Analysis of shoe mark

The Physical Sciences Section provides a wide range of service to government departments in the areas of physical examination including traffic accident reconstruction, tyre examination, vehicle number restoration, forgery and counterfeit items and cases involving toolmarks and shoeprints.

Traffic accident reconstruction

Traffic accident reconstruction (TAR) involves the application of various scientific disciplines including mathematics, physics, automotive engineering and scene investigation techniques in deciphering possible cause of road traffic accidents. The forensic examination of failed tyres often provides useful information in determining whether their deflation causes the accident or is a result of the impact in the accident. Vehicle number examination and restoration entails, as the name suggests, the discovery and retrieval of numbers unique to the vehicles concerned as a means of detecting unauthorised vehicle-taking or modification. Forgery and counterfeit items such as precious metals, gems and Hong Kong circulation coins are investigated using state-of-art instruments. The section also deals with a large number of theft-related cases involving the preservation or matching of toolmark and/or shoeprint exhibits.

	X-ray fluorescence spectrophotometer

The following instruments are used routinely by the Section:

• Comparison microscope
• X-ray fluorescence spectrophotometer