Footwear Evidence

1. Footwear Evidence

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

3. 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.

4. 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.

5. 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

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 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

8. 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--a defense by an accused person purporting to show that he or she could not have committed the crime in question; . • to prove (a person) to be in error. • Gait or Tracking information?

10. 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. 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. 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. 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. 3-D impression should be cast • Cast picks up detail; is durable • Cast after photo • Use dental stone

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

18. 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.