Targeted Forensic Reference Collection
Definition
A set of soil samples collected specifically for a case, from the geographic area relevant to that investigation. It supplements national survey data with the fine-scale resolution a forensic comparison requires.
- Field
- Forensic geology
- Purpose
- Case-specific soil comparison samples
- Scope
- Geographic area relevant to the investigation
- Relation to national data
- Supplements coarser survey databases
Common questions
Why can't a national soil survey substitute for a targeted collection?+
National surveys are typically mapped at a scale too coarse to distinguish soils from adjacent fields or nearby properties, while forensic comparison often needs to discriminate a specific scene location from a suspect location only metres or a few kilometres apart, which requires site-specific sampling.
When in an investigation is a targeted reference collection typically built?+
It is usually assembled once a scene and one or more comparison locations, such as a suspect's vehicle route or property, have been identified, so the sampling can be designed around the actual questioned and known sites rather than collected speculatively.
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