Exam 2 Flashcards
Impression
When one object makes physical contact with another, a physical characteristic is left on the recipient.
Print on soft or pliable surface
Leaves a 3-dimensional impression.
Print on hard surface
Leave a 2-dimensional impressions
Impression recipient
Made of a material that can form and hold a negative image of the donor markings
Examples of an impression recipiet
Soft plastics, soil, putty, paint, dust, metals, plastics, wood
Impression donor
Object that leaves behind a marking
Examples of impression donors
Shoe sole/heel, tire treads, fingerprints, footprints, lip prints, tools, metal dies, ribbing, fabric texture
Unique characteristics
Factor that determines if one object can be associated with another
Goal of serial number restoration
Restore an obliterated number on an object so the number can be used to identify that particular object
Can all impression evidence lead to individualization?
No
Impressed markings
Made by a downward perpendicular direction
Examples of impressed markings
Footprint, firing pin
Striated markings
Side to side parallel force
Example of striated markings
Gun barrel streaks, car paint transfer streaks
Reasons footwear evidence is overlooked
Nearly invisible, uneven ground, tampered with, misunderstood/undervalued