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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 



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

Todd Weller, Subcommittee Vice Chair, Weller Forensics, LLC

Melissa Oberg, Subcommittee Executive Secretary, Indiana State Police


Carey M. Alvarez Bacha, Unified Metropolitan Forensic Crime Laboratory

Zachary Carr, Johnson County Sheriff's Office Criminalistics Laboratory

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

Theodore Chavez, Federal Bureau of Investigation

Jason Crafton, Missouri State Highway Patrol Crime Laboratory

Stefanie Happ, El Paso County Sheriff's Office

Stacey Hartman, Indiana State Police

Ryan Lilien, Cadre

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

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

Nicholas Petraco, City University of New York

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

James (Steve) Scott, Federal Bureau of Investigation - TEDAC Laboratory

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

Ted Vorburger, National Institute of Standards and Technology/Stratevia

Eric Warren, SEP Forensic Consultants

Alan Zheng, National Institute of Standards and Technology


SDO Published Standards

Standards at an SDO

Standards Under Development

  • OSAC 2021-N-0012, Standard for Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program.
  • Supporting Documentation of Source Conclusions in Toolmark Examinations.
  • Guidelines for Reporting of Source Conclusions in Toolmark Examinations. 
  • Standard for 3D Virtual Comparison Microscopy for Firearm and Toolmark Analysis.
  • Best Practice Recommendation for Creating Known Distance Witness Panel and Estimating the Associated Measurement of Uncertainty. 
  • Standard Test Method for the Examination and Restoration of Obliterated Serial Numbers.
  • Standard Test Method for the Examination and Comparison of Toolmarks for Source Attribution.
  • Best Practice Recommendation for Muzzle to Target Measurements and Measuring Uncertainty.

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 1, 2022