NCJ Number
197381
Journal
Law Enforcement Technology Volume: 29 Issue: 10 Dated: October 2002 Pages: 180,182,185
Date Published
October 2002
Length
5 pages
Annotation
This article describes the new National Institute of Standards and Technology (NIST) bullet and casing standard.
Abstract
This new standard augments the developing technology of computer--automated firearms identification currently being used by firearm examiners. Ballistic evidence is considered valuable because each gun’s firing pin and ejection mechanism imparts distinctive markings--known as signatures on fired bullets and ejected casings. Computer-aided ballistic systems were developed expressly to automate signature identification. They also reduce the workload of firearms examiners, and keep forensic laboratories from being overwhelmed by crime rates, budgetary reductions, and lack of qualified personnel. The Integrated Ballistic Identification System (IBIS) takes digital microscopic images of identifying features found on expended bullets and cartridge casings found at crime scenes. It compares them with similarly acquired images from test-fired guns involved in other crimes that are stored in computer databases. The system presents examiners with a list of likely candidates, which can then be viewed on high-resolution monitors for comparison. In laboratories using this technology, calibration is being achieved by acquiring a set of laboratory test-fired bullets and casings to be used as benchmarks. Benchmarks are routinely compared on the system to monitor calibration, image quality, image acquisition proficiency, hardware and software performance and stability, and performance assessment after maintenance or technology upgrades. The NIST standard closes a calibration loophole exposed when police crime lab computers are networked together. Networking is the next step in the evolving technology of computer-aided firearms identification. The NIST standards may also be used as a training tool for the new IBIS user and to measure the consistency and accuracy of the user at a later date.