Locard's Exchange Principle Applied to Geology
Definition
When a person contacts an earth surface, geological material transfers bidirectionally. The suspect carries material from the scene; the scene receives material from the suspect. Both directions are investigatively useful and both are subject to the transfer, persistence, and recovery framework.
- Core claim
- Bidirectional transfer of geological material on contact
- Applications
- Suspect carries scene material; scene receives suspect material
- Governing framework
- Transfer, persistence, and recovery
Common questions
Why is bidirectional transfer significant for geological trace evidence?+
It lets investigators link a suspect to a scene from either direction: material found on the suspect matching the scene, or foreign material at the scene matching a location known to the suspect.
What limits the usefulness of transferred geological material in a case?+
How well the material persists on the surface it transferred to, and whether it is recovered before it is lost, contaminated, or mixed with material from other sources.
Related terms
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