The document discusses footwear impression evidence, defined as physical objects retaining characteristics from contact, such as footprints and tire impressions. It highlights the role of footwear impressions in linking suspects to crime scenes, the challenges in collecting such evidence, and methods for capturing and analyzing the impressions, including casting and digital enhancement. Additionally, it covers the importance of proper handling and documentation to ensure the integrity of the evidence.

1. Footwear Impression
Evidence
Presented By
Priyanka Gadisetty

2. Impression Evidence
• Defined as – “objects of materials that have retained the
characteristics of other objects or materials through direct physical
contact”
• Fingerprints, palm prints, footwear impression, tire impressions, bite
marks, glove prints, footprints, socked foot impressions, firing pin
impressions, lip impressions, ear impressions
• Plant and animal fossils

3. Footwear impressions
• Found en route to, at, and exiting from the crime scene
• Link between the criminal and the place where the crime occurred
• Found in very small percentage of cases
• Difficult or inconvenient to find
a) Ground surfaces
b) Latent prints
c) Requirement of specialized lighting techniques
d) Little of no experience of investigator
e) Rush in searching crime scene
f) Limited knowledge of footwear impression examination

4. Footwear impressions
• Frequency of footwear impressions
• Durability of footwear impression
• Age of impressions
• Positive identification of footwear

5. Information Provided
• Type, make, description, and approximate or precise size of the
footwear that made them
• Process of developing a suspect
• Crime reconstruction
• Determining the number of suspects, their path into and through the
crime scene, their involvement in the crime, and the events that
occurred during the crime
• Corroborate or refute the information provided by witnesses or
suspects

6. Gait Characteristics

7. Formation of footwear impressions
• Creation of static charges – clean, dry shoes, taking several steps and
then walking across and stepping on a hard flat surface such as a tile
floor
• Deformation of the surface – soil, carpets, etc. – use of holography
• Transfer of a trace or residue materials – negative and positive images

11. Areas to check
• Actual point of occurrence of the crime
• Point of entry
• Path through the crime area
• Point of exit and other exterior areas
• Near other footwear impressions

12. Handling footwear impressions
• Take general crime scene
photographs – take
examination quality
photographs
• Make notes and crime
scene sketches
• Remove the impressioned
item from the scene
• Never cover an impression
with tape or plastic

13. Casting 3D footwear impressions
• Significant depth in addition to length and width
• Superior to photography
• Photography and casts must be used to supplement each other
• Possible loss of details in photographs
• Casting materials – silicones, moulage, paraffin wax, alginates, plaster
of paris, and dental stones
• Silicones – Expensive, too thick to flow in impression, take longer time
to cure
• Paraffin wax – 20 – 30 min to melt, more quantity is required

14. Qualities for a good casting material

16. 2D footwear impressions
• Electrostatic lifting:
It is a tool that electrostatically charges particles within dust or light
soil, which are then attracted and bonded to a lifting film. This method
is best for collecting dry or dusty residue impressions on almost any
surface, even the skin of a cadaver. Imprints and impressions may be
further processed to enhance or bring out additional minute details.
For example, a digital enhancement program such as Adobe
Photoshop® can be used to improve the quality of a photographed
impression. Fingerprint powders and chemical stains or dyes can
enhance image color or increase the contrast against the background.
This enables lifted or casted evidence to be photographed or scanned.

17. Latent footwear impressions
• Powders
• Footwears in blood