Shoeprints 1

Aim:  How do scientists analyze shoeprints? Shoeprint impressions are retained on surfaces in two- and three-dimensional forms. Almost all impressions, including partial impressions, have value for forensic comparisons. In this lesson, students learn how to analyze shoeprints. 

 

Objectives of the Lesson:

Students will be able to:
            2)
explain how shoeprints can be individualized. 

Motivation:  Have students examine the bottom of their own shoe and list and characteristics that they think are unique.  Do any students have the same exact shoes (brand and model) in class?  If so, what characteristics distinguish them?   

Content of the Lesson:
Show a PowerPoint presentation to review characteristics of  shoeprints that have probative value.
 
Distribute the Shoeprints Worksheet and have students identify the class characteristics (brand, size, tread pattern) and "accidentals" that can individualize the shoe (wear, tear, imperfections).
 
Optional: students make an ink print of the sole of their own shoe and identify accidentals that may be present.
 
Background:
“Shoeprints, sometimes inaccurately referred to as "footprint" are found at scenes of crimes with great regularity. For this reason they have long been studied by police and crime laboratory personnel. There is no doubt that a comparison of a shoe trace found at the scene of crime obtained from a defendant can be a valuable ink associating the defendant with a crime. The question that is more difficult to answer is whether a particular shoe trace can be positively identified as having been made by a specific item of footwear. Even though there is no recognized "science" of footwear comparisons, it has been widely accepted by law enforcement as well as by the courts that this kind of identifications can be made when adequate evidence is available. The science of footwear investigations is evolving now, since more research groups are working on shoeprints.

“Shoe prints may be found as either prints or impressions. Prints are two-dimensional, made by depositing or removing material from a hard surface. Impressions are three-dimensional and made in a pliable material. Both class and individual characteristics are present in each of the two types of trace evidence and are identifiable. A shoeprint is unique due to its many variables: length of wear, random marks and scratches and the design on a particular sole. For prints lifting with foil and photography is the major technique, and is often combined with casting for impressions.”   (From Shoeprint and Footprint Comparison, http://forensic.to/shoeprint.html )
 
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Steve Gallagher,
Aug 31, 2009, 8:52 AM
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