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Toolmark identification

Emerging Forensic Research Series: Firearms and Toolmarks Research

February 2019

Forensic science research and development plays a key role in the advancement of the practice of forensic science, as noted by the 2009 National Academies of Science report “Strengthening Forensic Sciences in the United States: A Path Forward.”

This webinar was presented by the NIJ Forensic Technology Center of Excellence on February 26, 2019.

Two-Pronged Study of Bullets Fired by Consecutively Rifled Barrels

December 2021

In this study, firearms examiners were asked to use traditional microscopic methods to identify unknown bullets to the appropriate barrels. Additionally, 3D scans of these bullets were used in a matching algorithm to find similarity scores between bullets. Error rates were determined and the potential for subclass carry-over among the barrels was evaluated. 

This webinar was presented by the NIJ Forensic Technology Center of Excellence on December 16, 2021.

Glock Pistol Toolmarks: A Literature Review and Introduction of Undocumented Toolmarks

December 2021

This webinar will expand examiners' awareness of additional areas of interest for identification purposes. Two previously undocumented toolmarks were observed in Glock pistols and could potentially be used for other make/model pistols. These new toolmarks will expand an examiner’s ability to compare fired and unfired ammunition components to each other or to a suspect firearm.

This webinar was presented by the NIJ Forensic Technology Center of Excellence on December 12, 2021.

Exploration of Breech Face Subclass Characteristics

December 2021

This study assesses the production of subclass characteristics during the manufacturing of breech faces. Observations on how well subclass characteristics persist on manufactured breech faces with and without any finishing methods as well as the effect of the primer on the quality/quantity of the breech face impressions will be discussed.    

This webinar was presented by the NIJ Forensic Technology Center of Excellence on December 9, 2021.

The Accuracy, Repeatability, and Reproducibility of Firearms/Toolmarks Comparisons

January 2022

This video is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. Video includes welcome remarks and a keynote address by Erich Smith, FBI Laboratory. The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. 

NIJ's Forensic Intelligence Initiative - Using Forensics for Crime Disruption and Prevention

January 2022

This video, a presentation by NIJ's Jonathan McGrath and Basia Lopez, is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. 

Crime Gun Intelligence Revolution: Day 3 Keynote at the Firearm & Toolmarks Policy & Practice Forum

January 2022

This video is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. This video includes welcoming remarks and the day keynote address by Thomas Chittum, Bureau of Alcohol, Tobacco, Firearms, and Explosives. The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. 

Impact of Advances in Computer Science, Statistics & Engineering on Firearms & Toolmarks Examination

January 2025

This video is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. This video includes a brief introduction and the keynote from day 2, which focused on emerging technologies. 

Support for Firearms and Toolmarks R&D at the National Institute of Justice

January 2022

This video, a presentation by Gregory Dutton, Ph.D., is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. 

Firearm and Toolmarks Policy and Practice Forum - Welcome and Keynote

January 2022

This video is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022.  Included are welcome message and keynote presentation "A Review of Scientific Foundations of Firearm Examination and Related Research," Theodore Vorburger, National Institute of Standards and Technology. The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. 

Scientific Foundation and the State of Firearms and Toolmark Research: Presentations & Expert Panel

January 2022

This video is one of 12 from the recorded at the Firearm and Toolmarks Policy and Practice Forum hosted by the NIJ Forensic Technology Center of Excellence January 11–14, 2022. Day 1 focused on Scientific Foundation and the State of Firearms and Toolmark Research. 

Presentations include:

Firearm and Toolmarks Policy and Practice Forum

The symposium included presentations and panel discussions on topics relevant to recent advances in firearm and toolmark examination with a focus on the future. The symposium brought together 685 criminal justice professionals to explore implementation of three-dimensional (3D) imaging technologies, best practices for forensic examination of firearm and toolmark evidence, federal initiatives, gun crime intelligence, black box studies on firearm and toolmark examination, legal challenges...

The Effect of Time on Rusted Firearm Identification

January 2022

Although iron-based metals are popular for making critical parts of firearms, they are susceptible to corrosion or rust. There is currently little research on how long a firearm can be left to rust before an identification is no longer possible. This project evaluates the effects of rust on the common working surfaces of Glock and Smith & Wesson Sigma firearms.