Transcript Forensic Anthropology Crime Scene Recovery

Field Survey & Burial
Recovery
Forensic Science I
Part I:
The Crime Scene:
Discovery and
Recovery
At the Crime Scene
• The first person on the crime scene
is usually a police officer.
• Their first job is to:
–Take care of emergencies.
• Get medical attention for any
victims
• Disarm/arrest perpetrators.
• Next, they secure and isolate the
crime scene to prevent unauthorized
access to the area:
– Erect ropes or barricades
– Position guards
– Identify & Separate Witnesses
Take no more than 6
hours
Posted Sentry with
Access roster
Re-route parking lot cars
& Students
Crime Scene
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Close two lanes of traffic,
open other two, but
make them 1 way
Recording the Crime Scene
Photograph the Scene
•Scene should be unaltered
•Entire area should be
photographed, in addition to
adjacent areas
•Many angles should be used
Recording the Crime Scene
Photograph the Scene
oPosition and location of body and
other evidence should be shown
oClose-up pictures of injuries and
weapons
oUse a scale to show size of an
object
oVideotaping is another option
Recording the Crime Scene
Sketching the Crime Scene
This is a rough sketch
Should show accurate measurements
Must show all relevant evidence
Has a legend below drawing
Should have compass heading designating
north
A finished sketch can be done later (using
CAD or other computer software)
To Sketch a Crime Scene:
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Observe and plan
Avoid destruction of evidence
Identify what is relevant
Stand at doorway and start sketch
there (if you’re indoors)
• Always search and sketch in the
same way, to establish uniformity
in procedure (for court testimony)
To Sketch a Crime Scene:
• Measure distances & outline the area
• Measure from permanent, fixed
objects
• Position sketch so North is at top
• Determine scale
• Use approximate shapes for
sketching objects
Recording the Crime Scene
Taking Notes About the Crime Scene
Detailed written description of the scene
Location of items of evidence recovered
Describe who discovered evidence,
who packaged evidence, where
evidence went once packaged
Chain of Custody
Recording the Crime Scene
Taking Notes About the Crime Scene
Used to “refresh” investigators’
memories – often years after the
crime
Notes can be taped rather then
written (they will have to be
transcribed later)
Crime Scene Search
– A systematic search for evidence
must be planned and executed.
– Types of search patterns
– Spiral
– Line or Transect
– Grid method
• Evidence to be collected depends on
the crime committed, including:
• Evidence a crime was committed
• Evidence of how the crime was
committed
• Evidence of who committed the
crime
Jessica Ridgeway murder search
Systematic
Search
• Thorough & systematic
• No pertinent evidence
overlooked!
• This insures factual &
unbiased reconstruction
• Advisable to have one
person supervising and
coordinating the
collection of the
evidence
• Physical evidence can
be anything from
massive objects to
microscopic traces
• Collection and Packaging of Evidence
– Avoid Contamination!
– If possible evidence should be submitted
intact (entire article of clothing, etc.)
• Hairs, fibers, blood should not be
removed from clothing
• Trace evidence should be collected with
forceps and placed in bottles, pillboxes,
envelopes, or screw-cap glass vials.
• Bloodstained materials should NOT be
stored in air-tight containers (mold)
• Items from the scene of a suspicious fire
MUST be stored in air-tight containers.
Chain of Custody
• Every person who
handled or examined
evidence must be
accounted for
• Everything must be
carefully marked
• Controls must be obtained
– Samples to compare for
comparison
• Test for Contamination
• Test for match (suspect)
Safety and Legal Issues
• Fear of AIDS, Hepatitis, other Pathogens
– Latex gloves and protective shoe covers
– Particle mask and goggles if dust present
– Anything that comes into contact with
potentially infectious materials (fingerprint
brushes, gloves, pencils, etc.) should be
placed into biohazard bag
– No eating, drinking, or smoking
at crime scene
Legal Search & Seizure Issues
• Fourth Amendment guarantees against
unreasonable searches and seizure
• Need a Warrant to search, except:
– Emergency circumstances
– Need to prevent immediate loss or
destruction of evidence
– Search of a person lawfully arrested
– Consent of parties involved
Part II
How do we find buried remains?
Field Survey
Aerial Survey
Canine
Survey
Remote
Sensing
Survey
Crime Scene Search Methods
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Linear (Strip)
Grid
Wheel
Spiral
Zone
Link
Linkage Theory
Crime Scene
Victim
Evidence
Suspect
If all else fails, walk every inch of the ground
– via Pedestrian Survey
Linear Transect Ground Survey
Find Evidence
of Disturbance
Isolate the
Disturbance
Then,
Excavate
Recovering the Remains
• You’ll need these tools:
– Smooth tipped shovel; sharpened trowels;
screen sifters; paint brushes; and buckets
• A meter grid is utilized for documentation
• Photographs should be taken as items are
uncovered
– Each bone, clothing item, etc. should be
photographed in its original position
Recovering the Remains
• Vegetation and insects
should be collected
• Remove dirt one grid at a
time (10cm at a time)
– Avoid the temptation to dig to
the bottom of the grave
• Soil should be sifted to
ensure that evidence is not
missed
– When something is found, it
should be labeled with the
grid number and depth
– Provides a 3-D picture of
where evidence was
collected from
Recovering the Remains
• Size and depth of the
grave can tell whether
the grave digger was
rushed
• Expose the entire
skeleton, before you
begin to pull bones or
fragments out
• Fresh remains (fleshy)
should be recovered in a
body bag, or container
Recovering the Remains
• Damp clothing, wallets, etc. should be placed in brown
paper bags and allowed to air dry
• Fully skeletonized remains should be bagged separately
• After the removal, search under the body
– Bullets; gloves; guns; knives; etc.
– Soil can contain important info!
• Insects, chemicals, etc.
Forensic Anthropology
• Anthropologists have
the ability to:
– Analyze human remains
for clues as to age, sex,
race, etc.
– Recover burial remains in
an efficient manner
– Analyze the scene and
gravesite for clues as to
what occurred
– Find relevant clues on
bones and teeth to
determine COD
QUESTIONS??????