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Firearms & Toolmarks Subcommittee

Members of the OSAC Firearms and Toolmarks Subcommittee
Members of the Firearms & Toolmarks Subcommittee at the July 2019 OSAC Meeting in Orlando, Florida.

Officers | Members | Standards | Discipline-Specific Baseline Documents | Research & Development Needs | Presentations

The Firearms and 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.


Todd Weller, Subcommittee Chair, Weller Forensics, LLC

Erica Lawton, Subcommittee Vice Chair, Alabama Department of Forensic Sciences

Wendy Gibson,  Executive Secretary, Virginia Department of Forensic Science


Cassey Allen, Texas Department of Public Safety 

Carey M. Alvarez Bacha, Unified Metropolitan Forensic Crime Laboratory

Zachary Carr, Johnson County Sheriff's Office Criminalistics Laboratory

Eric Collins, Contra Costa County (California) Office of the Sheriff, Forensic Services Division

Jason Crafton, Missouri State Highway Patrol Crime Laboratory

William Demuth, II, Illinois State Police, Division of Forensic Services

Stefanie Happ, El Paso County Sheriff's Office

Ryan Lilien, M.D./Ph.D., Cadre Research Labs

Stephanie Madon, Iowa State University (Human Factors Representative)

Max Morris, Ph.D., Iowa State University

Rebecca Mullen, Arkansas State Crime Laboratory (Quality Representative)

Douglas Murphy, Terrorist Explosive Device Analytical Center, Federal Bureau of Investigation

Michael Neel, Bureau of Alcohol, Tobacco, Firearms and Explosives

Melissa Oberg, Indiana State Police

Nicholas Petraco, John Jay College of Criminal Justice

Maneka Sinha, University of Maryland Carey School of Law (Legal Representative)

Erich Smith, Federal Bureau of Investigation

Johannes A. Soons, National Institute of Standards and Technology

Xiaoyu Alan Zheng, National Institute of Standards and Technology


Tier 1: On the OSAC Registry

  • None currently.

Tier 2: Published by an SDO

  • None currently.

Tier 3: Sent to an SDO

Tier 4: Under Development

  • Standard for 3D Virtual Comparison Microscopy for Firearm and Toolmark Analysis.
  • Requirements and Recommendations for a Firearm and Toolmark Examiner Training Program.
  • Standard Method for the Examination and Documentation of Tools and Toolmarks.
  • Standard Test Method for the Examination and Restoration of Obliterated Serial Numbers.

Discipline-Specific Baseline Documents

The Forensic Science Standards Board (FSSB) has provided the opportunity for OSAC Subcommittees to identify baseline documents and reference materials that best reflect the current state of the practice within their respective disciplines. 

These documents contain practical information regarding these disciplines that can help forensic scientists, judges, lawyers, researchers, other interested parties and the general public, to better understand the nature, scope, and foundations of the individual disciplines as they are currently practiced.

It is important to note that the identification of these documents in this venue does not represent an endorsement by OSAC or NIST.  Only documents that are posted on the OSAC Registries constitute OSAC endorsement. All copyrights for these documents are reserved by their owners. Subcommittee position statements or responses to data collections by the subcommittee represent the consensus opinion of the subcommittee, not necessarily the position of the entire OSAC organization or NIST.

Research & Development Needs


In general, the development of standards and guidelines is transitioning from the Scientific Working Groups (SWGs) to the OSAC. Some SWGs will continue to operate to provide other resources within their discipline. The existing SWG documents will remain in effect until updated documents are disseminated by the OSAC or the SWG. SWGDAM will retain the responsibility for updating the FBI DNA Quality Assurance Standards.

– Forensic Science Standards Board: March 2015

Created June 27, 2014, Updated August 6, 2020