Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Firearms & Toolmarks Subcommittee

OSAC Firearms & Toolmarks SC icon

The Firearms & Toolmarks Subcommittee focuses on standards and guidelines related to the examination of firearm and toolmark evidence. This includes the comparison of microscopic toolmarks on bullets, cartridge cases, and other ammunition components and may also include firearm function testing, serial number restoration, muzzle-to-object distance determination, tools, and toolmarks.

Officers | Members | Standards | Other Work Products 



Todd Weller, Subcommittee Chair, Weller Forensics, LLC

Erica Lawton, Subcommittee Vice Chair, Alabama Department of Forensic Sciences; University of South Alabama

Justine Kreso, Subcommittee Executive Secretary, Onondaga County Center for Forensic Sciences


Carey M. Alvarez Bacha, Unified Metropolitan Forensic Crime Laboratory

Michael Beddow, Phoenix Police Department Crime Laboratory

Zachary Carr, Johnson County Sheriff's Office Criminalistics Laboratory

James Carroll, Los Angeles County Sheriff's Department Crime Laboratory

Theodore Chavez, Federal Bureau of Investigation

Eric CollinsBureau of Alcohol, Tobacco, Firearms & Explosives

Kyle Felix, United States Army Criminal Investigation Laboratory

Stefanie Happ, El Paso County Sheriff's Office

Stacey Hartman, Indiana State Police

Ryan Lilien, Cadre Research Labs

Stephanie Madon, Arizona State University (Human Factors Task Group representative)

Max Morris, Iowa State University (Statistics Task Group representative)

Rebecca Mullen, Arkansas State Crime Laboratory (Quality Task Group representative)

Kevin Rippman, Bureau of Alcohol, Firearms, Tobacco and Explosives


Maneka Sinha, University of Maryland, School of Law (Legal Task Group representative)

Johannes Soons, National Institute of Standards and Technology

Michael Stocker, National Institute of Standards and Technology

Raymond Valerio, Queens District Attorney's Office  (Legal Task Group representative)

Eric Warren, SEP Forensic Consultants

Alan Zheng, National Institute of Standards and Technology 

Firearms & Toolmarks Affiliate List


On the OSAC Registry

OSAC Registry Ribbon
  • ANSI/ASB Best Practice Recommendation 060, Guidelines for Barrel and Overall Length Measurements of Firearms. 2021. 1st. Ed. (added May 2, 2023).
  • ANSI/ASB Standard 061, Firearms and Toolmarks 3D Measurement Systems and Measurement Quality Control. 2021. 1st. Ed. (added March 1, 2022).
  • ANSI/ASB Standard 062, Standard for Topography Comparison Software for Toolmark Analysis. 2021. 1st. Ed. (added August 2, 2022).
  • ANSI/ASB Standard 063, Implementation of 3D Technologies in Forensic Firearm and Toolmark Comparison Laboratories. 2021. 1st. Ed. (added August 2, 2022).
  • ANSI/ASB Best Practice Recommendation 068, Safe Handling of Firearms and Ammunition. 2020. 1st. Ed. (added April 6, 2021).
  • ANSI/ASB Standard 093, Standard Test Method for the Examination and Testing of Firearms. 2020. 1st. Ed. (added November 2, 2021).
  • ANSI/ASB Standard 096, Standard Method for the Examination and Documentation of Ammunition and Ammunition Components. 2022. 1st. Ed. (added October 3, 2023). 
  • ANSI/ASB Best Practice Recommendation 107, Best Practice Recommendation for Measuring Trigger Pull of a Firearm and Estimating Its Uncertainty. 2022. 1st. Ed. (added September 5, 2023). 
  • OSAC 2021-N-0012, Standard for Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program (added October 4, 2022 and sent to ASB for further development and publication). 

Published by a Standards Developing Organization (SDO) & Eligible for the OSAC Registry

At an SDO for Further Development & Publication

Standards Under Development

  • Standard Test Method for the Examination and Restoration of Obliterated Serial Numbers.
  • Standard Test Method for Muzzle-to-Garment Distance Determinations.
  • Standard for 3D Virtual Comparison Microscopy for Firearm and Toolmark Analysis.
  • Best Practice Recommendation for Muzzle to Target Measurements and Measuring its Uncertainty.
  • Standard Test Method for the Examination and Comparison of Toolmarks for Source Attribution.
  • Supporting Documentation of Source Conclusions in Toolmark Examinations.
  • Guidelines for Reporting of Source Conclusions in Toolmark Examinations.
  • Standard for Documentation of Comparisons.
  • Best Practices for the Resolution of Conflicts in Toolmark Source Conclusions.
  • Technical Report on Reporting Results from 3D Measurement Systems and Algorithm-Assisted/Based Comparisons.

Other Work Products

Process Maps

Research & Development Needs

Reference Documents

Note: Subcommittee position statements or responses to data collections by the subcommittee do not necessarily represent the position of OSAC or NIST.

Webinars, Presentations & Training Videos

Discipline-Specific Bibliographies and Bibliographic References 

These documents may contain information to help forensic scientists, judges, lawyers, researchers, and other readers better understand the nature, scope, and foundations of the individual disciplines as currently practiced. The identification of these documents does not represent an endorsement by OSAC or NIST. Only standards that are posted on the OSAC Registry and Technical Guidance documents, are endorsed by OSAC. The referenced documents may be subject to copyright. Note: Subcommittee position statements or responses to data collections by the subcommittee do not necessarily represent the position of OSAC or NIST.

Created June 27, 2014, Updated March 5, 2024