How to Conduct the Search
Thorough and conductedwith EXTREME care
Use systematic searcheswith specific patterns
CRIME SCENE
AUTOPSY ROOM
The search for PHYSICAL EVIDENCE extends from the
Medical Examiner will report: results of toxicology & pathology examinations of various body parts, organs, tissues, etc.
Remember that PHYSICAL EVIDENCE can be LARGE or microscopic
Physical Evidence to be sent to the
FORENSIC LABORATORY
•Victim’s clothing•Fingernail scrapings•Head & pubic hairs•Blood (DNA typing)•Vaginal, anal, oral swabs (sex crimes)•Bullets recovered from body•Hand swabs from shooting victims
Collect and package physical evidence
Must package all pieces separately
MUST NOT CHANGE from the time it was collected to the time it is processed by the
crime lab.
Use containers to store hair, fibers, glass and “trace”
evidence.
Must be handled with forceps
(held by gloved hands)
TRY TO AVOID:•Evaporation•Contamination•Breakage
EXAMPLES•Glass bottles•Manila envelopes•Plastic pill bottlesHow to handle
physical evidence
Storing Evidence: Airtight vs Air-Dried?
Airtight
• EVIDENCE from a FIRE (CHARRED)
WHY?
To prevent evaporation of
volatile petroleum residues
Air-Dried
• Blood-stained MaterialsMust be individually dried &
stored in paper bags or manila envelopes
WHY?
To prevent growth of mold & mildew
due to trapped moisture which will
destroy blood
Maintain CHAIN OF CUSTODY
A list must be maintained of all persons
who came into possession
of a particular item of
physical evidence.
Each time an evidence container is opened and closed, it must be sealed w/ a label w/ examiner’s name, date & location of item.
Every time evidence is moved to a different location/lab, the date of transfer must appear on the label.
Failure to do this will lead to serious questions regarding the authenticity and integrity of the evidence and it may not be admissible in court.
Obtain STANDARD/ REFERENCE Samples
• All evidence must be compared to a known sample.
• This known sample is called a standard or reference.
• Most often the known samples come from the victim(s) and the suspect(s).
•Blood•Semen•Saliva•Hair•Fibers•Soil…etc.
Submit EVIDENCE to LABEvidence is delivered to lab personally or by mail delivery
Receiving lab must get:-case history or any such report along with the evidence and
-clear request of the type of examination for each piece of evidence
Analysts may perform other tests on the pieces of evidence
if necessary(in addition to requested tests)
Examples of items that CANNOT be mailed to the lab:
•Explosives•live ammunition•certain chemicals•certain live cultures… etc.
Crime Scene Safety
Crime Scene Investigators (CSI) must protect themselves from exposure to
diseases carried in bodily fluids.
Hepatitis B
Hepatitis C Other diseases
All law enforcement personnel can receive this
vaccination (Occupational Safety & Health Administration (OSHA) Regulation)
HIV / AIDS
CSI Safety Guidelines• Double layer of latex gloves• Protective Tyvek® shoe covers• Tyvek ® or Kleengard ® coveralls or suits (liquid repellant)• Particle mask/respirator, goggles/face shield to prevent exposure to dust, mist,
body fluids, etc.• Be aware of sharp objects like broken glass, knives, needles, etc.• Use biohazard labels when collecting materials hazardous to health.• All gloves, masks, suits must be disposed of in red biohazard bags, taped shut and
sent to a proper facility for incineration.• Note-taking should be done with fresh, uncontaminated gloves to prevent
contamination of pens, pencils and notepads.• Torn or soiled protective gear must be removed immediately and replaced with a
fresh one, AFTER the individual disinfects the contaminated body area with 10% bleach solution, antimicrobial wipes, etc.
• Absolutely no eating, drinking, smoking in the crime scene or laboratory.• All non-disposable items such as cloth lab coats, etc. must be placed in yellow
bags labeled “Infectious linen” and sent to a proper facility for laundering and disinfection.
Legal Considerations at a Crime Scene
The removal of any person or evidence from a crime scene must be done in conformity with
Fourth (4th) Amendment privileges:
The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the
persons or things to be seized.