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Locating an Area on a Suspect Tire for Comparative Examination to a Questioned Track

NCJ Number
113373
Journal
Journal of Forensic Identification Volume: 38 Issue: 4 Dated: (July-August 1988) Pages: 143-151
Author(s)
E D Hamm
Date Published
1988
Length
9 pages
Annotation
Tire track examiners should use all the tire class characteristics (noise treatment features, tread-wear indicator bars, and sidewall markings) available in the questioned tire track and the suspect tires to assist in determining which tire could have or did make a questioned track.
Abstract
Although some modern tires use computer-developed designs that can individualize tire areas with the noise treatment features, many designs use the noise treatment technique in the form of staggered tread blocks, such that design features are repeated in other areas of the tire. The examiner must locate every area of a tire that conforms to the design present in the questioned track and subject all of them to the same comparative examination. Tread-wear indicator bars are slightly raised areas at the bottom of the groove that run laterally across the tire tread to indicate when the tread has been worn to the extent that the tire should be replaced. In cases of excessive wear, the tread wear indicators will show as continuous bars across the tread design in both two-dimensional and depressed tracks. These can be valuable aids in locating an area for comparison. Tire sidewall markings will appear in depressed tracks and can be helpful in locating other tire class characteristics on a suspect tire. 1 table, 7 figures, 4 references.