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The Organization of Scientific Area Committees for Forensic Science

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 

 

Officers

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

Members

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

Bridget Chambers, Hamilton County Coroner & Crime Laboratory

Eric Collins, Bureau 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

Carissa Laughton, West Virginia State Police Forensic Laboratory

Ryan Lilien, Cadre Research Labs

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

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

Aimee Qulia, Federal Bureau of Investigation

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

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

Eric Warren, SEP Forensic Consultants

Alan Zheng, National Institute of Standards and Technology (NIST)

Firearms & Toolmarks Affiliate List

Proposed Standards by OSAC that are at an SDO for Further Development & Publication

All proposed standards listed below are completed work products of the OSAC Firearms & Toolmarks Subcommittee and have passed a rigorous technical and quality review by the subcommittee. The subcommittee encourages the forensic science community to implement these proposed standards. These proposed standards were developed by the Subcommittee, prior to October 1, 2020, when the OSAC Proposed Standards for the OSAC Registry approval procedures went into effect.

  1. Range of Source Conclusions and Criteria in Toolmark Examinations.
  2. Standard for Verification of Source Conclusions in Toolmark Examinations.

Standards

On the OSAC Registry

  • ANSI/ASB Best Practice Recommendation 060 Guidelines for Barrel and Overall Length Measurements of Firearms, 2021, 1st Ed. (added May 2, 2023)
  • ANSI/ASB Best Practice Recommendation 068 Safe Handling of Firearms and Ammunition, 2020, 1st Ed. (added April 6, 2021)
  • 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)
  • 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 Standard 093 Standard Test Method for the Forensic 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 Standard 162 Standard Method for the Forensic Examination and Documentation of Non-Firearm Tools and Toolmarks, 2024, 1st Ed. (added July 2, 2024)
  • OSAC 2021-N-0012 Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program (added October 4, 2022)
  • OSAC 2023-S-0018 Standard Test Method for the Restoration of Obliterated Serial Numbers and Other Markings (added December 3, 2024)
  • OSAC 2023-S-0028 Best Practice Recommendations for the Resolution of Conflicts in Toolmark Value Determinations and Source Conclusions (added January 13, 2025)
  • OSAC 2024-N-0010 Requirements and Recommendations for Competency Testing in Forensic Firearm and Toolmark Laboratories (added December 3, 2024)
  • OSAC 2024-S-0002 Standard Test Method for the Examination and Comparison of Toolmarks for Source Attribution (added January 13, 2025)

Published by a Standards Developing Organization (SDO); [Evaluated but Not Accepted for Registry]

At an SDO for Further Development & Publication

  • ASB Best Practice Recommendation 103 Guidelines for Reporting of Source Conclusions in Toolmark Examinations
  • ASB Best Practice Recommendation 161 Best Practice Recommendation for Creating Known Distance Witness Panels and Estimating the Associated Measurement Uncertainty
  • ASB Best Practice Recommendation 230 Best Practice Recommendation for the Resolution of Conflicts in Toolmark Value Determinations and Source Conclusions
  • ASB Standard 100 Standard Scale and Criteria for Source Conclusions in Toolmark Examinations
  • ASB Standard 101 Supporting Documentation of Source Conclusions in Toolmark Examinations
  • ASB Standard 102 Standard for Verification of Source Conclusions in Toolmark Examinations
  • ASB Standard 104 Standard for 3D Virtual Comparison Microscopy for Firearm and Toolmark Analysis
  • ASB Standard 105 Minimum Education Requirements for Firearm and Toolmark Examiner Trainees, 2nd Ed.
  • ASB Standard 124 Minimum Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program
  • ASB Standard 163 Standard Test Method for the Restoration of Obliterated Serial Numbers and Other Markings on Metal
  • ASB Standard 164 Standard Test Method for Muzzle to Target Distance Determinations
  • ASB Standard 228 Requirements and Recommendations for Competency Testing in Forensic Firearm and Toolmark Laboratories
  • ASB Standard 229 Standard for the Examination and Comparison of Toolmarks for Source Attribution
  • OSAC 2021-N-0012 Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program (OSAC Proposed Standard on the Registry)
  • OSAC 2023-S-0018 Standard Test Method for the Restoration of Obliterated Serial Numbers and Other Markings (OSAC Proposed Standard on the Registry)
  • OSAC 2023-S-0028 Best Practice Recommendations for the Resolution of Conflicts in Toolmark Value Determinations and Source Conclusions (OSAC Proposed Standard on the Registry)
  • OSAC 2024-N-0010 Requirements and Recommendations for Competency Testing in Forensic Firearm and Toolmark Laboratories (OSAC Proposed Standard on the Registry)
  • OSAC 2024-S-0002 Standard Test Method for the Examination and Comparison of Toolmarks for Source Attribution (OSAC Proposed Standard on the Registry)
  • Standard Scale of Source Conclusions and Criteria for Toolmark Examinations
  • Standard for Verification of Source Conclusions in Toolmark Examinations

Under Development

  • Expression of Source Conclusions
  • OSAC 2024-S-0014 Best Practice Recommendation for Muzzle-to Witness-Panel Distance Measurement and Estimation of Uncertainty
  • OSAC 2025-S-0005 Standard Test Method for Distance Determination (Gunshot Residue Distance and Shot Pellet Pattern Distance)
  • OSAC 2025-S-0020 Standard for the Review of Case Records in the Firearms and Toolmarks Discipline
  • Virtual Comparison Microscopy

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.