Footwear and Bloodstain Evidence Flashcards
(57 cards)
What is footwear referred to as?
“forgotten evidence” often overlooked.
what might footwear evidence provide?
- type and make of shoe
- approximate size,
- number of suspects,
- pathway in,
- possible sequence of events in crime scene
Why is footwear evidence overlooked?
- lack of training in proper search techniques, photography, and preservation of evidence
- value of this evidence is not understood
- lack of education in the comparison of footwear and report writing
What impressions were found at the Lloyd homicide investigation?
- footwear impressions from both Williams and Lloyd
- tire track impressions
how did the impressions found at the scene aid in Williams arrest (Lloyd homicide)?
- Williams went through a police checkpoint driving that make of vehicle
- he was wearing the same boots he wore at the scene
What was the key piece of evidence in the OJ Simpson case?
his Bruno Magli shoes that were found at the case
why did OJ’s shoes give him away?
he lied about having the Bruno Magli shoes but was clearly documented to own a pair in multiple images
Where must a scale be placed in a shoe impression?
on plane with bottom of the impression
How do you take impression photos?
oblique lighting must be used to make shadows showing depth
What are class characteristics?give an example.
manufactured characteristics where they are intentional or unavoidable characteristics repeating through process
- ie. logos and patterns
What are accidental characteristics? give an example.
random characteristics that are dependent on chance.
- ie. evidence shoes being worn like nicks or damage
explain the process of a gelatin lifter. what is it for?
- sheet of rubber with low adhesive gelatin layer that can lift prints from almost any surface
- used with fingerprint powders on 2D surfaces
- for footwear impressions or fingerprints
explain the process of a electrostatic lifter. what is it for?
- charging a plastic film placed over dust print creating electrostatic adhesions and draws the film onto the surface
- for footwear impressions or fingerprints
explain the process of casting. what is it for?
- dental stone or other setting liquid placed on a print
- used for recording 3D footwear impressions found in snow, sand, or soil.
where are 3D impressions typically found?
outside bc dirt
Where should the camera be relative to the impression?
on plane with the impression and the scale should be level with the bottom of the impression
what depth of field should be used for 3D impressions?
high depth of field (F18-F22)
What should also be included in impression photography?
an identifier usually number data (case number, date etc.) and initials.
what can be used to enhance impressions usually in snow?
coating the print with snow wax to give contrast
What do you include in notes on footwear?
- where found
- direction of travel
- detail in impression
- substrate
- how preserved (photos, casting)
- development enhancement technique
- how many
- how many different types
- any footwear for elimination from witnesses, victims, or suspects
If a shoe is taken from a suspect 6 months after a crime what might happen?
accidental patterns many emerge due to wearing
how might you compare an impression to the hypothesized match?
superimposing it over the real print with clear acetate copy
What is Leucocrystal Violet? when is it used in relation to other enhancement techniques?
visualized blood turning deep purple in contact with blood
- used after luminol
What is the purpose of Blood pattern analysis?
drawing conclusions about the nature, timing and other details of the crime
