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Circumstantial evidence is indirect evidence that can be used to imply a
fact but that does not directly prove it. No one, other than the suspect and
victim, actually sees when circumstantial evidence is left at the crime scene.
But circumstantial evidence found at a crime scene may provide a link
between a crime scene and a suspect. For example, finding a suspect’s gun
at the site of a shooting is circumstantial evidence of the suspect’s presence
there.
Circumstantial evidence can be either physical or biological in nature.
Physical evidence includes impressions such as fingerprints, footprints, shoe
prints, tire impressions, and tool marks. Physical evidence also includes
fibers, weapons, bullets, and shell casings. Biological evidence includes
body fluids, hair, plant parts, and natural fibers. Most physical evidence,
with the exception of fingerprints, reduces the number of suspects to a
specific, smaller group of individuals. Biological evidence may make the
group of suspects very small,