Forensics Impressions
What is a skid mark?
A tire mark on the road that is made when the tires are locked
What are some tools used in crimes?
Bolt cutters, screw drivers, knives, crowbars
Where are some places tool marks might be found?
Bones, locks, doors, frames
What else can differentiate teeth?
Chips, fillings, crowns and caps
Is a shoe print an individual or class characteristic?
Class
What needs to be analyzed on a tool mark?
Dimensions of the impression, ridges or striation patters, defects, and paint or metal shards left on the tool.
What can a footprint tell us about a crime?
Direction of approach, point of entry, sequence of events, gender and height of perpetrator
A bite mark and suspect would have both of these characteristics in common:
Distance from cuspid to cuspid, shape of mouth arch, unaligned teeth, teeth width and thickness, spacing, missing teeth, curves of biting edges, unique dentistry, wear patterns: chips/grinding
What is forensic odontology?
Forensic medicine that deals with dental evidence
The rhythm of your walk
Gait
What can footprints say about how a person walks?
Gait patterns(rhythm), walking style, stride, height, stance, pigeon toed or slew footed
What are two ways tool mark impressions can be classified?
Impressions and scratches
3 types of impression evidence
Imprints, indentations, striations
Why is it important to take photos of the tire tracks?
It is transient evidence and will only temporarily be there
Generally, a taller person will have a _____________ shoe size.
Larger
How can you tell if someone is running?
Long strides, deep prints, deep toes
What is a plastic footprint?
Making an indentation in a substance like mud or snow
What is a mold?
Negative replica of the impression made by the object
Where can bite marks be found at a crime scene?
On the victim, on food, on the perpetrator, on wood
How can you tell if someone if limping?
One foot is deeper than the other
Is an imprint plastic or patent?
Patent
What are the 3 types of footprints?
Patent, plastic, latent
What is needed for a footprint to help convict a suspect?
Photo or casting evidence of footprint, actual shoe of suspect, and expert witness to testify they are a match.
Is an indentation plastic or patent?
Plastic
What is a cast?
Positive replica of the object making the impression
How can you tell if someone is carrying something heavy?
Prints deep, shot steps, wide base, scuffing, shuffling
What can your shoe prints tell you?
Range of height, walking style, standing or running, point of entrance/exit, path to the weapon, linkage
How can you tell if someone is walking backwards?
Short irregular stride, deep toes, dirt displacement in direction
The ________________ of a tool are considered class evidence.
Size and Shape
Generally, a shorter person will have a ____________ shoe size.
Smaller
How can tools be used in a crime?
Stabbing or hitting someone or breaking into things.
Your step length
Stride
Why should we look at back tire tracks instead of front ones?
The backs run over the fronts and the fronts narrow when turning
What can an odontologist discover?
The identity of the victim or the perpetrator
What causes tool marks?
The use of the tool against a softer object
What evidence is there from tire tracks?
Track width, wheelbase, turning diameter
What is a patent shoe print?
Tracking a substance like paint or blood
What is a latent shoe print?
Transferring layers of thin grime to hard surfaces; invisible to the naked eye
How can a tire track impression be individualized?
Wear marks, nails, patching, and gravel
How can shoe prints be matched to an individual shoe?
Wear patterns, cuts, nicks, scratches, gouges, stones
What are indentations?
When an object pushes into material that is softer than the object;3-D
What are imprints?
When material from one area is transferred to another;2-D
How can you tell if the footprints are a man's or woman's?
Women have smaller feet and are pigeon toed. Men have large feet and are slew footed
______________ parts of a tool are considered individualized evidence.
Worn or damaged
Are people's teeth helpful in identifying a human?
Yes! Teeth will stay intact and the DNA is preserved will in the pulp of the tooth