4.2. Interpretation
Alternative means of GSR deposition must be acknowledged when interpreting the presence of GSR on a surface or suspect. This is underlined by the results of this study, which demonstrate the possibility of tertiary transfers of GSR and depositions in the vicinity of a firearm discharge. When considering the probability that GSR recovered from a suspect was deposited as a result of firing a gun, alternative causes such as secondary and tertiary (indirect) transfer mechanisms, as well as radial deposition, should be considered. Indeed, the experimental data that have been presented may be referred to when estimating the probability that a particular mechanism was responsible for the deposition of GSR that has been recovered from a suspect. The results of the present study highlight the potential for misinterpretation if alternative transfer mechanisms are not acknowledged. The efficiency of the observed tertiary transfers suggests that further contacts (and extension of the transfer chains) would be effective in initiating further transfers of GSR. In terms of the size of particles involved in transfer, the results of the present study build on previous findings [8], indicating that transfers of GSR are not restricted to the involvement of small GSR particles. Rather, large particles (such as the particle measuring 49.19 mm recovered in run three of scenario one) may undergo successive transfers. Thus, caution is advised when attempting to draw inferences from GSR evidence and taking particle sizes into consideration.