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Guide for the Examination of Footwear and Tire 

Impression Evidence (03/2006)

1. Scope

1.1 This Guide provides procedures for the examination of footwear and tire 

impression evidence in the laboratory.

1.2 The particular procedures and methods employed in a given case will depend on 

the evidence.

1.3 This Guide may not cover all aspects of unusual or uncommon conditions.

1.4 This Guide does not purport to address all of the safety concerns, if any, 

associated with its use. It is the responsibility of the user of this Guide to establish 

appropriate safety and health practices and determine the applicability of regulatory 

limitations prior to use.

1.5 This Guide is not intended as a substitute for training in the forensic examination 

of footwear and tire track evidence. Completion of a training program and 

experience in these skills is essential to understanding and applying the principles 

outlined in this Guide.

1.6 This Guide relates to the examination of footwear and tire impressions after they 

are documented and collected in the field.

2. Terminology

Refer to the Standard for Terminology Used for Forensic Footwear and Tire 

Impression Evidence for a definition of terms used in this document.

3. Significance and Use

3.1 The procedures outlined here are grounded in the generally accepted body of 

knowledge and experience in the examination of footwear and tire impression 

evidence. By following these procedures, a forensic footwear and tire tread examiner 

can reliably reach an opinion regarding the source of an impression.

3.2 Footwear and tire tread impressions are examined for the purpose of aiding 

forensic investigations
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Guide for the Examination of Footwear and Tire Impression Evidence (03/2006)

4. Interferences

4.1 Footwear and tire impression evidence may have inherent limitations that can 

interfere with the procedures in this Guide. Limitations, when known, should be 

noted and recorded.

4.2 Limitations can be due to substrate features, quality and quantity of original 

impressions and methods of collection.

5. Equipment and Requirements

5.1 Appropriate light source(s) of sufficient intensity to allow fine detail to be 

distinguished

5.2 Magnification

5.3 Finely divided scale

5.4 Imaging or other equipment for recording observations as required

5.5 Sufficient time and facilities to complete all applicable procedures

5.6 Chemicals, materials, and equipment necessary for documenting, reproducing, 

and/or enhancing

5.7 Materials necessary for collection of test impressions

5.8 Reference and resource materials

5.9 Equipment, process, and methodology for recording/saving results in the case 

files

6. Procedures

6.1 All procedures shall be performed when applicable and noted when appropriate. 

These procedures need not be performed in the given order.

6.2 Examinations, relevant observations, and results should be documented. The 

examination notes must include a complete record of observations to support 

conclusions reached. These notes should include, but are not limited to, the 

following:

6.2.1 Initial description, condition of evidence, and packaging

6.2.2 Photographs, images or diagrams of evidence as appropriate

6.2.3 Relevant observations of similarities or differences
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Guide for the Examination of Footwear and Tire Impression Evidence (03/2006)

Note: At various points in these procedures, if differences in class characteristics 

are present or if an impression is lacking in quality or comparability, then the 

examiner may discontinue or limit the procedure(s). The reasons for such a

decision shall be documented and reported accordingly.

6.3 Record and document the initial condition of the submitted evidence

6.3.1 Determine if all original impression evidence has been submitted.

6.4 Preparation of Evidence

6.4.1 Questioned evidence may require initial preparation prior to the 

examination process. This preparation may include cleaning casts, recognition 

and preservation of other relevant physical evidence, photographic 

documentation, and printing of photographic images.

6.4.2 Known shoes and tires require documentation of condition, brand, and 

general design features.

6.4.3 Assign identifiers to each item of evidence.

6.5 Evaluate the questioned impression evidence for the following:

6.5.1 Quality, clarity, and comparative potential

6.5.2 Enhancement potential

6.5.3 Presence or absence of class characteristics

6.5.3.1 If no class characteristics are present discontinue these procedures 

and report accordingly.

6.6 Processing and enhancement of impressions

6.6.1 Refer to the Guide for the Detection of Footwear and Tire Impressions in 

the Laboratory.

6.6.2 Document and photograph all procedures utilized.

6.7 Comparison with known footwear or tires

6.7.1 Visual comparison of design

6.7.1.1 If design is different, document, discontinue these procedures and 

report accordingly.

6.7.1.2 If design is similar, prepare test impressions and continue with these 

procedures.
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Guide for the Examination of Footwear and Tire Impression Evidence (03/2006)

Note: Refer to the Guide for the Preparation of Test Impressions from 

Footwear and Tires.

6.7.2 Specific design and physical size and shape of design

6.7.2.1 If specific design and/or physical size and shape of design, to include 

noise treatment (pitch sequence) of tires, are different, document, discontinue 

these procedures and report accordingly.

Note: If physical size is different, consider scaling, perspective and other 

issues.

6.7.2.2 If specific design and physical size and shape of design correspond, 

continue with procedure.

6.7.3 Wear

6.7.3.1 If the position and degree of general wear are different, document, 

and evaluate possible wear changes between date of crime and date shoes 

or tires were recovered.

6.7.3.2 If the position and degree of general wear corresponds, continue with 

procedure.

6.7.4 Individual characteristics

6.7.4.1 Individual characteristics should be evaluated according to their 

position, size, shape, orientation and clarity. When sufficient individual 

characteristics are present in the questioned impression and correspond with 

respective features in the known shoe or tire, an identification can be effected. 

Evaluate, document and report accordingly.

Note: Due to varying circumstances, not all individual characteristics will 

reproduce in every impression. Therefore the absence of an individual 

characteristic is not a basis for elimination and does not preclude 

identification.

6.8 Information regarding the possible make/model and/or manufacturing source of 

the shoe or tire that made the questioned impression may be determined using 

reference materials/sources. Manufacturing, production, distribution and sizing 

information may also be determined with assistance from the specific manufacturers. 

This information may be useful for investigative purposes.

7. Report

7.1 Examinations conducted, procedures utilized, evidence photographed, and 

conclusions reached should be documented and may also appear in a report.
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Guide for the Examination of Footwear and Tire Impression Evidence (03/2006)

8. Bibliography

Bodziak, W. J., Footwear Impression Evidence, 2nd ed.; CRC Press: Boca Raton, 

FL, 2000.

Cassidy, M. J., Footwear Identification; Public Relations Branch of the Royal 

Canadian Mounted Police: 1980. (Reprinted by Lightning Powder Company, Inc. 

1995.)

IAI Recommended Course of Study for Footwear & Tire Track Examiners, 

International Association for Identification: Mendota Heights, MN, 1995.

McDonald, P., Tire Imprint Evidence, CRC Press: Boca Raton, FL, 1992.

Nause, L., Forensic Tire Impression Identification, Canadian Police Research 

Centre: Ottawa, ON, Canada, 2001.