1. Footwear Evidence

2. Objectives:  What is footwear evidence?  How is it involved in crime scenes?  How is it collected?  How is it analyzed?

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

4. Three different types of shoe prints: 1. 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. Footwear Evidence

5. 2. 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. Three different types of shoe prints: Footwear Evidence

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

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

8. 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 Footwear Evidence

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

10. Recovery of Footwear evidence  All shoeprints should be recovered from the scene as soon as possible (Transient evidence).  Scene should be controlled to prevent destruction of evidence. Footwear Evidence > Collection

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 Footwear Evidence > Collection

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 Footwear Evidence > Collection

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 Footwear Evidence > Collection

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

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

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

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

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. Footwear Evidence > Analysis

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