A report published in 2016 by the President's Council of Advisors on Science and Technology (PCAST) criticized studies that have been published regarding the discipline of firearm identification. This study was designed to answer some of these criticisms and involved 30 consecutively manufactured Beretta brand 9 mm Luger caliber barrels. This study had an "open set" design to help the discipline of firearm identification establish "Foundational Validity" which is outlined in the PCAST report. Seventy-two qualified firearm examiners completed and submitted answers for this study that included 15 knowns and 20 unknowns. There were an additional 5 firearms with similar characteristics as the Beretta barrels that were also included as unknowns which provided "known non-match" comparisons. Test sets were created using the random function in Microsoft Excel. Collaborative Testing Services (CTS) funded, facilitated, distributed the tests, and collected the answers from qualified firearm examiners throughout the United States and the world. Firearm examiners were able to complete the test of fired bullets with a low error rate. The error rate for the corrected data was 0.08% (1 in 1250) with the lower confidence interval as low as 0.01% (1 in 10,000) and the upper confidence interval being as high as 0.4% (1 in 250).
Keywords: Beretta; PCAST; barrels; comparison; consecutively manufactured; error rate; firearm identification; fired bullets; foundational validity; microscopic examination; validation study.
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