Physical methods
The examination of items such as clothing for glass particles in order to establish a link to a crime scene.
Glass evidence
Analysis of glass is used to aid criminal investigations. Normally, this is a comparison between recovered fragments of glass, which are typically very small, against a sample of glass recovered from the scene of a crime.
Glass fragments alongside the point of a pin
Marks left at scenes
Marks of various kinds left at scenes, including those made by tools, footwear, tyres, etc are visualised and compared against “suspect” tools or footwear.
Footwear marks are captured and enhanced using specialist lighting and photography prior to comparison with reference items.
A footwear impression photographed using oblique white light
Marks suspected to have been made by tools are examined microscopically.
Other types of examinations involve physical fits of items to prove a single source such as fragments from a vehicle left at a scene, eg headlamp glass, bumper fragments with a reference vehicle.