OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE1 FirearmsProcess Map (Current Practice)

Introduction

The National Institute of Standards and Technology (NIST) facilitated the development of this Firearms Process Map through a collaboration between the NIST

Forensic Science Research Program and the NIST administered Organization of Scientific Area Committees (OSAC) for Forensic Sciences (specifically OSAC?s

Firearms and Toolmarks Subcommittee) in partnership with the Association of Firearm and Tool Mark Examiners (AFTE).

This Firearms Process Map (Current Practices) captures details about the various procedures, methods and decision points most frequently encountered in the

discipline of firearm examination from a national and international perspective and is intended to reflect current practices. The discipline of firearm examination

requires examiners to make many decisions that can impact the quality and accuracy of results. The Firearms Process Map can benefit the firearm examination

discipline by providing a behind-the-scenes perspective into the various components and decision points in the firearms analysis process.

Process mapping is the visual representation of critical steps and decision points of a process. Components of the process are deconstructed, placed into specific

shapes within a flowchart and connected by one-way arrows to indicate directionality regarding decisions as well as progression throughout the overall process.

The shape of each box assists the reader by representing a specific type of activity.

This process map captures the diverse practices of multiple laboratories, with the goal of allowing a firearm examiner to find their process represented in the

map. To ensure this, the mapping team avoided creating a map of what should be done (e.g., best practices) and instead attempted to represent all reasonable

variations of casework currently performed by firearm examiners. Forthis reason, it is important to state that neither the OSAC Firearms and Toolmarks

Subcommittee nor AFTE necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

This map is not intended to be a step-by-step instruction manual outlining minutia, nor is it intended to be so broad that it lacks utility. Rather, judgements were

made by the process mapping group as to which steps should be combined and which steps should be divided further. Certain processes represented in the map

have a required sequence while other components may vary by examiner or agency. Processes and decisions may also be dictated by agency policy or law.

Process Map Applications:

The Firearms Process Map is intended to be used to help improve efficiencies while reducing errors, highlight gaps where further research or standardization

would be beneficial, and assist with training new examiners. It may also be used to develop specific laboratory policies and identify best practices.

Scope of the Firearms Process Map:

The scope of this Firearms Process map is limited to core processes within the discipline of firearm and toolmark examination such as the examination of firearms

and the microscopic comparison of fired ammunition components. Several topics are omitted from this map to include individual characteristic databases,

toolmark examination, fracture matching and distance determination. These topics may subsequently be addressed by the process mapping team, an individual

laboratory or a standardization committee.
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE2 FirearmsProcess Map (Current Practice)

9000 - Other Examinations*

1000 - Administrative Assessment 2000 - Technical Assessment

5000 ?SubclassCharacteristics

3000 ? Unknown Analysis

6000 ? Individual CharacteristicDatabase (ICD)*

7000 ? Comparison/Evaluation 8000 ? Reportingand Verification

4000 ? Functionality / Operability /Known Analysis

Intake Criteria

Assessment

Inquiry Received Capacity

Assessment

Examiner

Evidence

Intake

Underlined Word

Word that will be defined

in the glossary

Known

Analysis/Suitability

Determination

TechnologyAssist

Technology that aidsin the steps on this page Input Box Outlinesthe inputsat

the beginningof each section

Output Box Describesan

output of the

steps on the

page

Discontinuation

of Assessment

or Examination

Feature

Assessment

Grouping

Based on Class

Characteristics

*Suitability

Determination

Report Projectile to

Projectile

(Pto P)

Cartridge Case

to Cartridge Case

(Cto C)

Cartridge Case

to Firearm

(Cto F)

Projectile to

Firearm

(Pto F)

Suitability

Determination

Verification

Technical/

Administrative Review

Test Fire

Barrel Length

Measurement

Trigger Pull

Measurement Functionality

Subclass Characteristics

Case

Assessment

Item Determination

Render Firearm

Safe

Ammunition to

Projectile/Cartridge Case/Ammunition

Serial Number Restoration

*Database

Entry

*Review of

Results

*Distance Determination*Toolmark

Examination

*Fracture Match*Miscellaneous

Examinations

*These processesarenot represented in thisdocument

*These processesarenot represented in thisdocument

Ammunition

Selection

Legend

Processstart/end

Process

Decision

Subprocess

Document
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE3 FirearmsProcess Map (Current Practice)

1100 - Intake CriteriaAssessment 1200 - Capacity Assessment

1110

Request Received

Return to Overview

1140

Doesit meet acceptance

criteria?

YES

1160

Discontinue

Evidence Receiving

and proceed PAP

1270

Create

Appropriate Case

Assignment(s)

1280

Werethere multiple

assignments for varying

disciplines?

1295

Process case PAP

1290

Transfer Case to

Assigned Examiner

NO

GOTO

2000

Examiner

Evidence

Intake

1120

Evaluate the request

for acceptance

criteria?

NO

1130

CaseAcceptance CriteriaPer Agency

Policy (PAP)

- Approval required?

- Approval received?

- Analysistimeframe appropriate?

- Description of evidence packaging

- Sufficient case related information

(i.e. police report)?

- Isthe request appropriate?

- Resource Evaluation: Time and

Expertise?

1150

Can the issue be

addressed

immediately?

NO

NO

YES

YES YES

Technology Assist

- LIMS

FROM 2160

1210

Initiate Evidence Receiving Process

Per Agency Policy (PAP)

- Unique Case Identifier

- Unique Item designation for

evidence

- Ensure firearm isunloaded

- Receipt generated and

provided to submittingagency

- Check/Ensure for proper

packaging/sealing

- Initiate Laboratory chain of

custody

- Generate appropriate

documentationPAP
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE4 FirearmsProcess Map (Current Practice)

2000 ? Examiner Evidence Intake

Return to Overview

2130

Inventory of Evidence

(mark package and

describe evidence Per

Agency Policy -PAP)

2140

All necessary

items

received?

2190

Review and Document

Pre-Examination Information

-Additional examination prior to

FATM examination

-Case Circumstances

2195

Output: Cataloged

evidence items

2160

Additional

evidence

requested?

2170

Proceed with

existing

evidence

items?

GOTO

1210

Capacity

Assessment

YES

NO

NO

YES

2180

Discontinue

evidence

receiving and

proceed PAP

2150

Communicate with customer

- Request Additional

Evidence

- Clarification onService

requested

2110

Isaccessto additional information

such as autopsy reports, police reports, or

crime scene reports, necessary for

evaluating the case request?

NO

YES

2120

Evaluate or make

request for the

necessary

information

NO

YES

2200 CaseAssessment

2220

Based on Case

information/PAP,

determine what samples

to test and in which

order (TestingPlan)

2205

Input:

Cataloged

evidence items

2230

Output:

Evidence Testing Plan

(i.e. priority list)

FactorsWhen Determining

TestingPlan

(e.g. which itemsand how many will be

processed and in which order?)

- Administratively chosen

- Customer driven

- Investigative driven

- Random order

- Perceived probative value based

on examinersopinion

- Sequential order

- Processed based on grouping

- Crime Type

Use the following questions to

determine next steps:

- Review unknownsbefore

firearms?

- Were only unknownssubmitted

for examination?

- Analyze all unknowns?

- Will sampling plan be applied

(such asICD)?

GOTO3100

Item

Determination

FROM

1290/1295

2105

Input: Evidence item(s) forwarded to assigned examiner

- Firearms/ FirearmsParts

- Projectile (Bulletsand Shot)

- Shotshell Components

- Cartridge Case/Shotshell

- Live /Unfired Ammunition

- Other Items
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE5 FirearmsProcess Map (Current Practice)

3100 Item Determination

GOTO

3800

Projectile/Bullets

GOTO

3600

Cartridge Case/Shot

Shell

GOTO4100

Render Firearm

Safe or 4200

Functionality

PAP

GOTO

3400

Live/Unfired

Ammunition

Technology Assist

- Camera

- LIMS

- Magnifier

- Flashlight

- Magnet

- Tool Kit

- Reference Material: Partsand Firearms

- Reference Material: Literature

3300

Is it Live/Unfired

Ammunition?

3310

Is it shotshell

components?

3320

Isit a projectile

(Bullets/Shot)?

3330

Is thisa cartridge

case/shotshell?

3340

Isthis afirearm?

3120

Open packaging

3190

Visual Examination to

characterizesample

type Document PAP

3160

Isit a single

item?

3130

Document and/or

Photograph Per

Agency Policy (PAP)

3170

Inventory and subitemize

3140

Do the contentsmatch

the item

description?

3110

Select Item per

evidence testing

plan

3350

Isthis afirearm

part(s)?

3360

Items not consistent with

componentsof afirearm or

ammunition (egdebrisor

other items)

3200

Label PAP?

3210

Label itemsas YES appropriate

NO

3150

Can case

continue?

NO

3105

Input:

Evidence testing

plan and

evidence items

NO

YES

YES

NO

YES

DetermineSample Type FeatureAssessment

3145

Communicate with

customer

and/or process

contentsPAP

3180

Label item as

appropriatePAP

GOTO

3800

Projectile/Bullets

GOTO

4100

Render

Firearm Safe

FROM

2230/7085/

7145/7290/

7569/7590/

7680

3220

UpdateEvidence

TestingPlan based

on case information

PAP

Return to Overview

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Return to

3100 (Item

Determination)

Y

N

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE6 FirearmsProcess Map (Current Practice)

3400 Feature Assessment: Live/Unfired Ammunition

3485

Try enhancement

techniquesto aid in

comparison?

3455

Suitable for

comparison?

3440

Will there be a

comparison of

toolmarks?

GOTO

7800

Comparison

Cto F

3495

Evaluate suitability

for comparison

Return to Overview

Technology Assist

- Camera

- LIMS

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscopeetc)

- Flashlight

- Magnet

- CastingMaterial

- Reference Material: Literature

- General RiflingCharacteristics Database

- Ammunition Reference Collection

- Measuringtool

(Caliper/ruler/micrometersetc)

3425

Group by Class Characteristicsand

update testingplan

3420

Multiple Items?

NO

3410

Document Per

Agency Policy (PAP)

(Descriptive and/or Detailed Toolmark

Documentation)

3415

Mark evidence with

identifiers PAP

YES

GOTO

7500

Comparison

Cto C

YES

NO

YES

NO

Enhancement Techniques

- Magnesium smoking

- Casting

- Sharpie

3430

Determine if live

ammunition issimilar in

descriptive featuresto

fired

ammunition?

YES

NO

3405

Input:

Live/Unfired

Ammunition

Descriptive Documentation Through Direct

Observation - Live/Unfired Ammunition

- Photograph Documentation (Agency Dependent)

- Visual Examination for Trace Evidence (Collect?

Decontaminate?)

- Determine Cartridge Caliber

- reference material

- experience

- measurement

- Determine cartridge/ shot shell Manufacturer / Marketer

- Determine projectile Type (HP, FMJ)

- Determine composition of: Primer, Case, Bullet, battery

cup (Based on Color or MAGNET)

- Document Headstamp on Cartridge

- Document Cannelures

- Document Sealant

- Document Hull Marks(Shot Shells)

- Ignition System (Rimfire/Centerfire)

- Shotshell length

Detailed Toolmark Documentation

(Comparable Features)- Live/Unfired

Ammunition

- Reloading Marks

- Manufacturing Marks

- Light Strikes- primer

- Bunter Marks

- Feed Ramp Marks

- Magazine Marks

- Chamber Marks

- Ejection Port Marks

- Extractor Marks

- Ejector Marks

- Shell Stop Marks

NO

YES

3460

Are there multiple

cartridges?

3465

Select sample PAP YES

NO

3470

Are the marksof

interest on the

projectile?

3475

Isthere a

firearm?

YES YES

GOTO

7300

Comparison

Pto F

NO

*

3500

Is there a

firearm?

GOTO

7100

Comparison

PtoP

NO

YES

NO

NO

YES YES

NO

*It isimplied/understood here that

if the mark isn't on the projectile, it

ison the cartridge case. 3510

If multiple cartridges,

will there be intercomparison

prior to test fire

comparison?

3480

If multiple projectiles, will there be

intercomparison prior to

test fire

comparison?

GOTO

5100

Subclass

3445

Evaluate and

document suitability

PAP

3435

Comparedescriptive

featuresand

Document PAP

3490

Enhancement

techniquesand

document/

photograph PAP

FROM

3300

3512 Output: Cartridgessuitable for

comparison, where the markingsof interest areon

the cartridge case, there will

not be an intercomparison,

and there isa firearm

present

3525 Output: Cartridgessuitable for

comparison, where the markingsof interest areon

the projectile, there will be

an intercomparison, and

there is a firearm present

3505 Output: Cartridgessuitable for

comparison, where the markingsof interest are

on the cartridge case,

and there is no firearm

present

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Is there more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

3530 Output: Cartridgessuitable for

comparison, wherethe markings of interest are

on the projectile, and

there is no firearm

present

3520 Output: Cartridgessuitable for

comparison, where the markings of interest are on

the projectile, there will not

be an intercomparison, and

there isa firearm present

3515 Output: Cartridgessuitable for

comparison, where the markingsof interest areon

the cartridge case, there will be an intercomparison,

and there isa firearm

present

3450

Evaluate for

Subclass?

YES

NO

3417

Will there be

examinationsof

live/unfired

ammunition?

YES

NO
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE7 FirearmsProcess Map (Current Practice)

3600 Feature Assessment: Cartridge Cases/Shotshells

3655

Will there be entry into

ICDprior to comparison?

(PAP)

3715

Suitable for

comparison?

3725

Are there test fires with the same class

characteristics

available?

GOTO

7800

Comparison

Cto F

3735

Try enhancement

techniques to aid in

comparison?

3640

Evaluate and

document suitability

PAP

3660

Select itemsfor

entry

3635

Evaluate item for

suitability? Individual

Characteristic Database

(ICD), or

comparison?

3685

Enter information

into General Rifling

Characteristics(GRC)

database?

3650

Enter into ICD?

3680

Will there be a

comparison of

toolmarks?

3730

If multiple, will

there be intercomparison

prior to test fire

comparison?

3745

Evaluate suitability

for comparison

3695

Report results?

3700

Document/Report

GRCresultsPAP

3690

Launch Search

3665

ENTERINTO

ICDPAP

3740

Enhancement

techniques and

document/photograph

PAP

Descriptive Documentation Through Direct

Observation? Cartridge Case/Shotshell

Detailed Toolmark Documentation- Cartridge

Case/Shotshell

Return to Overview

- Photograph Documentation (Agency Dependent)

- Visual Exam for TraceEvidence (Collect?Decontaminate?)

- Cartridge Caliber/Gauge

- Cartridge Manufacturer / Marketer

- Composition (Primer, Case, Battery Cup)

- Design / Type (high brass, low brass?)

- Cannelures

- Sealant

- Condition (Isit mutilated?Doesit require manipulation?)

- Info on Hull

- Manufacturer or Marketer

- Ignition System (Rimfire/Centerfire)

- Shotshell length

- Nominal Caliber

- Visual Examination: reference material (direct comparison),

experienced analyst

Note Type:

- Headstamp

- Straight, rim, rimless, rebated,

- Measurement (cartridgesof the world - book)

- Diameter: Mouth, Shoulder, rim, neck,

- Rim thickness

- Length

- Document general class characteristics, location, and shape:

- FiringPin Impression

- Breech Face Marks

- FiringPin Aperture

- Anvil (rim fire)

- Extractor

- Ejector

- Chamber Marks

- Ejection Port Marks

- Reloading Marks

- Cycling Marks

- Chambering Marks

- Magazine Lip Marks

- Manufacturing Marks/ Features

- Light Strikes

- Bunter Marks

Technology Assist

- Camera

- LIMS

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscope etc)

- Flashlight

- Magnet

- Casting Material

- Reference Material: Literature

- General RiflingCharacteristicsDatabase

- Ammunition Reference Collection

- Measuring tool

(Caliper/ruler/micrometersetc)

3632

Group byClass Characteristicsand

update testingplan

3630

Multiple FCC/SHOT

SHELL?

NO

3610

Document Per

Agency Policy (PAP)

(Descriptive and/or Detailed Toolmark

Documentation)

3620

Mark evidence with

identifiersPAP

YES

3645

Will there bea

comparison made?

YES

YES

YES

NO

NO

YES

GOTO

7500

Comparison

Cto C

YES

NO

NO

YES

YES

NO

YES

NO

NO

NO

YES

NO

3605

Input:

Fired Cartridge Cases/Shotshells

Enhancement Techniques

- Magnesium smoking

- Casting

- Sharpie

YES

NO

3670

Determine if live ammunition issimilar

in descriptive featuresto fired

ammunition?

YES

NO

3675

Comparedescriptive

featuresand

Document PAP

NO

YES

GOTO

5100

Subclass

3720

Evaluate for

Subclass?

YES

NO

FROM

3330

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

3750

Output:

Fired cartridge casesor

shotshellssuitable for

comparison, where there

are not test fireswith the

same classcharacteristics

available

3755

Output:

Fired cartridge casesor

shotshellssuitable for

comparison, wherethere

are test fireswith the

same class characteristics

available, and there will

beintercomparison

3760

Output:

Fired cartridge casesor

shotshellssuitable for

comparison, wherethere

are test fireswith the

same class characteristics

available, and there will

not be intercomparison
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE8 FirearmsProcess Map (Current Practice)

3800 Feature Assessment: Projectiles/Bullets

3915

Are there test fires with the sameclass

characteristics

available?

3835

Will there be entry into

ICDprior to comparison?

(PAP)

3895

Document GRC

resultsPAP

3945

Evaluate suitability

for comparison

3855

Select itemsfor

entry

GOTO

7300

Comparison

Pto F

3905

Suitable for

comparison?

3860

ENTERINTO

ICDPAP

3890

Report Results?

3840

Evaluate and

document suitability

PAP

3850

Enter into ICD?

3925

Try enhancement

techniquesto aid in

comparison?

3920

If multiple, will there

be intercomparison

prior to test fire

comparison?

3885

Launch Search

3875

Will there be a

comparison of

toolmarks?

3940

Enhancement

techniques and

document/photograph

PAP

3830

Evaluate item for

suitability? Individual

Characteristic Database

(ICD), or

comparison?

Return to Overview

Technology Assist

- Camera

- LIMS

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscope etc)

- Flashlight

- Magnet

- Casting Material

- Reference Material: Literature

- General RiflingCharacteristicsDatabase

- Ammunition Reference Collection

- Measuring tool

(Caliper/ruler/micrometersetc)

- Balance/Scale

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Return to

Item

Determination

Y

N

3825

Group by Class Characteristicsand

update testing plan

3820

Multiple Items?

NO

3810

Document Per

Agency Policy (PAP)

(Descriptive and/or Detailed Toolmark

Documentation)

3815

Mark evidence with

identifiersPAP YES

3845

Will there bea

comparison made?

YES

YES

NO

NO

YES

GOTO

7000

Comparison

PtoP

YES

NO

YES

YES

NO

YES

NO

NO

NO

YES

NO

3805

Input:

Fired

Projectiles/Bullets/

Shotshell

Components

Enhancement Techniques

- Magnesium smoking

- Casting

- Sharpie

YES

NO

3865

Determine if live

ammunition issimilar

in descriptive features

to fired

ammunition?

YES

NO

3870

Compare descriptive

featuresand

Document PAP

NO

YES

- Photograph Documentation (Agency Dependent)

- Visual Exam for Trace Evidence (Collect?

Decontaminate?)

- Composition

- Design/Type (round nose, hollow point, etc.)

- Cannelures(number and type)

- Characteristicsof Base

- Condition (Isit mutilated?Doesit require manipulation?)

- Wad/shot cup or other internal portionsof shotshell

present (paper wad, shot buffer, etc.)-

- Jacket Manipulation (If needed)

- Manufacturer or Marketer

- Nominal Caliber/Gauge/Bore

- Weight

- Diameter

- RiflingCharacteristics

- Visual Examination: reference material,

experienced analysis

- Cycling Marks

- Manufacturing Marks/ Features

- Case Mouth Marks

- Number of Petals

- Mould Marks

- Shot Dimples

- Other Toolmarks

- Other Measurements

Descriptive Documentation Through

Direct Observation?

Projectiles/Bullets/Shotshell

Components

Detailed Toolmark Documentation ?

Projectiles/Bullets/Shotshell Components

NO

3910

Evaluate for

Subclass?

GOTO

5100

Subclass

YES

NO

YES

FROM

3310/3320

3880

Enter information

into General Rifling

Characteristics(GRC)

database?

2500 Evidence TestingPlan

3950

Output:

Fired projectiles, bullets,

or shotshell components

suitable for comparison, wherethere are not test

fireswith the same class

characteristicsavailable

3955

Output:

Fired projectiles, bullets, or

shotshell componentssuitable

for comparison, wherethere

are test fireswith the same

class characteristicsavailable,

and there will be

intercomparison

3960

Output:

Fired projectiles, bullets, or

shotshell components

suitable for comparison, wherethere aretest fireswith

the same class characteristics

available, and there will not

be intercomparison

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE9 FirearmsProcess Map (Current Practice)

4100 Render Firearm Safe

GOTO

9000

Other

Examintions

4140

Isthe firearm

Loaded?

4170

Unload Firearm

4180

Document and

Photograph

PAP

4150

Can the firearm be

unloaded through non

-destructive means?

4105

Input: Firearm

YES YES

NO

4135

Document

PAP

Technology Assist

- Camera

- LIMS

- BoreScope

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscope etc

- Flashlight

- Tool Kit

- Reference Material: Partsand Firearms

- Reference Material: Literature

NO

4110

Examiner familiar with the

firearm?

NO

4120

Consult Reference Material or another

Examiner and

Document PAP

4125

Document/Photograph/

Collect TraceEvidence/Swab

for DNAprior to rendering

firearm safe?

YES

4155

Unload Firearm by

least destructive meansnecessary

PAP

4160

Can the process

continuewith

undamaged

parts?

YES

NO

NO

4115

Consult reference material or another

examiner?

YES

NO

4145

Output:

Unloaded

firearm or

firearm parts

4165

Document PAP

4130

Photograph/Collect

trace evidence/swab

for DNA Per Agency

Policy (PAP)

4191

Will functionality

testingand/or test

fire be

conducted?

YES

GOTO

4200

Functionality

4195

Will other

examinations be

conducted?

YES

NO

STOP/RETURN

EVIDENCE/

Document PAPor

go to 2500

(EvidenceTesting

Plan)

Initial Examination

Document any pertinent

observations:

- Scratches

- Rust

- Defects

- Modifications

- Missing/broken parts

- Trace material

- Misc. (or otherwise

noteworthy features)

4190

Inspect General

Condition of the

Bore (obstructions

or defects)

FROM

3340/3350 YES

Return to Overview

QUALITATIVEEVALUATION:

- ManipulateAction

- Dry Fire

- Trigger Pull ?

(Qualitative)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

4185

Conduct/Document

Initial

Examination?

NO

4187

Conduct Initial

Examination

YES

NO
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE10 FirearmsProcess Map (Current Practice)

4200 Functionality

Field Strip/Detailed

Disassembly

4324

Conduct Trigger Pull

Measurement?

Return to Overview

Descriptive Documentation: ClassCharacteristics:

NOTE: Multiplesafety and

functionality stepsare

interchangeable. Some are

sequential, othersare

simultaneous, some order

isagency specific.

4321

Conduct Impact

Test?

4345

Is it operating as

designed?

4350

Can the firearm

be safely fired?

NO

- Damage

- Use/Wear

- Safety

- Chamber Modification

- Action Type

(Modification)

- Other

Technology Assist

- Camera

- LIMS

- Balance

- BoreScope

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscopeetc

- Flashlight

- Magnet

- CastingMaterial

- Tool Kit

- Reference Material: Partsand Firearms

- Reference Material: Literature

- General RiflingCharacteristics Database

4205

Input:

Firearm

Rendered Safe

4235

Document (alsosee

list Descriptive Documentation

and/or Class Characteristics)

PAP

4215

Isthisa complete

firearm?

4220

Are the necessary

reference parts

available for the

firearm?

YES

4240

Doesthe firearm

appear to be

operating?

4245

Continue?

NO

YES

NO

YES

4275

Attempt to fix

issue?

4280

Fix issue Document/Photograph

PAP

YES

NO

4225

Are test standards

(TS) needed?

4290

Can standardsbe

created through alternative means

(cast, push a bullet,

etc)?

NO

YES

4322

Conduct Capacity

Test?

4323

Measure

Barrel/Overall

length?

4326

AssessAction

Type?

YES

4360

SAFETYRECALL: CHECKRELEVANT

REFERENCE

MATERIALPAP

4365

Is there any issue that will

affect the examination that warrants

troubleshooting?

YES

4320

CheckSafety

Recall?

YES

4325

ExamineSafety

Mechanism(s)?

4330

DOCUMENT

RESULTSOFANY

FUNCTIONALITY

ANDSAFETYTESTS

PAP

NO

YES

YES

Functionality andSafety Tests

NO

GOTO

4260

TROUBLESHOOT

YES

GOTO

4260

TROUBLESHOOT

- Breech or Bolt Face

- FiringPin Aperture

- FiringPin Detail

- Ejector / Extraction

- Rifling

- Caliber

- Serial Number

- Make

- Model

- Importer

- Manufacturer

- Caliber

- Modifications(Visual/External/Dimensional)

- Firearm Type (Shotgun, revolver, etc.)

- Accessories(Visual)

- Safety Mechanisms

- Condition (Rust, Scratches, Other Damage etc)

NO

YES

4340

Output: Firearm

ready for test fire;

Documented results

for the relevant

functionality test(s)

performed

Trigger Pull

- Spring Scale

- Digital Scale

- Weights

4210

Photograph

condition asreceived/Collect

Trace Evidence/Swab

for DNA?

4230

Photograph/Collect

trace evidence/swab

for DNAPer Agency

Policy (PAP)

4295

Create test standard

through alternative methods

4310

Will these standardsbe

used for

examination?

GOTO6000

OR7000 PAP

YES

NO

NO

YES

GOTO

4500

Test Fire

GOTO

4225

Are test

standards

needed?

4347

Evaluate for

subclass?

YES

GOTO

5100

Subclass

NO

NO

YES

GOTO

9600

Barrel/Overall

Length

4260

TROUBLESHOOTING

STEPSPAP:

-field strip

-detailed strip

-research

4265

Hasthe issue been

identified?

NO

4270

Continue

troubleshooting?

NO

YES

FROM

3350/4191

NO

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan) DOCUMENTONEORMOREOFTHEFOLLOWING:

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

4300

Output:

AlternativeTest

Standard (TS)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE11 FirearmsProcess Map (Current Practice)

4500 Test Fire

4760

Determine number

of TSs to enter into

the database

GOTO

4650 Will

there be a

comparison?

4660

ICDENTRYPAP

4740

Entry into ICD?

Label Ammunition Label Fired Components

Return to Overview

4580

Select Recovery

System:

-Water

-Cotton Box

-Kevlar Tube

4510

Can the gun be safely

fired byhand?

4565

Will projectile be

recovered?

4570

Select Non- Recoverable or

Recoverable System

(no restrictionson

system):

-Bullet Trap

-Open Range

-Other/Recoverable

-Rubber Media

System (egForensic

Buddy)

4625

Keep all test

fires?

4675

Conduct known

analysis?

NO

4690

Select sample for

comparison and

document PAP

4645

Label fired

componentswith

identifiers?

YES

4555

Label

ammunition

now?

- Label Ammunition for indexing?

- Label Ammunition for identification?

4515

Can a remote

firingsystem be

used?

YES

YES

4560

Label ammunition

and document Per

AgencyPolicy (PAP)

YES

NO

- Label fired components for indexing?

- Label fired componentsfor

identification?

4600

Document PAP

YES

4640

Determine which TF

to Keep and

document PAP

NO

4670

Label ammunition

and document PAP YES

NO

YES YES

Technology Assist - PPE

- Mallet

- RemoteFiringdevice

- Scribe (i.e Dremel)

- Sharpie, label maker, laser

engraver

- Magnification Device

(MagnifyingGlass/Comparison Microscope/Stereoscopeetc)

- Reference Library

- Stock Ammunition

NO

4520

Are test standards

(TS)

needed?

NO

NO

4525

Can TSsbe created through

alternative methods (cast, push a

bullet, etc)?

NO

YES

4530

Output:

Test Standards

4590

Execute Test Fire

Plan

4610

Visually Inspect Test

Fire

4615

Is are-shoot

necessary?

YES

NO

4725

Are features

repeatable?

YES

NO

4730

Would additional

test standards be

helpful?

YES

4505

Input:

Firearm that can

be fired

4650

Will there be a

comparison?

NO

4720

Description and/or Comparison of TS

and document

observationsPAP

4700

Is unknown

projectile available for

comparison?

YES

GOTO

7300

Comparison

Pto F

NO

GOTO

7800

Comparison

Cto F

4735

Continue with

comparison?

NO

NO

YES

YES

4655

Conduct known

analysis?

NO

YES

NO

4620

Are there any

additional functionality/other

examinationsof firearm

prior to

proceeding?

4630

Other

examinations(e.g.

Impact Test/Serial

Number

Restoration, other

functionality

testing etc.)

document

observationsPAP

YES

NO

4527

CreateAlternate TS

4535

Will these be

used for

examination

purposes?

YES

4652

Entry into ICD? YES

NO

4657

Select Sample(s)

4750

Description and/or Comparison of TS

and document

observationsPAP

NO

GOTO4800

Ammunition

Selection

4677

Evaluate for

Subclass?

YES GOTO5100

Subclass

GOTO

4800

Ammunition

Selection or

Back to 4527

Alternative Test

Standards

NO

NO

FROM

4192/4350/5210/

7390/7480/7860

FROM 4825

FROM

4880

FROM 5210

Output:

Test standards

deemed

suitable for

comparison

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

YES

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE12 FirearmsProcess Map (Current Practice)

4800 Ammunition Selection

4870

Are additional

cartridgesneeded

specifically

for ICD?

4820

Isthere any evidence

ammunition available?

4850

Can evidence ammunition be

consumed Per Agency Policy

(PAP)?

4855

Will evidence ammuniton be

consumed?

YES YES YES

NO

4825

Can stock ammunition be

obtained?

YES

YES

NO

4805

Input:

Firearm needingtest

standards(TS)

GOTO

4555

Test Fire

4880

Output:

Selected

ammunition

4830

Select stock

ammunition and

document PAP

4860

Select evidence

ammunition and

document PAP

NO

NO

GOTO

4520

Test Fire

Considerationsfor Ammunition

Selection

- Availability

- Comparison and/or ICDPurposes

- Similarity to questioned items

- Composition

- Bullet Design (likelihood of fragmentation)

- Familiarity (likelihood of reproducibility)

- ICDGuidelines/Parameters

YES

NO

FROM

4515/4510/4615/

4730

Return to Overview

4810

Determine ammunition

needs(see Considerationsfor

Ammunition Selection)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE13 FirearmsProcess Map (Current Practice)

Commentary

5100 SubclassDetermination

5170

Document Per

Agency Policy (PAP)

GOTO4500

(Test Fire)/GO

BACKTO

4720/7410/

7810

Return to Overview

5185

Isfurther evaluation

of subclassneeded based

on manufacturing

techniques?

5190

Examination

Evaluation for

Subclass(e.g.,

visual and/or

casting, which may include

disassembly).

YES YES

Technology Assist

- Camera

- LIMS

- Balance

- Bore Scope

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscopeetc)

- Measurement Projection Scope

- Flashlight

- Magnet

- Casting Material

- Tool Kit

- Reference Material: Parts and Firearms

- Reference Material: Literature

- General RiflingCharacteristicsDatabase

Considerationsfor Subclass

Determination: Toolmarks

Considerationsfor Subclass

Determination: Tools

5180

Can the most likely methodsof manufacture

be determined based on

the tool design and

toolmarks?

NO

- Coarse/Bold Detail

- Continuousmarkings(eg long continuous

toolmarks)

- Grossuniform spacing

- Mold marks

- Similarity of Pattern in other areas

- Symmetry

- How the tool movesagainst

substrate/object

- Most likely manufacturingmethod based on

tool design

- Location of tool surfaces

- Directionalityof marks

- Part lines/Mold marks

- Manufacturer literature or reference materials

- How the tool moves against

substrate/object

5110

Evaluate tool for

subclass?

5160

Evaluate Tool (See

considerations:

Tools)

NO

5120

Evaluate toolmark

(See considerations:

Toolmark)

YES

5210

Output:

Tool evaluated and

subclassfeatures

documented

From 4347

(Functionality)/

4677 (Test

Fire)/7205 (Pto

P)/7405 (Pto

F)/7605 (Cto C/

7805 (Cto F)

GOBACKTO

3465/3780/3955/

7210/7410/7607

/7810

5200

Document Subclass

EvaluationPAP

NO

5130

Visual

Examination

Evaluation for

Sub Class

5125

Isthe nature of

the markssuggestive

of subclass?

YES

5140

Document Subclass

EvaluationPAP

NO

5150

Output:

Toolmarks

evaluated and

subclass features

documented

From

3450/3720/3910

(Feature

Assessments)

5105

Input: Tool (firearm)/Projectile/Cartridge Case or

Live/Unfired Ammunition
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE14 FirearmsProcess Map (Current Practice)

7000 Comparison: Projectile to Projectile (Pto P) 1 of 2

Considerationsfor Comparison

Conclusions

Inconclusive - C

Exclusion /

Elimination

Return to Overview

7015

Set up Evidence

Itemsfor

Comparison (e.g.

comparison microscope, 3-D

scanning software

imagesetc)- See Considerationsfor

Comparison;

Optimize lighting, magnification, and

focus

7020

Compare class

characteristicsof the

two items

7040

Determine which of

the two itemsto

hold in fixed position

7025

Are the classcharacteristics

in agreement?

7050

Position fixed item

usingarea of

interest features

7060

Rotate other item to

find corresponding

area of interest

7065

Isthere a

corresponding

area of interest

(in phase)?

7070

Isthere an additional

area of interest?

YES

7130

Isthe level of

disagreement sufficient

to exclude?

YES

NO

YES

7087

Use three levelsof

inconclusive (PAP)?

NO

7135

Can exclusion be made without

Firearm?

7080

Are one of the

unknownsdescribed as

TFat time of

submission?

7082

Request the

Firearm?

7085

Request

Firearm PAP

YES YES

7010

Are one of the

unknownsdescribed

astest fire (TF) at time

of submission?

YES

NO

GOTO

7200

PTOP

(2 of 2)

Inconclusive

Inconclusive - B

Inconclusive- A

Identification

Exclusion /

Elimination

Inconclusive

Exclusion /

Elimination

7005

Input: Projectiles suitable for

comparison

NO

Technology Assist

- Computer aided comparison (3DModeling)

- Computer aided documentation

- Computer aided selection of the known / unknown to compare (NIBIN)

- Comparison Microscope

- ImagingSystem

Selectingwhich unknown or known to compare first/next:

Select the applicable criteria:

- Quality/complexity of toolmarks

- Administratively chosen

- Customer driven; investigative question

- Random order

- Perceived probative value based on examiner discretion

NO

7075

Isthere disagreement among

individual detail

present?

7100

Ableto eliminate

based on individual

detail Per Agency

Policy (PAP)?

YES YES

NO

Inconclusive - B Inconclusive - C

NO

7125

Use three levelsof

inconclusive (PAP)?

NO

Inconclusive

NO

YES

NO

NO

YES

7120

Are oneof the

unknownsdescribed as

TFat time of

submission?

YES

7140

Request the

Firearm?

7145

Request

Firearm PAP

NO NO

GOTO3100

Item

Determination

YES

7012

Treat asknowns? YES GOTO7300

(PTOF)

NO

7030

TM Selection Determinewhich toolmark/area

of interest

to compare(markingsthat the

firearm would reproduce)

-rifling

- land, groove impression

- misalignment/slippage

-feedramp marks

-forcingcone/shave marks

- Other

YES

NO

GOTO3100

Item

Determination

FROM

7210/7235

PTOP

(2 of 2)

FROM

3525/3530/

3950/3955/

4310

Enter

information into GRC?

Report results?

LaunchSearch

Document/Report

GRCresultsPAP

YES

YES

YES

NO

NO

GOTO2500

(Evidence

Testing Loop)

OR 10000

(GRC) PAP

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

10000 GRCDatabase Search *GRCsearch may be approprite

when the evidence item(s) are not identified to afirearm.

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC)PAP
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE15 FirearmsProcess Map (Current Practice)

7200 Comparison: Projectile to Projectile (Pto P) 2 of 2

7260

Evaluate and

Document CMS

7265

Does evaluated CMS meet threshold for

identification?

Conclusions

Return to Overview

7200

Evaluate level of

correspondence

in area of interest

and document

observationsPer

Agency Policy

(PAP)

7215

Mark/Index

items?

7220

Mark itemsand

document PAP

NO

YES

7230

Rotate in Phase

position to visualize

additional

corresponding

featuresuntil

complete

NO

7225

Are there additional

areasof interest to

examine?

7210

Continue reviewing in

phase?

7245

Can identification be made without

Firearm?

FROM

7065

PTOP

(1 of 2)

RETURN TO

7030

(PTOP

PAGE1)

Inconclusive - C

Exclusion /

Elimination

Inconclusive - B

Inconclusive - A

Inconclusive

YES

Identification

Inconclusive - A

Identification: Firing

NO

7250

Will CMSbeused

asacriteria for

identification?

NO

NO

YES

YES

NO

YES

7270

Use three levels

of inconclusive

PAP?

YES Inconclusive- A

NO

Inconclusive

7285

Use three levelsof

inconclusive (PAP)?

Inconclusive

7280

Request the

Firearm?

YES

7275

Are one of the unknowns

described asTFat time

of submission?

YES

7290

Request

Firearm PAP

YES

7240

Photograph/Document

PAP

YES

7235

Does thePhase

position need to be

re-evaluated?

YES

NO

RETURNTO

7030 (PTOP

PAGE1)

7295

Is the mark beingidentified a

result of the firing process?

YES

NO

Identification: Cycling/common tool or

source

NO NO

GOTO3100

Item

Determination

7255

Istheagreement

sufficient for ID?

(Qualitativeand

Quantitative)

YES

NO

NO

Enter

information into GRC?

Report results?

LaunchSearch

Document/Report

GRCresultsPAP

YES

YES

NO

NO

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

7205

Isthere potential

subclassin the

corresponding

detail?

YES

GOTO5100

SUBCLASS

NO

FROM 5150
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE16 FirearmsProcess Map (Current Practice)

7300 Comparison: Projectile to Firearm (Pto F) 1 of 2

Considerationsfor Comparison

Conclusions

Inconclusive - C

Exclusion /

Elimination

Return to Overview

7320

Optimize lighting, magnification, and

focus

7340

Determine which of

the two itemsto

hold in fixed position

7325

Are the classcharacteristics

in agreement?

7350

Position fixed item

usingarea of

interest features

7360

Rotate other item to

find corresponding

area of interest

7365

Is there a

corresponding

area of interest (in

phase)

7370

Is there an additional

area of interest?

YES

7380

Is the level of

disagreement sufficient

to exclude?

NO

YES

7395

Use three levelsof

inconclusive (PAP)?

GOTO

7400

PTOF

(2 of 2)

Inconclusive

Inconclusive - B

Inconclusive- A

Identification

Exclusion /

Elimination

Inconclusive

Exclusion /

Elimination

NO

Technology Assist

- Computer aided comparison (3DModeling)

- Computer aided documentation

- Computer aided selection of the known / unknown to compare (NIBIN)

- Comparison Microscope

- ImagingSystems

Selectingwhich unknown or known to compare first/next:

Select the applicable criteria:

- Quality/complexity of toolmarks

- Administratively chosen

- Customer driven; investigative question

- Random order

- Perceived probative value based on examiner discretion

7375

Isthere disagreement

among individual detail

present?

7377

Able to eliminate

based on individual

detail Per Agency

Policy (PAP)?

YES YES

NO

Inconclusive - C

Inconclusive - B

NO

7385

Use three levelsof

inconclusive (PAP)?

NO

Inconclusive

NO

YES

NO

YES

7330

TM Selection

Determine which toolmark/area

of interest

to compare (markingsthat the

firearm would reproduce)

-rifling

- land, groove impression

- misalignment/slippage

-feedramp marks

-forcing cone/shave marks

- Other

YES

NO

7387

Use different TSif multiple exist?YES

7390

Do new TSsneed to be

produced?

NO

YES

GOTO

4500

Test Fire

NO

7305

Input: Projectile and

Test Standard (TS) Suitable for Comparison

FROM

7410/7435/7475

PTOF

(2 of 2)

RETURNTO

7330

TM Selection

FROM

3520/3960/

4310/4700/

7012

YES

Document/Report

GRCresultsPAP

LaunchSearch

Enter

information into GRC?

Report results?

YES

YES

NO

NO

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

7310

Set up Evidence

Itemsfor Comparison (e.g.

comparison microscope, 3-D

scanning software

imagesetc)- See Considerationsfor Comparison;

Optimize lighting, magnification, and

focus
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE17 FirearmsProcess Map (Current Practice)

7400 Comparison: Projectile to Firearm (Pto F) 2 of 2

7450

Evaluate and

Document CMS

7455

Doesevaluated

CMSmeet

threshold for

identification?

Conclusions

Return to Overview

7400

Evaluate level of

correspondence

in area of interest

and document

observationsPer

Agency Policy

(PAP)

7415

Mark/Index

items?

7420

Mark itemsand

document PAP

NO

YES

7430

Rotate in Phase

position to visualize

additional

corresponding

featuresuntil

complete

NO

7425

Are there additional

areasof interest to

examine?

7410

Continue reviewing in

phase?

FROM

7365

PTOF

(1 of 2)

RETURN TO

7330 TM

Selection

(PTOF

PAGE1)

Inconclusive - C

Exclusion /

Elimination

Inconclusive - B

Inconclusive - A

Inconclusive

NO

YES

Identification

Inconclusive- A

Identification: Firing

NO

NO

7445

Will CMSbe used

asa criteria for

identification?

NO

YES

YES

NO

YES

7460

Use three levels

of inconclusive

PAP?

YES Inconclusive- A

NO

Inconclusive

7485

Use three levelsof

inconclusive (PAP)?

Inconclusive

7440

Photograph/Document

PAP

YES

7435

Does thePhase

position need to be

re-evaluated?

YES

NO

7470

Isthe mark being identified a

result of the firingprocess?

YES

NO

Identification:

Cycling/common tool or

source

7475

Use different test

standard (TS) if multiple TSs

exist?

7480

Do new TSsneed to be

produced?

GOTO

4500

Test Fire

YES

YES

NO

7465

Isthe agreement

sufficient for ID?

(Qualitative and

Quantitative)

YES

NO

RETURN TO

7330

TM Selection

(PTOF

PAGE1)

RETURNTO

7330 TM

Selection

(PTOF

PAGE1)

NO

Report results?

LaunchSearch

Enter

information into GRC?

Document/Report

GRCresultsPAP

YES

YES

NO

NO

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

7405

Isthere potential

subclassin the

corresponding

detail?

GOTO5100

SUBCLASS

YES

FROM 5150

OR5210
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE18 FirearmsProcess Map (Current Practice)

7500 Comparison: Cartridge Case to Cartridge Case (Cto C) 1 of 2

Considerationsfor Comparison

Conclusions

Inconclusive - C

Exclusion /

Elimination

Return to Overview

7515

Optimize lighting, magnification, and

focus

7530

Determine which of

the two itemsto

hold in fixed position

7520

Are the class

characteristicsin

agreement?

7535

Position fixed item

usingarea of

interest features

7540

Maneuver other

item to find

corresponding area

of interest

7545

Isthere a

corresponding

area of interest (in

phase)

7550

Isthere an additional

area of interest?

YES

7575

Isthe level of

disagreement sufficient

to exclude?

YES

NO

YES

7570

Use three levelsof

inconclusive (PAP)?

NO

YES

7580

Can exclusion be made without

Firearm?

7560

Are one of the

unknownsdescribed as

TFat time of

submission?

7567

Request the

Firearm?

7569

Request

Firearm PAP

YES YES

7505

Are one of the

unknownsdescribed as

test fire (TF) at time of

submission?

YES

NO

GOTO

7600

CTOC(2 of

2)

Inconclusive

Inconclusive - B

Inconclusive- A

Identification

Exclusion /

Elimination

Inconclusive

Exclusion /

Elimination

NO

Technology Assist

- Computer aided comparison (3DModeling)

- Computer aided documentation

- Computer aided selection of the known / unknown to compare (NIBIN)

- Comparison Microscope

- ImagingSystems

Selectingwhich unknown or known to compare first/next:

Select the applicable criteria:

- Quality/complexity of toolmarks

- Administratively chosen

- Customer driven; investigative question

- Random order

- Perceived probative value based on examiner discretion

NO

YES YES

7555

Isthere disagreement

among individual detail

present?

NO

7565

Ableto eliminate

based on individual

detail Per Agency

Policy (PAP)?

NO

Inconclusive - C

NO

Inconclusive - B

NO

7595

Use three levelsof

inconclusive (PAP)? YES

Inconclusive

NO

NO

YES

YES

7585

Are oneof the

unknowns described as

TFat time of

submission?

7587

Request the

Firearm?

NO

NO

7590

Request

Firearm PAP

GOTO3100

Item

Determination

YES

YES

NO

7507

Treat asknowns?

GOTO7700

(CTOF)

YES

NO

7525

TM Selection Determinewhich toolmark/area

of interest

to compare

- FiringPin Impression

- Breech Face Marks

- FiringPin Aperture

- Anvil (rim fire)

- Ejector Marks

- Extraction Marks

- Ejection port marks

- Chamber Marks magazine marks Other

GOTO3100

Item

Determination

7500

Input: Cartridge Casessuitable for

comparison

FROM

7605/7620

CTOC

(2 of 2)

FROM

3505/3515/3750/

3755/4310

Enter

information into GRC?

Report results? Document/Report

GRCresultsPAP

YES LaunchSearch

YES

NO

NO

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

2500 Evidence TestingPlan

GOTO

REPORTING

Is there more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

7510

Set up Evidence

Itemsfor Comparison (e.g.

comparison microscope, 3-D

scanning software

imagesetc)- See Considerationsfor Comparison;

Optimize lighting, magnification, and

focus
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE19 FirearmsProcess Map (Current Practice)

7600 Comparison: Cartridge Case to Cartridge Case (Cto C) 2 of 2

7635

Evaluate and

Document CMS

7640

Doesevaluated CMS meet threshold for

identification?

Conclusions

Return to Overview

7600

Evaluate level of

correspondence

in area of interest

and document

observationsPer

Agency Policy

(PAP)

7610

Mark/Index

items?

7615

Mark itemsand

document PAP

NO

YES

NO

7620

Are there additional

areasof interest to

examine?

7625

Can identification be made without

Firearm?

FROM

7545

CTOC

(1 of 2)

Inconclusive - C

Exclusion /

Elimination

Inconclusive - B

Inconclusive - A

Inconclusive

NO

YES

Identification

Inconclusive- A

Identification: Firing

NO

7630

Will CMSbeused

asa criteriafor

identification?

NO

YES

NO

YES

7645

Use three levels

of inconclusive

PAP?

YES Inconclusive- A

NO

Inconclusive

7685

Use three levelsof

inconclusive (PAP)?

Inconclusive

7675

Request the

Firearm?

7670

Are one of the

unknownsdescribed as

TFat time of

submission?

YES

YES

7680

Request

Firearm PAP

YES

YES

7655

Is the mark being identified a

result of the firing process?

YES

Identification: Cycling/common tool or

source

NO

NO

NO

GOTO3100

Item

Determination

7650

Isthe agreement

sufficient for ID?

(Qualitativeand

Quantitative)

NO

YES

NO

RETURNTO

7525 TM

Selection

(CTOC

PAGE1)

RETURN TO

7525 TM

Selection

(CTOC

PAGE1)

Document/Report

GRCresultsPAP

Report results?

LaunchSearch

Enter

information into GRC?

YES

YES

NO

NO

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

FROM 5150

7605

Isthere potential

subclassin the

corresponding

detail?

7607

Continue? YES

NO

GOTO5100

SUBCLASS

YES
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE20 FirearmsProcess Map (Current Practice)

7700 Comparison: Cartridge Case to Firearm (Cto F) 1 of 2

Considerationsfor Comparison

Conclusions

Inconclusive - C

Exclusion /

Elimination

Return to Overview

7715

Optimize lighting, magnification, and

focus

7730

Determine which of

the two itemsto

hold in fixed position

7720

Are the classcharacteristics

in agreement?

7740 Position fixed

item usingarea of

interest features

7750

Maneuver other

item to find

corresponding area

of interest

7755

Is there a

corresponding

area of interest

(in phase)

7760

Is there an additional

area of interest?

YES

7775

Is the level of

disagreement sufficient

to exclude?

YES

NO

YES

7795

Use three levelsof

inconclusive (PAP)?

GOTO

7800

CTOF

(2 of 2)

Inconclusive

Inconclusive - B

Inconclusive- A

Identification

Exclusion /

Elimination

Inconclusive

Exclusion /

Elimination

7705

Input: Cartridge Casessuitable for

comparison

NO

Technology Assist

- Computer aided comparison (3DModeling)

- Computer aided documentation

- Computer aided selection of the known / unknown to compare (NIBIN)

- Comparison Microscope

- ImagingSystems

Selectingwhich unknown or known to compare first/next:

Select the applicable criteria:

- Quality/complexity of toolmarks

- Administratively chosen

- Customer driven; investigative question

- Random order

- Perceived probative value based on examiner discretion

7765

Isthere disagreement among

individual detail

present?

7770

Able to eliminate

based on individual

detail Per Agency

Policy (PAP)?

YES YES

NO

Inconclusive - C

Inconclusive - B

NO

7780

Use three levelsof

inconclusive (PAP)?

NO

Inconclusive

NO

YES

NO

YES

YES

NO

7785

Use different test

standard (TS) if multiple TSs

exist?

YES

7790

Do new TSsneed to be

produced?

NO

YES

GOTO

4500

Test Fire

NO

7725

Determine which

toolmark/area of interest

to compare

- FiringPin Impression

- Breech Face Marks

- FiringPin Aperture

- Anvil (rim fire)

- Ejector Marks

- Extraction Marks

- Ejection port marks

- Chamber Marks magazine marks Other

FROM

7810/7825/7855

CTOF

(2 of 2)

RETURNTO

7725

TM Selection

FROM

3512/3760/4310/

4710/7507

Report results?

LaunchSearch

Enter

information into GRC?

Document/Report

GRCresultsPAP

YES

YES

NO

NO

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

Testing Loop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

7710

Set up Evidence

Itemsfor Comparison (e.g.

comparison microscope, 3-D

scanning software

imagesetc)- See Considerationsfor Comparison;

Optimize lighting, magnification, and

focus
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE21 FirearmsProcess Map (Current Practice)

7800 Comparison: Cartridge Case to Firearm (Cto F) 2 of 2

7840

Doesevaluated CMS meet threshold for

identification?

7835

Evaluate and

Document CMS

Conclusions

Return to Overview

7800

Evaluate level of

correspondence

in area of interest

and document

observationsPer

Agency Policy

(PAP)

7815

Mark/Index

items?

7820

Mark itemsand

document PAP

NO

YES

NO

7825

Are there additional

areasof interest to

examine?

7810

Continue reviewing in

phase

FROM

7755

CTOF

(1 of 2)

Inconclusive - C

Exclusion /

Elimination

Inconclusive - B

Inconclusive - A

Inconclusive

NO

YES

Identification

Inconclusive- A

Identification: Firing

NO

NO

7830

Will CMSbe used

asa criteria for

identification?

NO

YES

YES

NO

YES

7845

Use three levels

of inconclusive

PAP?

YES Inconclusive- A

NO

Inconclusive

7865

Use three levelsof

inconclusive (PAP)?

Inconclusive

YES

7870

Is the mark being identified a

result of the firing process?

YES

NO

Identification: Cycling/common tool or

source

7855

Use different test

standard (TS) if multiple TSs

exist?

7860

Do new TSsneed to be

produced?

GOTO

4500

Test Fire

YES

NO

YES

NO

7850

Isthe agreement

sufficient for ID?

(Qualitative and

Quantitative)

YES

NO

RETURNTO

7725 TM

Selection

(CTOF

PAGE1)

RETURN TO

7725 TM

Selection

(CTOF

PAGE1)

RETURNTO

7725 TM

Selection

(CTOF

PAGE1)

Enter

information into GRC?LaunchSearch

Report results? Document/Report

GRCresultsPAP

YES

YES

NO

NO

GOTO1500

(Evidence

Testing Loop)

OR1600 (GRC)

PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

GOTO2500

(Evidence

TestingLoop)

OR10000

(GRC) PAP

10000 GRCDatabase Search * GRCsearch may be approprite

when the evidenceitem(s) are not identified to a firearm.

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 EvidenceTestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)

GOTO5100

SUBCLASS

7805

Isthere potential

subclassin the

corresponding

detail?

YES

FROM 5150

OR5210
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE22 FirearmsProcess Map (Current Practice)

9100 Serial Number Restoration

Destructive Methods

9125

Attempt to

restore?

9110

Document rationale

and/orresearchPer

AgencyPolicy(PAP)

9120

Determine and

document method

of obliteration

9180

Select and apply destructive

technique based on

experience or PAP

9170

Document Results

and verifyPAP

9140

Document Research

(i.e. structure, isit

hidden: location,

composition e.g.

location, ferrousv

non-ferrousmetal)

9130

Document/Report

Per AgencyPolicy

(PAP)

9105

Should the fiream

have a serial

number?

Input: Firearm with request for serial

number restoration or observable

obliteration

NO

YES

NO

YES YES

- Chemical

- Heat

- Electrochemical Etching

- Polishing

9150

Determine and

document whether

ferrous/non-ferrous

9155

Use

non-destructive method?

9160

Select and apply

non-destructive technique

based on experience or PAP

YES

NO

9190

Document Results

and verify PAP

9195

Use another

restoration method?

GOTO

8000

Reporting/

Verification

NO

YES

Non- Destructive Methods

- Magnaflux (Magnetic particle

inspection)

- Infrared imaging/ALS

- ScanningElectron

Microscope (SEM)

- Acetone/ Cleaning

- Barcode/QRDeciphering

Technology Assist

- Camera

- Magnification Device (Magnifying

Glass/Comparison Microscope/Stereoscope

etc)

- Flashlight/Light Source

- Magnet

- Electrochemical Power Source

- Dremel/Rotary Tool

FROM 4195

Return to Overview

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE23 FirearmsProcess Map (Current Practice)

9600 Barrel Length/Overall Measurement

RETURNTO

4240

Functionality

9605

Input: Firearm Rendered Safe

YES

9650

Report

uncertainty?

YES

NO

9660

Report/Document

uncertaintyPer

AgencyPolicy (PAP)

9620

Use a tool with

calculated measurement

uncertainty?

NO

Technology Assist

- Calibrated Measurement Device

- Measurement Device

FROM 4323

Return to Overview

9670

Isexamination

complete?

NO

YES

9680

Report Barrel Length

STOP/

Document PAP

or go to 2500

(Evidence

TestingPlan)

2500 Evidence TestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Return to

3100 (Item

Determination)

Y

N

9630

Measure and

Document

9640

Measureand

document using

tool with calculated measurement

uncertainty
OSACFirearmsand ToolmarksSubcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication Date January 7, 2021 PAGE24 FirearmsProcess Map (Current Practice)

Return to Overview 8000 ? Reporting andVerification

8010

Generate Draft

Report

8020

IsVerification

Required

8025

Will verification

be requested

8040

Identify Verifying

Examiner

8030

Doesthe examiner

choose the verifier?

YES

NO

8100

Generate draft

report

8125

IsTechnical Review

Required?

8135

IsAdmin Review

Required?

NO

8130

TECHNICAL

REVIEW

YES

8140

ADMIN

REVIEW

YES

8055

Conduct Blind

Verification?

8075

Do the examiners

have consensus

agreement?

NO

8070

VERIFICATION

YES

8085

Examination

Complete?

GOTO

2500

Evidence

Testing

Plan

NO

8005

Draft report prior to

verification?

YES

8080

Conflict

Resolution PAP

NO

NO

8035

VerifyingExaminer

selected Per Agency

Policy (PAP)

8045

Does the evidence

remain in the custody

of the

examiner?

8050

Transfer Evidence to

the custody of the

verifier

NO

YES

8060

Share casedataPAP

NO

YES

NO

8090

Hasa draft report

been generated?

YES YES

NO

YES

8095

Doesthe draft

report need to be

updated?

8110

Update draft report YES

8120

Finalize Report

NO

NO

8000

Input: Documentation of Completed

Examinations

YES

Considerationsfor Conflict Resolution

- Request new exam

- Request verification

- Bring in other examiners(eg. Supervisor, Q/A,

Tech lead etc)

- Consultation

- Report no conclusion, multiple conclusions,

report asconcensusconclusion.

Considerationsfor Verification

- DoesExaminer Mount Evidence for Verifying

Examiner?

- DoesExaminer provide examination documentation to

Verifying examiner?

- DoesExaminer provide conclusion of comparison to

Verifying examiner?

- Will case be completely reworked by another

examiner or via additional/different methods?

DISSEMINATE

REPORT TO

REQUESTOR

2500 EvidenceTestingPlan

GOTO

REPORTING

Isthere more evidence

to examine per

testing

plan?

Y

N

Return to

3100 (Item

Determination)
OSACFirearmsand Toolmarks

Subcommittee

This process map provides a visual description and attempts to represent all reasonable variations of casework currently performed by firearm examiners. OSAC

and AFTE do not necessarily support or endorse (as best practices) all of the different steps and paths depicted in this process map.

Editorial Update November 22, 2022

Original Publication January 7, 2021

Page 25

FirearmsProcessMap

(Current Practice)

Glossary of Termsand Definitions*

General ClassCharacteristics (AFTETerminology): Measurable featuresof a

specimen which indicate a restricted group source. They result from design

factors, and are therefore determined prior to manufacture.

SubclassCharacteristics(AFTETerminology): Features that may be produced

during manufacture that are consistent amongitems fabricated by the same

tool in the same approximate state of wear. These featuresare not

determined prior to manufacture and aremore restrictive than class

characteristics.

Identification (AFTETerminology): Agreement of all discernible class

characteristicsand sufficient agreement of a combination of individual

characteristicswhere the extent of agreement exceedsthat which can occur

in the comparison of toolmarksmade by different toolsand isconsistent with

the agreement demonstrated by toolmarks known to have been

produced by the same tool.

Exclusion / Elimination (AFTETerminology): Significant disagreement of

discernible classcharacteristicsand/or individual characteristics.

Blind Verification: The confirmation of an examiner'sconclusion by another

competent examiner who hasno expectation or knowledge of the prior

conclusion1. In some instances, thismay lead to an entire re-examination of

the case.

Return to Overview

Inconclusive ?A(AFTETerminology): Agreement of all discernible class

characteristicsand some agreement of individual characteristics, but

insufficient for an identification.

Inconclusive ?B(AFTETerminology): Agreement of all discernible class

characteristicswithout agreement or disagreement of individual

characteristicsdue to an absence, insufficiency, or lack of reproducibility.

Inconclusive ? C(AFTETerminology): Agreement of all discernibleclass

characteristicsand disagreement of individual characteristics, but insufficient

for an elimination.

Suitability for Comparison (Suitability Determination): Assessment of whether an item exhibitsclassand/or individual detail.

Field Strip: To disassemble a firearm for cleaning, repair, or transportation.

Detailed Strip: To disassemble a firearm beyond Field Strip.

Test Standards (TS): Known standardsproduced by/from a

tool/firearm/firearm parts. Can include test fired ammuniton components,

casts, forced/pushed bullets.

Inconclusive: Agreement of all discernibleclasscharacteristics. Insufficient

agreement and/or disagreement of individual characteristics. Cannot

identify or exclude.

*Abrief summary of selected terminology. For the purposesof thisdocument, the

AFTEdefinitions

2 are used for any termsotherwise not listed here.

1The Fingerprint Sourcebook. Washington, DC: U.S. Dept. of Justice, Office of Justice

Programs, National Institute of Justice, 2011.

2AFTEGlossary: https://afte.org/resources/afte-glossary

3 https://www.nist.gov/itl/sed/topic-areas/measurement-uncertainty

Capacity Test: Atest to determine the maximum number of cartridgesof

ammunition a magazine or a magazine and firearm are capable of holding.

Impact Test: Testingof a firearm in a controlled settingto determine if

discharge may occur asa result of being struck or striking a surface.

GRCDatabase: General RiflingCharacteristicsDatabase. Adatabase of

firearmsdetailing their general rifling characteristicsincluding, but not

limited to; caliber, rifling type, land and groove dimensions, and direction of

twist.

Trigger Pull Measurement (AFTETerminology): Measurement of the amount

of force which must be applied to the trigger of afirearm to cause sear

release. It ismeasured by hangingweightsor an instrument touchingthe

trigger at a point where the trigger finger would normally rest. Theforce

applied during measurement isapproximatelyparallel to the bore axis.

Trigger Puller : An instrument used to accurately measurethe trigger pull of

a firearm. Examplesinclude standard weights, springgauges, and mechanical/digital devices. Also known asa trigger tester.

Measurement: In some casesmeasurementsmay be taken by linear measurement device for length (e.g. Barrel Length), or may be assessed using

a tool to meeasure weight (e.g. Trigger Pull).

Measurement Uncertainty: Parameter, associated with the result of a measurement, that characterizesthe dispersion of the valuesthat could

reasonably be attributed to the measurand.3

AssessAction Type (adopted from AFTETerminology): Assessment of the

workingmechanism of a firearm. The combination of the receiver or frame,

the breech bolt, and the other partsof the mechanism by which a firearm is

loaded, fired, and unloaded. May be broken down into action such as

automatic, semiautomatic, bolt action, single action etc.

Ferrousv Non-Ferrous (adopted from AFTETerminology): Ferrous materials

are alloyscontaining a significant amount of iron. Ferrousmetalsare magnetic; versusnon-ferrousmaterialswhere the main component isnot

iron and isnot magnetic.

Safety Mechanisms (AFTETerminology): Adeviceon a firearm intended to

help provide protection against accidental dischargeunder normal usage when properly engaged.

Evidence TestingPlan (2500 series): Seriesof stepsplaced on the

appropriate pageswhere the user optsto either test additional evidence

itemsin a case or, in the event the examinationsare complete, to move on to

reportingsteps.

GRCDatabase Search (10000 series): General RiflingCharacteristics

Database path. Seriesof stepswhere the user optsto perform GRCdatabase

search during the course of the examination asappropriate, while allowing

them to then return and do additional examinations.

Abbreviations:

PAP: Per Agency Policy

ICD: Individual Characteristic Database