Soils, rocks, and other minerals may be found on a suspect's body, shoes, clothing, or vehicle. They may be
found on tools used in a crime, on a victim, or elsewhere at the crime scene.
Keep these and other sources of trace evidence in mind. Be diligent in your search for them at the scene, on
the suspect, or on equipment he has used. Note stains, spots, and pools of liquid within the scene and treat them
as evidence. Fluid samples may be collected with a clean medicine dropper and refrigerated.
Your collecting of evidence from an injured victim at a crime scene will be very limited. Usually, you only
make a quick observation of the victim's dress, general condition, and the nature of the victim's wounds or
injuries. In some cases even this much cannot be done before seeking medical care.
The investigator who goes to the hospital to interview the victim should collect, or make arrangements to
collect, items of physical evidence and certain evidence standards that may be needed in the case. For example,
when it is apparent there was physical contact between a suspect and a victim, the victim's clothing should be
recovered. Wrap each item separately and mark it.
If a victim reports having slapped at or clutched a suspect, fingernail scrapings should be collected. If a
victim's injuries result in bleeding, get a sample of the victim's blood for typing by the crime lab. Get a sample
even if the pathologist will run extensive blood tests. If blood is involved, the crime lab will want to run its own
The nature and the exact location of any of a victim's wounds or injuries should be learned from the
examining physician. Make arrangements to photograph bruises suffered by the victim. Photographs of bruises
should be taken as soon as possible, because bruised areas tend to change appearance rapidly. Photographs
should also be taken at 24 hours, 48 hours, and 72 hours after the incident to show changes in coloration of the
bruised area. Changes in coloration aid in determining time and date of the injury.
In the case of a deceased victim, your search for evidence at the scene will be detailed. Before a body is
moved -- even slightly -- its position and everything concerning its discovery must be photographed and recorded
in detail. First photograph the body to show its position in relation to the scene. Note the position of the limbs in
reference to the body. Then, take close-up photos to show details of wounds or injuries and of the positions of
apparent evidence items with respect to the body. Then take measurements and draw your sketches. After these
details have been recorded, a thorough search of the body may begin.
Examine the body for minute items of evidence like hair and fibers, paint, or glass chips. Your most
important action is to ensure that the position of the evidence on the body is recorded precisely. The quality of
trace evidence is often determined as much by where it was found as by what it is. Thus, glass slivers found in
the seam of the left shoe should be recorded in such a way that all details are shown.