Implementation of Digital Technologies to Improve Case Workflow and Documentation at a County Forensic Firearm Laboratory

This award to Dallas County’s (Texas) Southwestern Institute of Forensic Sciences will allow the laboratory to implement the emerging technology of automated three-dimensional (3D) physical scanning and virtual comparison microscopy into the firearms analysis workflow for the examination of firing pin impressions on cartridge cases. This new technology will supplement the laboratory’s current approach to the microscopic examination of toolmarks based upon direct two-dimensional (2D) light comparison microscopy. 3D scanning is an instrument-based metrological analysis that captures precise physical measurements of surface features such as toolmarks, including depth measurements that are not captured in standard 2D light microscopy. Using virtual comparison microscopy software, the resulting scan data files will be used to perform comparisons between known and exemplar toolmarks. This technology will enhance the firearm analysis process by generating complete, objective, and metrologically traceable measurement datasets for firing pin impressions that will then be the basis for downstream comparison processes. The technology will allow more complete casefile documentation of the firearm analysis process, and is expected improve efficiency by eliminating time-consuming setup and alignment steps that are required in direct 2D light comparison microscopy. Additionally, the project will fund the implementation of a digital image management system into the firearms analysis workflow, which will permit the organization, annotation, and retention of high-resolution digital photographs to document the examination of firearms evidence.