crime scene investigation & documentation. purpose of a scene search to obtain physical...
Post on 20-Dec-2015
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Physical Evidence Physical Evidence must be
recognized, accurately documented, properly collected and transported, and a chain of evidence must be maintained before it can be of forensic value.
Manpower and fiscal restraints must be considered relative to the nature of the crime.
Preservation of the Crime Scene
First officer on the crime scene must: Obtain medical assistance Arrest the perpetrator Secure the scene (to prevent destruction
of evidence) -- May require limiting access to a single room in a motel or sealing off an entire block after an urban fire
Count
Finished files are the results of
years of scientific study combined with the
experience of many years
Once secure, always approached the scene:
in a serious manner (never casually) in an open, unbiased manner (never
have preconceived ideas). Murders have been bungled because the
investigator thought it was a natural death or a suicide
Steps in Scene Investigation
Hands in pocket walk-through to observe scene and plan approach.
Minimum number of investigators. Establish a path of entry and exit
(path least likely used by the criminal).
Never take convenience and expedience over thoroughness.
Homicide Scene
Efforts of Law Enforcement and Medical Investigator must complement at the scene.
Medical Examiner is there just to see body in perspective – their hands on examination happens back in the autopsy lab
Photography
Color photo’s Mirrors in tight places Photograph objects before moving Photograph the scene thoroughly Use scales in photos Videos (beware of the sound) Fisheye Lenses and Virtual Images
Hand Drawn Diagrams
Entirety of the scene can be illustrated
Insert labels and distance measurements
Document the location and relationship of evidence obscured by vegetation, soil, ashes, or other materials
Rough Sketch
Made by the investigator on the scene Not necessarily drawn to scale
(includes proportions and distances) No changes to sketch after leaving
scene Soft pencil, graph paper, straight
edge, compass, clipboard
Elements of Sketching
Scale diagram appropriately Compass Direction with north arrow lnclude essential items only Document the scale (words or figure) Legend with symbols to identify
objects Title with case identification, location,
date, and the sketcher
Rectangular Coordinates
Triangulate from perpendicular boundaries
Bed
Dead guy
2’ from N wall
18” from W wall