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Footwear Evidence

Footwear Evidence. Summary. What is footwear evidence? How is it involved in crime scenes? How is it collected? How is it analyzed?. Footwear Evidence. What is footwear evidence?. Different shoes will leave behind prints of different sizes and patterns. . Footwear Evidence.

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Footwear Evidence

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  1. Footwear Evidence

  2. Summary • What is footwear evidence? • How is it involved in crime scenes? • How is it collected? • How is it analyzed?

  3. Footwear Evidence What is footwear evidence? Different shoes will leave behind prints of different sizes and patterns.

  4. Footwear Evidence Three different types of shoe prints: • Three dimensional impression • Shoeprint made in soft material (dirt, snow) • Requires making a cast of the print • Composition of dirt or snow will determine the detail of the impression.

  5. Footwear Evidence Three different types of shoe prints: • Two dimensional print (visible) • Dirt or other material picked up by shoe and deposited onto flat, hard surface. • Variety of surfaces and materials deposited makes recovery of these prints complex.

  6. Footwear Evidence Three different types of shoe prints: • Two dimensional print (latent) • Can leave behind barely visible dust • Can leave impression in polish/wax/dust

  7. Footwear Evidence Three different types of shoe prints: • Two dimensional print (latent) • Can leave behind barely visible dust • Can leave impression in polish/wax/dust

  8. Footwear Evidence How are shoe prints evidence? • Most suspects wear shoes. • Footprints are always left, it is whether they can be located and differentiated from other prints. Burglar Shoes

  9. Footwear Evidence What information can shoe prints provide? • Link suspect or victim to scenes • Link two crime scenes Location of prints can: • Lead to more evidence • Refute alibis • Gait or Tracking information?

  10. Footwear Evidence > Collection Recovery of Footwear evidence • Due to numerous nuances, all shoeprints should be recovered from the scene. • Scene should be controlled to prevent destruction of evidence.

  11. Footwear Evidence > Collection Recovery of Footwear evidence • Some prints can be visualized by darkening a room and using a bright light at a low angle. • Footprints should be documented: Location recorded and photographed

  12. Footwear Evidence > Collection Recovery of Footwear evidence • Objects with footprints should be removed if possible (paper, glass) • If can’t be removed, an examination quality photo should be taken. Ruler: allows for enlargement to real size

  13. Footwear Evidence > Collection After photo, 2-D print can be lifted: Electrostatic Lifting: • A charge is used to lift dry materials from surface to black film. • Lift provides more contrast • Non-destructive • Photographed for evidence

  14. Footwear Evidence > Collection After photo, 2-D print can be lifted: Dusting: • Fingerprint powder can visualize print • Lifted with adhesive or gelatin • Photographed for evidence

  15. Footwear Evidence > Collection 3-D impression can be highlighted Spraying with colored wax spray

  16. Footwear Evidence > Collection 3-D impression should be cast • Cast picks up detail; is durable • Cast after photo • Use dental stone

  17. Footwear Evidence > Collection Enhancement Methods If footprint is made of blood, TMB or other color changing reagents can help visualize.

  18. Footwear Evidence > Analysis Analysis of Footwear Evidence: Class Characteristics can be used to eliminate a suspected shoe or suggest a shoe could have made the impression. • Size • Pattern Suspect shoe or test impressions compared.

  19. Footwear Evidence > Analysis • Individual Characteristics can be used to identify an exact shoe. Analysis of Footwear Evidence: • However, these can change over time.

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