Security and Crime Science, University College London, 35 Tavistock Square, London WC1H 9EZ, United Kingdom; JDI Centre for the Forensic Sciences, University College London, 35 Tavistock Square, London WC1H 9EZ, United Kingdom.
JDI Centre for the Forensic Sciences, University College London, 35 Tavistock Square, London WC1H 9EZ, United Kingdom.
Forensic Sci Int. 2015 Feb;247:14-7. doi: 10.1016/j.forsciint.2014.10.023. Epub 2014 Oct 24.
Experiments were undertaken in order to explore the potential for gunshot residue (GSR) particles to undergo tertiary transfer, and to be deposited on individuals in the vicinity of a firearm discharge. Samples were taken from hands following a series of test-firings. SEM-EDX with automated detection and analysis software was used to determine the presence of GSR on these samples. As many as 22 particles were found to have undergone tertiary transfer via a series of handshakes following a firearm discharge. In one run, a particle measuring 49.19 μm was recovered from a tertiary transfer recipient. Significant numbers of particles were also recovered from bystanders, with as many as 36 being detected on a sample taken from an individual who was in the proximity of a firearm discharge. The implications of these observations for forensic investigations are considered. In particular, the need to prevent unwanted transfer during the collection phase is highlighted, and the importance of acknowledging the possibility of secondary and tertiary transfers when reconstructing firearms incidents is also stressed. Experimental studies offer a means of improving our understanding of the dynamics of GSR transfer and deposition, and assisting the forensic reconstruction of firearms incidents.
开展了实验，以探究枪击残留物（GSR）颗粒发生三级转移并沉积在枪支发射附近人员身上的可能性。在一系列试射后从手上采集样本。使用配备自动检测和分析软件的扫描电子显微镜-能谱仪（SEM-EDX）来确定这些样本上是否存在GSR。发现多达22个颗粒在枪支发射后通过一系列握手发生了三级转移。在一次试验中，从一名三级转移接受者身上回收了一个尺寸为49.19μm的颗粒。还从旁观者身上回收了大量颗粒，在从一名处于枪支发射附近的人员身上采集的样本中检测到多达36个颗粒。考虑了这些观察结果对法医调查的影响。特别强调了在采集阶段防止不必要转移的必要性，同时也强调了在重建枪支事件时认识到二级和三级转移可能性的重要性。实验研究提供了一种手段，有助于我们更好地理解GSR转移和沉积的动态过程，并协助对枪支事件进行法医重建。
