As individuals move and interact within a crime scene, evidentiary items may be transferred. This trace evidence includes such materials as hairs, fibers, paint, and glass. Laboratory analysis of trace evidence may be used to associate the material with a particular source or show that material from different areas or persons could share a common source.
In the pictures above, the lawn bag with the victim’s blood inside was found inside the green public garbage can. The tear points and striations in the plastic were matched to the role of lawn bags inside the suspect’s apartment.