Firearms and Toolmarks

Erica Lawton

AFTE 2021
Subcommittee Leadership

Position Name Organization Email

Chair Erica Lawton Alabama Dept. of Forensic 

Sciences

erica.Lawton@adfs.alabama.gov

Vice Chair Todd Weller Weller Forensics, LLC toddweller@wellerforensics.com

Executive 

Secretary

Melissa Oberg Indiana State Police moberg@isp.in.gov

In October 2020, Todd Weller stepped down as Chair and Erica Lawton was elected Chair
Subcommittee Voting Members

# Name Organization # Name Organization

1 Steve Scott FBI 12 Stephanie Happ El Paso County Sheriff’s Office

2 Mike Neel Bureau of Alcohol Tobacco Firearms and 

Explosives

13 Hans Soon NIST

3 Zachary Carr Johnson County Sheriff’s Office 14 Bill Demuth Illinois State Police

4 Ted Vorburger, PhD NIST 15 Melissa Oberg Indiana State Police Crime Lab

5 Eric Collins Contra Costa Co Sheriff Forensic Services 16 Erica Lawton Alabama Department of Forensic Science

6 Jason Crafton Missouri State Crime Lab 17 Nicholas Petraco John Jay College

7 Max Morris, PhD Iowa State University 18 Michael Stocker NIST

8 Rebecca Mullen Arkansas State Crime Lab 19 Todd Weller Weller Forensics

9 Erich Smith FBI 20 Carey Alvarez Bacha Unified Metropolitan Forensic Crime Lab

10 James Carroll Los Angeles County Sheriff’s Office 21 Stephanie Madon Iowa State University

11 Cassey Allen TX Department of Public Safety - Austin 22 Maneka Sinha University of Maryland Carey School of Law

Resource TG Representative

Stephanie Madon Human Factors

Max Morris Statistics

Rebecca Mullen QIC

Maneka Sinha Legal Resources
Subcommittee Affiliate Members

# Name Organization

1 Jodi Marsanopoli Bureau of Alcohol Tobacco Firearms and Explosives

2 John Murdock Contra Costa County Crime Laboratory

3 Nancy McCombs California Department of Justice, Fresno

4 Gerhard Wevers Institute of Environmental Science and Research, New Zealand

5 Chris Monturo Hamilton County Coroner’s Office

6 Wendy Gibson VA Department of Forensic Science

7 Laura Knowles Royal Canadian Mounted Police

8 Bridget Chambers Metro Nashville Police Department

9 Gerard Dutton Tasmania Police, Australia

10 Ryan Lilien Cadre Research

11 Alan Zheng NIST

12 Theo Chavez Federal Bureau of Investigation

13 Stacey Hartman Indiana State Police
Employer Classification Mix of 

Voting Members

26%

14%

23%

6%

31%

Employer Classification

Employer Classification

State Government

Federal Government

Local Government

Private Forensic Pracitioner

Academic/Researcher
OSAC Firearms & Toolmarks Website

• Google “OSAC Firearms”

• Top Hit

https://www.nist.gov/topics/forensic-science/organization-scientific-areacommittees-osac/firearms-and-toolmarks

• SWGGUN legacy documents, research needs, etc.
OSAC Firearms & Toolmarks Website
8

Notify committee 

chair ahead of time

Non-STRP 

route

New OSAC 2.0 Process
Overview FATM Subcommittee

Firearm Examination TG

Day to day laboratory 

examinations

Novel Technology TG

Standards for emerging technology; 

e.g. 3D imaging and comparison 

algorithms 

Uncertainty of Measurement TG

Measurement uncertainty and 

quantifying decisions

Training TG

Standards new examiners 

and training program

Executive Committee

Manage task groups (TG) and performs 

administrative tasks of subcommittee

Criteria for Identification TG

Standards regarding 

comparison conclusions

Winter 2015: FATM subcommittee formed task groups to focus on 

the most pressing/important topic areas in the discipline. The same 

task groups still exist and continue to work on standards and 

guidelines in each topic area.
Firearm & Toolmark Examination Task Group

Document Title Status

Standard Guideline/Best Practice for the Safe Handling of 

Firearms and Ammunition 

OSAC Registry April 6, 2021 

Standard Test Method for the Examination and Testing of 

Firearms

ASB STD 093

Going for FSSB Vote

Standard Test Method for the Examination and Testing of Fired 

Ammunition Components

Sent to SDO

Standard Method for the Examination and Documentation of 

Non-Firearm Tools and Toolmarks

Sent to SDO

Standard Test Method for the Examination and Restoration of 

Obliterated Serial Numbers

2.0 Process: Moving to STRP 

step

Standard Test Method for Muzzle-to-Garment Distance 

Determination

Draft in progress

Standard Test Method for the Examination and Comparison of

Toolmarks for Source Attribution

Draft in progress
Novel Technology Task Group

Document Title Document Status

Standard for Topography Comparison Software

for Firearm and Toolmark Analysis

Passed ASB, going to ANSI

Standard for Implementation of 3D Technologies in Forensic 

Laboratories for Firearm and Toolmark Analysis

Passed ASB, going to ANSI

Standard for 3D Measurement Systems and Measurement 

Quality Control for Firearm and Toolmark Analysis

Passed ASB, going to ANSI

3D Virtual Comparison Microscopy Draft in Progress

Technical Report of Reporting Results from 3D 

Measurement Systems and Algorithm-assisted/based 

Comparisons

Draft in Process
Uncertainty of Measurement Task Group

Document Title Status

Best Practice Recommendation for Barrel and Overall Length 

Measurement for Firearms

Sent to ASB

Best Practice Recommendation for Measuring Trigger Pull of a 

Firearm and Estimating its Uncertainty

Sent to ASB

Best Practice Recommendation for Muzzle to Target 

Measurements and Measuring its Uncertainty

Draft in progress
Training Task Group Progress

Document Title Status

Minimum Qualifications of Firearm/Toolmark 

Examiners Trainees

Sent to ASB

Standard for Firearm and Toolmark Examination 

Training Program

2.0 Process: Open Comment

Period Closed, Finalizing 

Comment Adjudication 

before FSSB vote, Then send 

to ASB
Source Conclusions Task Group Progress

Planned Actions Status

Range of Source Conclusions and Criteria in 

Toolmark Examinations

Sent to ASB

Standard for Peer Review of Source Conclusions in 

Toolmark Examinations

Sent to ASB

Expression of Source Conclusions Draft in progress

Best Practices for the Resolution of Conflicts in 

Toolmark Source Conclusions

Draft in progress
Process Map Task Group

• Formed new task group in conjunction with AFTE 

leadership & NIST guidance to develop a Process Map 

for firearm & toolmark examination

• UPDATE: January 19, 2021 Published on OSAC website

Process Map Task Group Members:

Gerard Dutton, Zachary Carr, Stephanie Happ, Stacey Hartman, Bridget Chambers, 

William (Bill) Demuth, and Ron Nichols

OSAC Office Facilitators:

Melissa Taylor, Heather Waltke, and Blythe Toma
Firearms Process Map
Firearms Process Map
Research Needs

• Each year we are asked to evaluate research needs within our 

discipline, the six current needs published include:

• Assessment of Examiners’ Toolmark Categorization Accuracy

• Blind Verifications Needs Assessment

• Cognitive Bias: To What Extent Does It Affect Firearm and Toolmark

Comparison Outcomes

• Consistency of Examiner Evaluation of Distance Determination GSR 

Patterns

• Evaluation of Examiner Conclusions Utilizing a Five-Point Scale

• Study to Assess the Accuracy and Reliability of Firearm and Toolmark

Examinations

• More details available on website
Sub-committee Needs

• Members:

• Term limits: each year old members term out and new 

members are needed each October

• https://www.nist.gov/osac-application-form

•STRP Volunteers

• Review of documents prior to 30 day open comment 

period and addition to the OSAC 2.0 Registry

• https://www.nist.gov/osac-application-form
Questions?

• Email:

• lawton5007@gmail.com

• erica.Lawton@adfs.alabama.gov