Examination of Firearms Review: 2007 to 2010 - Interpol

internationally attended event, with representatives from 17 countries and
approximately 350 attendees (40). The conference was important to the forensic
science community because the last symposium of its kind focusing on trace
evidence was in San Antonio, Texas (USA), in 1997. In the glass field, several
papers were presented emphasizing the value of elemental analysis (41);
specifically LA-ICP-MS (42, 43). Additionally, many workshops were given,
offering training and fostering discussion. In particular, the workshop entitled
Advanced Elemental Analysis of Trace Evidence Examinations, dealt with topics
in forensic glass analysis. This event was so successful and well-received that it
is slated to be held biannually.
The second Trace Evidence Symposium was held in 2009 (44). Where the 2007
symposium agenda was fairly generalized, the 2009 Trace Evidence Symposium
offered more workshops and specialized topics, supplying analysts with further
training opportunities. Workshops on glass included The Use of Multivariate
Statistics in Trace Evidence Investigations, Advanced Elemental Analysis,
Physical Match Theory, Standardized Test Methods and Insuring Quality in the
Trace Laboratory, and Report Writing. This offered yet another opportunity to
focus on responding to the NAS report, both refuting some of the findings and
challenging forensic scientists to improve.
2.2.7 SWGMAT
The SWGMAT met in conjunction with the 2007 Trace Evidence Symposium and
separately in Fredericksburg, Virginia (USA) in 2008 and 2010. The SWGMAT is
very much focused on producing best practice guidelines for trace evidence
analysts. Once again, interpretation, standardization and reporting were heavily
debated. Some case studies were presented.
A presentation by Eyring (45) showed the use of a microspectrophotometer for
the objective determination of the color of glass fragments. The size required for
optimal analysis is larger than most recovered glass samples. Therefore, use of
this technique is not likely to be widespread.
As mentioned previously, the SWGMAT published the “Expert Reporting
Guideline” governing how glass analysts should write reports (46). Additionally, it
was reported (47) that the Glass Sub-Group of the SWGMAT is drafting guidance
for interpretation of results, and meeting admissibility requirements in courts.
The 2010 SWGMAT meeting concentrated primarily on building and defining
significance scales for trace evidence interpretation, but no guidelines on the
subject have been issued to date. A new Interpretation Sub-Group was formed
that will strive for some consistency across disciplines.
A transfer and persistence study by Green and Sheedy (48) found that the
uppers of the shoes have the greatest potential for particle recovery as they
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