1. 2.3 Class/Individual Evidence
Unit 2: Evidence
2.3 Class/Individual Evidence

2. Class vs Individual
Physical evidence is broken into two main categories:
Class Evidence: characteristics common to a group of similar objects or persons.
Individual Evidence: can be linked to a unique, single, specific source or person.

3. Purpose of class evidence
To refine the pool of suspects.
Size 11 shoe print found at scene.
Guarantee suspect left print?
Guarantee suspect has a size 11 shoe?
No, but it does help focus the
investigation.

4. Class vs Individual Evidence
Which examples do you think could be individual evidence?

5. Class vs Individual Evidence
These fibers are class evidence; there is no way to determine if they came from this garment.
The large piece of glass fits exactly to the bottle; it is individual evidence.

6. Class or Individual?
A pistol was found in a theatre where a man was shot. A suspect known to have owned a Derringer like this one was apprehended.
Would this gun be considered individual or class evidence?

7. Class or Individual?
Can it be determined whether theses bullets were fired from the same gun?
How can bullets be individualized to a gun? Explain.

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