Assessing the Quality of 3-Dimensional Imaging on the BrassTrax HD3D System and Validating an In-Silico Solution to Confirm NIBIN Hits

As submitted by the proposer: The National Integrated Ballistic Information Network (NIBIN) is a national network of linked Integrated Ballistic Identification Systems (IBIS). Through the use of state of the art photography, IBIS digitally captures the unique marks on cartridge cases left at crime scenes or test-fired through firearms. The use of NIBIN/IBIS provides the means by which firearms examiners can discover links between previously unrelated gun crimes. Such links provide valuable and actionable intelligence through which local law enforcement can identify and target active shooters. However, this intelligence must be provided in a timely manner or its usefulness is significantly diminished. Currently, any NIBIN associations, or hits, must be confirmed by comparing cartridge cases on a comparison microscope. For many NIBIN sites this leads to delays associated with the resubmission of evidence for that comparison. Our study proposes to examine the possibility of utilizing three-dimensional (3D) imagery for the limited purposes of confirming matches detected through the use of NIBIN/IBIS. The latest IBIS technology, BrassTrax HD3D, will be utilized to image and compare cartridge cases. The current method of comparison microscopy will also be utilized. Comparing the ability of the BrassTrax HD3D to the current gold standard, comparison microscopy, will be used to address the following research goals: 1. Study the ability of examiners to accurately identify matching cartridge cases using 3D imaging technology. The benefits and limitations of using 3-dimensional images captured by BrassTrax HD3D to confirm associations between fired cartridge cases in-silico will be studied and discussed. 2. Derive descriptive statistics for the difference in performance between the BrassTrax HD3D system and the comparison microscope to determine differences in sensitivity, specificity and both false positive and false negative rates. Use these data to establish validation thresholds to guide the development of interpretation guidelines and inform the forensic community of findings. This project contains a research and/or development component, as defined in applicable law. ca/ncf