PHYSICAL EVIDENCE MANUAL - Crime Scene Investigator Network

Physical Evidence Manual
• Clothing
• Personal belongings
Note observable evidence (e.g. weapons, bloodstain patterns, attempts to modify
scene, etc.)
Record and Collect Physical Evidence
• Photograph all items in place before collection, with and without a scale.
• When possible, have one person act as an evidence custodian. This
individual will collect, package, and record all evidence.
• Focus first on the evidence that could be readily lost (e.g., loose fibers and
hairs) and leave the least transient evidence for last. If a body is at the
scene, move it last. Under Oregon law only the Medical Examiner or
District Attorney can approve the removal of the body.
• Ensure collection and packaging is sufficient and appropriate for the
evidence.
• Consider whether the evidence could have been moved inadvertently. Do
not attempt to replace evidence if it was moved. Interview medical
personnel or first responders to assess their movements in the scene and
their possible effect on the position of evidence.
• Consider whether or not the scene and evidence appear intentionally
contrived, staged, or otherwise altered.
• Do not handle evidence excessively. Allowing others to observe or handle
the evidence simply to satisfy curiosity can compromise delicate evidence
such as DNA, latent prints, or trace evidence.
• Evidence containing blood or other biological fluids should be completely
air-dried before it is packaged and submitted to the laboratory.
• Evidence contaminated with wet blood or potentially infectious materials
should be secured and transported in a leak proof container prior to airdrying.
Remember that packaging wet items (e.g. blood soaked clothing)
may destroy useful bloodstain patterns if folded up wet.
• Mark evidence packaging. If you mark the actual item be careful not to
destroy, contaminate, or obscure forensically important detail on the
evidence.
• Obtain the appropriate standards.
• Obtain the appropriate controls.
Conduct Final Survey
• Discuss the search jointly with all team members for completeness.
• Check to ensure all evidence, including film, is accounted for before
departing scene.
• Make sure any possible hiding places or difficult access areas have not
been overlooked during the search.
Adopted: May 2002
Revisions: 6
Last Revision: January 31, 2008
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