THE CRIME SCENE
CHAPTERS 4 & 5
PROCESSING THE
CRIME SCENE
DEFINING A CRIME SCENE
 Primary Crime Scene
 Secondary Crime Scene
 Macroscopic
 Microscopic
PHYSICAL EVIDENCE
 Relation between
 VICTIM
 SUSPECT
 SCENE
 OBJECTS
 PHYSICAL EVIDENCE
INFORMATION FROM EVIDENCE
 VERIFY STATEMENTS
 IDENTIFICATION OF SUSPECTS
 AFIS, CODIS
 SUBSTANCE IDENTIFICATION
 DRUGS, ACCELERANTS,
 SCENE RECONSTRUCTION
 INVESTIGATIVE LEADS
LOCARD’S EXCHANGE
PRINCIPLE
Whenever two objects
come into contact, a
mutual exchange of
matter will take place
between them.
SCIENTIFIC METHOD
 METHODOLOGICAL
 SYSTEMATIC
 LOGICAL
 APPLICATION OF KNOWLEDGE
CRIME SCENE MANAGEMENT
 ABILITY TO SOLVE CRIME A TEAM
EFFORT
 INFORMATION MANAGEMENT
 MANPOWER MANAGEMENT
 TECHNOLOGY MANAGEMENT
 LOGISTICS MANAGEMENT
FIRST RESPONDERS
 Assist the victim
 Search for / arrest suspect
 Detain witnesses / keep separate
 PROTECT CRIME SCENE / LOG
 DO NOT SMOKE, DRINK OR EAT
 Infect self
 Contaminate scene
 Communicate all information to detectives
CRIME SCENE PROCEDURES
 SECURE SCENE
 SURVEY SCENE
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Minimize contact by ALL personnel
Use Personal Protective Equipment
Note evidence
Protect evidence that may be lost
Note weather conditions
Use alternate entry
Record EVERYTHING
APPROACH THE
SCENE
SECURE AND
PROTECT THE SCENE
PRELIMINARY SURVEY
OF THE SCENE
NARRATIVE:
DESCRIPTION
OF THE SCENE
CRIME SCENE
DOCUMENTATION
 NOTES
 VIDEO
 PHOTOGRAPHY
 SKETCHES
CRIME SCENE
DOCUMENTATION
 NOTES
 Immediate
 Accurate
 Continuing
 VIDEO
 3D Documentation of scene
 Orientation of scene but no narrative
 DO NOT EDIT
PHOTOGRAPH
THE SCENE
CRIME SCENE
DOCUMENTATION
 PHOTOGRAPHY
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BEFORE MOVING EVIDENCE
SYSTEMATIC
OVERVIEW
MIDRANGE
CLOSE-UP
LOG / CAMERA SETTINGS
SCALE
Three Types of
Photographs
 1. Overall
 2. Midrange
 3. Closeup
CRIME SCENE
DOCUMENTATION
 SKETCHES
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Assign measurements to objects
Triangulation
Baseline
Polar Coordinates
Rough / finished
Legend
SKETCH THE
SCENE
Rough Sketch
Finished Sketch
CRIME SCENE SEARCH
 SYSTEMATIC / METHODICAL
 LINE
 GRID
 ZONE
 WHEEL
 SPIRAL
Search Patterns
EVALUATION OF THE
PHYSICAL EVIDENCE AT
THE SCENE
COLLECTION & PRESERVATION
OF PHYSICAL EVIDENCE
 One CSI in charge
 Priority to easily destroyed evidence
 Primary packaging
 Contain and protect
 Secondary packaging
 Seal and tamper resistant
 INITIAL / DATE / TIME
 Identity of item enclosed
Evidence Bindles
DETAILED SEARCH OF
THE SCENE
COLLECTION & PRESERVATION
OF PHYSICAL EVIDENCE
 Each item separate
 Wet items
 Temporary in plastic
 Air Dry
 Permanent in paper
 Arson evidence – air tight containers
 Controls
COLLECTION, RECORDING,
MARKING AND PRESERVATION
OF EVIDENCE
 What constitutes a seal?
 Initials on article or container
 Description of contents
 Paper is our friend!
 Evidence Bindle
PROCESS THE SCENE FOR
LATENT PRINTS
AND
COLLECT ANY
PRINTS DEVELOPED
CRIME SCENE
RECONSTRUCTION
 Data Collection
 Conjecture
 Hypothesis Formulation
 Testing
 Theory
FINAL SURVEY!!!
STOP AND THINK OF
ANYTHING FURTHER THAT
MIGHT BE COLLECTED.
RELEASE OF THE
CRIME SCENE