Gunshot Residue Test
This photo series demonstrates the use of the Instant Shooter Identification Kit (ISID-2) to detect the presence of gunshot residue on a shooter's hand. In the first photo, a "sticky-tab" carbon tape particle collection swab is used collect possible gunshot residue from various locations on an individual's hand. Once collected, the swabs are stored with a control swab until they can be analyzed by a scanning electron microscope (SEM) to confirm the presence of gunshot residue.
The second photo shows the results of a presumptive test on an individual who recently fired a handgun five times. The subjects hands (front and back, focusing on the web between the index finger and thumb) were swabbed with a special purpose patch. The patch was then exposed to a chemical reagent which indicates the presence of nitrocellulose in the form of blue spots and flecks. These flecks are highlighted by the red arrows.
The last photo is the same instant test conducted on an individual who had fired a heavy machine-gun numerous times. The blue reaction is present all over the patch indicating large quantities of nitrocellulose on the subject's hands.
According to the developer of the test, the presumptive Sandia LET instant shooter identification technique is 90% accurate. Results typically appear on the swab five minutes after exposure to the chemical reagent.