Imprint/Impressions exam 1

should be 40 questions

2 main functions of impression evidence 

Recovery process: discovery and preservation of prints 

Identification process: comparisons and findings and analysis 

Why are footprints overlooked 

Lack of training in proper searching and collection 

Evidence is undervalued/not understood 

T/F shoe print evidence is always left at a scene 

true

Deep footprints with the front pressed deeper than the rest of the print and a long stride indicates what

running 

If the prints are consistently deeper on one side, the person was likely doing what

carrying something 

the height of the wearer may be roughly estimated by measuring what

the stride length and shoe size 

4 basic methods of recording footwear impressions 

Photography 

Documenting/sketching 

Casting – 3D  

Lifting - 2D 

what characteristics for shoes belongs to a particular group and brand/size of shoe 

class characteristics

what characteristics for shoes belongs to a specific to a single person and their wear patterns, gait, embedded objects, cracks are specific

individual characteristics

3 types of individual characteristics

neutral pronation, over pronation, and under pronation or supination

which type of individual characteristic will have even wear on the front and rear 

Neutral pronation

which type of individual characteristic has the ankle turned in, toward the other foot 

Over pronation

which type of individual characteristic has the ankle is turned out, away from the other foot

Under pronation or supination

3 categories of footprints 

Visible prints

Plastic prints

Latent prints

what kind of impression results when a shoe sole accumulates and then deposits material that is transferred in the shape of the areas of the sole that contact the ground surface 

(Leaves tracks of where they walked)

positive impression

what kind of impressions are produced when the shoe sole removes residue (dust, blood) from a surface, leaving the residue where the areas of the sole did not come in contact with the substrate

(Leaves empty space/what's left behind in the space they stepped in)

negative impression

the tread design and dimensions of the tire are known as

tire impressions

the related dimensions of the 4+ wheels is known as the

tire tracks

2 types of tires

original equipment (OE) tires and replacement tires

which type of tire is sold on new cars, lots of cars have the same size/brand and can’t distinguish the car by these tires until worn down

original equipment tires

which type of tire is purchased to replace old, worn tires 

replacement tires

4 design elements of tires

grooves: around a tire 

sipe: small grooves 

slots: across a tire 

tread wear indicator: raised bar under design that shows after wear

what does the tread wear indicator do in a tire

it is a raised bar under the design, it shows after wear

T/F the entire tire track should be photographed with overlapping photos and a ruler bc tracks are variable along its length 

true

when collecting photo evidence of impressions, you need to have what

Photos with log of location, time, date, etc. 

T/F typically we find a shoe print, not their bare feet print

true

footprint evidence is always left at a scene, but useable footprints are found at about what percentage of scenes 

40%

how are visible prints seen

Stepping in paint/blood 

how are plastic prints seen

Mud, snow, sand, 3D impression 

how are latent prints seen

using lights/chemicals, 2D impression 

4 reasons why you may not find footprints

Incomplete searches of the crime scene 

Weather conditions 

The impression has been intentionally destroyed 

Not believing impressions could be there after people have walked all over the scene 

class characteristics can narrow down the type of shoe by its

size, style, tread pattern

individual characteristics can narrow down whose shoe it is by its

cuts, cracks, embedded objects, and wear patterns

Smaller footprints that are slightly pigeon-toed (pointing inward) likely belong to

a woman

T/F men tend to walk with their toes straight or outward

true

foot length is about what percentage of a person’s height

25%

2 commercial databases that help identify the types of shoes found at a crime scene

treadmark and solemate

which commercial database uses four parameters to help identify outside sole impressions to ease time-consuming recovery

treadmark

which commercial database holds manufacturer information and several pictorial images to help determine the type of shoe the print belongs to

solemate

footwear impressions are used at what kind of evidence

exculpatory evidence