Evaluation of Total Nitrite Pattern Visualization as an Improved Method for Gunshot Residue Detection and its Application to Casework Samples

• Berger, Jason ^[1] ; Upton, Colin ^[1] ; Springer, Elyah ^[1]
  1. [1] Police Laboratory, New York City Police Department
• Localización: Journal of forensic sciences, ISSN-e 1556-4029, ISSN 0022-1198, Vol. 64, Nº. 1, 2019, págs. 218-222
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen

  • Visualization of nitrite residues is essential in gunshot distance determination. Current protocols for the detection of nitrites include, among other tests, the Modified Griess Test (MGT). This method is limited as nitrite residues are unstable in the environment and lim- ited to partially burned gunpowder. Previous research demonstrated the ability of alkaline hydrolysis to convert nitrates to nitrites, allowing visualization of unburned gunpowder particles using the MGT. This is referred to as Total Nitrite Pattern Visualization (TNV). TNV techniques were modified and a study conducted to streamline the procedure outlined in the literature to maximize the efficacy of the TNV in casework, while reducing the required time from 1 h to 5 min, and enhancing effectiveness on blood-soiled samples. The TNV method was found to provide significant improvement in the ability to detect significant nitrite residues, without sacrificing efficiency, that would allow for the determi-nation of the muzzle-to-target distance.