NCJ Number
82513
Date Published
1974
Length
70 pages
Annotation
The sodium rhodizonate test for lead as a method for the examination of gunshot residue patterns around bullet holes is evaluated and compared with other commonly used chemical and instrumental methods used in analyzing gunshot residues on target.
Abstract
One objective of the study was to establish the optimum conditions for the use of the rhodizonate reagents and then use the test to obtain information about the origin of the particulate debris in a typical gunshot residue pattern and the dynamic process by which this particulate material forms into a recognizable pattern on the surface of the target. The rhodizonate test was compared with other commonly used chemical and instrumental methods as to their sensitivity, specificity, and general utility in the evaluation of gunshot residues on targets. Also, although the analysis of residues on the hands is not within the scope of this study, some evaluation is made of techniques used for this purpose, since many of the same methods have been applied to both targets and hands. The sodium rhodizonate test was found to be an extremely sensitive, specific, and efficient method for the detection of gunshot residue around a bullet hole when the pattern can be developed directly on the target. The nitrite test and X-ray examination are both valuble methods for evaluation of residue patterns. Although neither is as sensitive as the rhodizonate test for the detection of residue from a lead bullet, both are at least as effective as sodium rhodizonate for the detection of residue left by the firing of a metal jacketed bullet. Tabular and graphic data are provided, along with 41 references.