Chapter 19

  1. Created this CLT, ECU graduate, found shoe impression in OJ simpson case

    Bill Bosiak
  2. •During everyday walking, persons leave both _______ and ________ two dimensional shoe print impressions on areaswhere they travel.
    •If on soft material such as soil, snow or sand they leave a ________ _________ ________.
    three dimensional impression
  3. •Those remain after a shoe has permanently deformed surface
    •Some impressions may be shallow and others deep
    •The quality of the image can have great detail to have little or no value depending on the soil composition, moisture, or contaminants
    Three Dimensional Impressions
  4. •Those made on non-giving surfaces such as tile, linoleum, wood flooring and also including paper, plastics, doors, carpeting, broken glass, etc.
    •Very often the less visible impressions actually contains greater detail than impressions made in heavy grease, blood, etc.
    •The lighter the footprint, the better the impression
    Two Dimensional Impressions
  5. •Identification of footwear
    •Base on the agreement of both class and individual characteristics
    Information from Footwear Impressions
  6. •Elimination of footwear
    •Based on differences of class characteristics
    •Useful for accounting for all footwear impressions left at a scene
    •Changes in or the absence of random individual characteristics are normally not used to eliminate a shoe
    •ex: wear patterns
    Information from Footwear Impressions
  7. •Partcipation in the crime
    •Impressions found at the scene and identified to persons with no legal reason to be at the scene
    • Examples inclue: impressions on broken glass inside a forced entry point
    Information from Footwear Impressions
  8. •Location of impressions
    •At the point of entry and exit (especially; destroy suspects impression alot of time from police, emt, etc. coming in)
    •Other locations in the scene may provide information to the location of physical evidence
    Information from Footwear Impressions
  9. •Rebuttal or confirmation of suspect's alibis
    •Location and documentation of impressions may help to prove whether the suspect is lying or telling the truth
    Information from Footwear Impressions
  10. •May be determined through footwear databases or other means
    •FBI maintains a footwear database
    Determenation of shoe brand
  11. •Recovery of the same footwear impressions from the different crime scenes
    Linking scenes of crimes
  12. •If the manufacturer of the shoe is known, an accurate determination of the shoe sixe that made a full or partial impression is possible
    Determination of shoe size
  13. •Locating more than one suspect shoe design
    -Determine whether it is a suspects shoe or not
    Number of perpetrators
  14. •Backtracking of footwear impressions can assist in located items of evidence
    •Can assist in associating footwear impressions with tire impressions
    ex: person getting into car after committing a crime
    Association with other evidence
  15. •Use primarily for medical evaluation of persons with walking problems
    •Measurements of a person's stride, step length, and step with change as they change speed or over different surfaces
    •Cannot be reliably used as a means of personal identification
    -Although running will mess this up
    Gait Characteristics
  16. •Following the path of an individual by observing evidence that person has created as they pass over various surfaces
    -usually doesn't take long
    - better when using dogs
    Tracking Footwear Impressions
  17. •Success in locating footwear impressions and recovering the maximum detail has direct impact on the usefulness of the evidence and the subsequent examination
    Location and Recovery of Footwear Impressions
  18. •In most cases, shoe impressions are by far partial
    •Even small partial impressions may contain enough detail to be identified or eliminated as having been made by particular shoe
    Full vs. Partial Impressions
  19. •Slow visiual search (done away with quickly)
    •High intensity oblique lighting
    •Electrostatic lifting
    Searching for Impressions
  20. •Using high voltage device to electrostatically transfer a dry orgin dust or residue impression to a black film

    -Lay metal foil over footprint, one side black
    -Never use it on a surface that is wet
    - re-chargeable units, not plugged in
    Electrostatic Lifting
  21. •Notes about location and direction of impressions
    •Photographs of both the impressions and of the location of the impressions
    -direction traveling very important
  22. •Any impressions that can be safely recovered should be taken to the laboratory including paper, glass, etc.
    -dont try to do this stuff on a crime scene
    Submittal to a Laboratory
  23. •Must be photographed with examination quality photography
    •Only one purpose: later examination with the suspected footwear
    •Photos must be taken from directly over the impressions (other ways would distort it)
    •Camera format must be 35mm(size of negative) or larger and capable of manual focus
    •Most digital cameras fo not, at this time, have a high enough resolution
    Impressions That Cannot Be Removed from the Crime Scene
  24. Illustrates the scene (pictures of a crime scene)
    Illustrative Evidence
  25. Turns out to be the impression you use
    Substitutive Evidence
  26. •Scale must be placed in each photograph with the scale being the same depth as the impression
    •Camera must be placed on a tripod
    •Impression and scale must fill the entire frame
    •Camera should be focused on the bottom of the impression, not the scale
    •Oblique lighting should be used from at least three sides (more is better)

    *Scale goes OUTSIDE of the impression
    -in at the same depth
    • Impressions that Cannot be removed from the Crime Scene
Card Set
Chapter 19
Forensic Science