Tire Tread Forensic identification through tire treads
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Forensic Tire Trad and Tire Track Evidence
Tire Tread Impressions: reflect the trad design and dimensional features of the individual tires
on a vehicle.
Tire Tracks: reflect general information about the vehicle that left the impression.
Bias Belted Tires: have plies running beneath the tread at an angle(bias) across the tire but with
the addition of belts beneath the tread surface.
Radial Tires: Plies run straight across the tire from bead to bead.
Green Tire: Tire that contains no tread design or sidewall information
Transverse Grooves/Slots: grooves that run across a tread.
2 sides of a Tire
Outer Sidewall: [label side], intended to face outwards.
Inner Sidewall: [serial side], includes tire brand,style,side, DOT number, Mold numbers.
DOT number: begins with DOT, 2 letters, plant code, location, week/yr made [DOT APB3 8BXX 3704]
Retread Tires: Tire carcass that has tread added to produce a useable tire
Mold cure rubber strips utilized and tire place into mold where tread design is molded into
Precure process utilizes tread rubber already containing tread design with a bonding system.
Lower quantities of Retread tires can help pinpoint suspects.
P 195/65 R 15 =
P Passenger tire
195 apx section with width in mm
65 aspect ratio [ration of height to width]
R Radial Tire
15 Rim diameter in inches
Noise Treatment: Arrangement of design elements of various sizes around the tire to reduce noise.
Helps examiner to find the exact location on a suspected tire or tires of the same design and
general tread dimension that made the crime scene impression.
Tread Wear Indicator: raised rubber bar above base of tire grooves, to indicate when the tire should be
Position of wear indicator, combined with position of noise treatment can offer valuable info
Tire Track Evidence:
Tire track width[stance] measurement from center of one wheel to the opposite wheel