Today there is general recognition that trace evidence (fibres/fluids/particles) found at a scene of crime (SOC) can be instrumental in providing criminal intelligence to police investigations. Soil particles readily adhere to, and transfer from, clothing/shoes/vehicles/tools, and can therefore be treated as trace evidence, potentially linking or eliminating suspects to/from a crime scene.

The use of soil in criminal investigations has generally been limited to visual comparison of broadscale soil composition. More-over, there is still a general lack of awareness among the legal profession and police forces as to the true potential of soil forensic science.

It is the complex nature of soil, and our ability to characterise soil components in detail, that provides powerful evidential value. Analysis of soil can provide information about geographic origin and land-use vegetation, thus potentially providing valuable intelligence to criminal investigations.

Traditional methods applied to soil forensics have proven themselves in courts of law, through the judgement and testonomy of an expert witness, and include:

• visual comparison of colour,
• particle mineralogy,
• palynology (identification of pollen and spores).

Recent years have seen significant analytical advances in profiling methods that can be applied to soil. For example Infa-Red radiation can be used to provide a general profile of soil chemistry, XRDP can provide a detailed fingerprint of the mineral components of soil, while advances in molecular microbial methods can be applied to fingerprint the biological component of soil.