SWGTREAD
Definition
Scientific Working Group for Shoeprint and Tire Tread Evidence; US body that developed the dominant guidelines for footwear and tyre-mark examination, class-subclass-individual hierarchy, and reporting standards.
- Organization type
- Scientific working group (US-based)
- Primary focus
- Shoeprint and tire tread evidence examination
- Key framework
- Class-subclass-individual hierarchy for impression comparison
- Current status
- Superseded by OSAC standards
Common questions
What is SWGTREAD and what does it do?+
SWGTREAD is the Scientific Working Group for Shoeprint and Tire Tread Evidence, a US-based body. It developed the standard guidelines and reporting practices for examining footwear impressions and tire marks found at crime scenes. The group created a framework that classifies characteristics into class, subclass, and individual levels.
What framework does SWGTREAD use for comparing tire impressions?+
SWGTREAD published a comparison framework that breaks tire impressions into three levels: class characteristics (general tire type), subclass characteristics (more specific tire features), and individual characteristics (unique marks and damage). This framework helps forensic examiners determine whether impressions could have come from the same tire.
Is SWGTREAD still the main standard for tire and footwear evidence?+
SWGTREAD standards were influential and dominant for many years, but they have now been superseded by OSAC standards (Organization of Scientific Area Committees). Examiners today refer to the newer OSAC guidelines for current best practices in tire and footprint examination.
Related terms
- Treadmate
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- Class Characteristics (Footwear)
- The manufactured outsole design features shared by all examples of a specific shoe model: tread pattern, size, shape, and logo placement.
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- Dental Stone
- A gypsum-based casting material harder and finer than plaster of Paris. Preferred for forensic 3-D casts because it captures detail at the...
- ESLA (Electrostatic Dust-Print Lifter)
- A device that applies a high-voltage static field to a metallised film, attracting dust particles from a footwear impression on a hard...
- EUCAP
- European Collection of Automotive Paints, maintained at the Bundeskriminalamt (BKA) in Wiesbaden; the European counterpart to PDQ for automotive hit-and-run paint comparison.
- FCIN
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- Hot Filament Failure
- Fracture of a tungsten bulb filament while at operational temperature (2,500-3,000 K); characterised by ductile deformation at the break, coiling, and tungsten...
- LA-ICP-MS
- Laser ablation inductively coupled plasma mass spectrometry; a technique that fires a laser pulse at a sample surface, vaporises a tiny amount,...
- PDQ (Paint Data Query)
- RCMP-maintained international automotive paint database. Stores binder, pigment and layer data for vehicle original-equipment finishes from major manufacturers. Used to narrow a...
Explained in these topics
- Impression Evidence: Footprints, Tyre Marks and CastingScientific Working Group for Shoeprint and Tire Tread Evidence; US body that developed the dominant guidelines for footwear and tyre-mark examination, class-su...
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