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Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd Edition*Forensic ScienceAn Introduction to Scientific and Investigative Techniques

Stuart H. James and Jon J. Nordby

CRC Press: Forensic Science, James and Nordby, 3rd Edition

*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionChapter 19Forensic Footwear Evidence

Chapter Author: William J. Bodziak

Presentation created by Greg Galardi, Peru, NebraskaEdited by Stuart H. James, Fort Lauderdale, Florida andDan Mabel, Richmond, Virginia


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionForensic Footwear Evidence

Physical contact between footwear and a viable surface leaves a transfer of class and individual characteristics, which can be used in identification of possible suspects


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionForensic Footwear EvidenceSteps of footwear evidence collection:Detection and recovery of footwear evidence from scene of crimeEnhancing evidence as necessaryProducing known impressions of shoes being examinedComparing crime scene impression with footwear


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionForms of Footwear ImpressionsThree Dimensional Impressions impression remaining after a shoe permanently deforms a surface- found in sand, mud, snowTwo Dimensional impressions those impressions made on tile linoleum, wood flooring etc. Some are highly visible and others are latent


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionInformation from Footwear ImpressionsThe following information may be obtained from footwear impressions:Identification of Footwear Elimination of Footwear Participation of suspect in crimeLocation of ImpressionsRebuttal or confirmation of alibisDetermination of shoe brand FBI Laboratory


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionInformation from Footwear Impressions

Linking of Suspects to the Crime SceneDetermination of Shoe SizeNumber of perpetratorsAssociation with Other EvidenceGait CharacteristicsTracking


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionLocation and Recovery of Footwear ImpressionsIt is critical that proper techniques be used to locate, document and recover footwear evidenceFull and partial impressions must be recoveredScene should be secured and evidence collected


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionLocation and Recovery of Footwear ImpressionsElectrostatic Lifting aggressive technique to recover impression, normally on tile, wood, etcPlacards or markers used to document locations of impressionsIf possible, remove and transport impressions


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionLocation and Recovery of Footwear ImpressionsQuality photographs should be taken of impressions if they can not be transportedPhotographs are taken for later comparison with suspected footwear, therefore they must be very clearScale should be used to gauge size of footprint


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionTwo Dimensional ImpressionsOnce an impression has been photographed, the print may be able to be liftedElectrostatic lifting transfers Fingerprint powder in combination with mikrosil may be used on impressions where electrostatic lifting does not work


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionThree Dimensional ImpressionsDental stone is primary method of casting footwear impressionsOn wet surfaces, a spray wax may have to be used first to seal impressionMix dental stone with water in a ziplock bag for 3 minutesStone hardens in 20 minutesIn 24-48 hours it will have fully hardened


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionEnhancement MethodsPoor impressions may have to be enhanced by one of the following means:Forensic Photography oblique, ultraviolet, infrared or other special methodsPhysical Methods latent powder, lifting impressions, or impressions on paper


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionEnhancement MethodsChemical Methods reagents such as leuco crystal violet, amido 10 black, luminol or fuschin acid may be used

Digital Methods Software such as Adobe Photoshop can be used to enhance impressions


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionKnown Shoes and Preparation of ExemplarsFootwear from Suspected Persons:

All footwear a suspect owns should be seized for comparison

Shoes are needed to make test impressions


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionKnown Shoes and Preparation of Exemplars

Elimination Footwear Footwear worn by police officers, medical personnel should be accounted for when considering impressions left at scene


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionKnown Shoes and Preparation of ExemplarsKnown Test Impressions of Footwear

Examiner will make impressions of known footwear and compare them with suspected footwear impression to insure matching samples are highly detailed, and have individual characteristics of shoes


*Chapter 19CRC Press: Forensic Science, James and Nordby, 3rd EditionThe Examination Process and ConclusionsAreas of footwear which are examined by analyst include:Design of shoePhysical Size and Shape Wear marksIndividual Identifying Characteristics- cuts tar, gum etc


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