CHAPTER 5 (p.79)

1
CHAPTER 5 (p.79)

• THE CRIME SCENE FOCUS

2
INTRODUCTION

• CRIME SCENE- A location at which a suspected
  criminal offense has occurred
• Processing the crime scene is one of the most
  important parts of criminal investigation.
• Crime scenes contain physical evidence.
• Locards Transfer of Evidence theory- Entry
  brings evidence exit takes evidence.

3
CRIME SCENE

• Early investigators relied upon interrogations.
• Confessions are less important today.
• Confessions must be corroborated by physical
  evidence.
• Even eyewitness testimony is very inaccurate.

4
CRIME SCENE (Cont.)

• Accurate observation and recording is essential.
• Seemingly unimportant evidence may have great
  evidence in the investigation and trial.

5
EVIDENCE

• All evidence should be collected and processes
  with equal competency and thoroughness.
• Protect the crime scene- contamination-Remember
  Locards theory.
• Searching and recording- thoroughly
• Collection- Get all evidence- transport right
• Transportation- CHAIN OF CUSTODY

6
CHAIN OF CUSTODY

• Appoint one officer as evidence custodian.
• Everyone search, but ONLY one collects.
• You must document EVERY time evidence changes
  hands
• Breaks in the Chain of Custody will cause
  challenges in Motions to Suppress.

7
RECONSTRUCTION

• Investigator must reconstruct what happened at
  the crime scene.
• Crime scene types
• Indoor
• Outdoor
• World Trade Center Bombing
• 1400 vehicles processed

8
CRIME SCENE

• May be both indoor and outdoor
• Abduction of victim from home.
• Victim taken to wooded area
• Crime scenes may be multiple with multiple
  offenses.

9
RESPONSE TIME

• RESPONSE TIME- important that the first officer
  get to the scene as rapidly as possible.
• PROTECT THE CRIME SCENE
• Crime scene may become contaminated.
• Remember Locards principle. Theory of Transfer)
• Police officers are the worst offenders.

10
RECORDING THE SCENE

• Crime scene photos
• Coordinated photo series
• Objectively record the scene
• Photographic distortion

11
DIGITAL PHOTOGRAPHY

• Somewhat suspect because it can be altered-
  Defense atty. May attack its use.
• Take hundreds of photos and then transfer to a
  file for use of investigators
• Very good quality pictures
• Start close-up then move out.
• Measurement marker
• Record identifications on photos

12
IDENTIFICATION DATA

• 1. Subject
• 2. Location
• 3. Photographer
• 4. Case number
• 5. Time of dat- to the minute
• 6. Date of photograph
• 7. Photo series number
• 8. Weather, equipment, shutter speed

13
CRIME SCENE SKETCH

• See page 85- 86 in text.
• Rectangular Coordinate Method- straight line.
• Triangulation- measure from two fixed points.
• Projection- exploded sketch

14
CRIME SCENE SKETCH

• Must be accurate- re-measure
• Use pencil for rough sketch
• Final drawing in permanent ink
• Electronic systems are available

15
SKETCH REQUIREMENTS

• 1. Investigator name and identification
• 2. Location- City, State, Street address, Room
  location
• 3. Date and time of rough sketch
• 4. Evidence listing- Location by number
• 5. Case number
• 6. Directional arrow (compass heading)
• 7. Note Not to Scale or show scale

16
SEARCHING THE CRIME SCENE

• Primary reason- locate evidence
• Contamination
• Train officers
• Record name of everyone on scene- time of entry,
  reason for being there, time left
• Public expectations- crime shows distort

17
SEARCH METHODS

• See page 91 in text.
• STRIP SEARCH METHOD
• SPIRAL SEARCH METHOD
• SECTOR SEARCH METHOD
• GRID SEARCH METHOD

18
PHYSICAL EVIDENCE

• Record the location and photograph before
  collection- Record the
• 1. Time and date
• 2.Location of discovery
• 3. Investigator and identification info
• 4. Item description
• 5. Identifying marks on items
• 6. Names of witnesses to finding evidence

19
EVIDENCE RECOVERY

• 1. Suspect identification
• 2. Establish offenders MO
• 3. Proving or disproving an alibi
• 4. Connecting or eliminating suspects
• 5. Identify stolen items or contraband
• 6. Victim identification
• 7. Provision of investigative leads
• 8. Proving a statutory element of the crime

20
CHAIN OF CUSTODY (Cont.)

• EVERY TIME an item of evidence is moved the
  transaction must be recorded on the evidence
  sheet.
• Record on individual package when found
• Record all items on an evidence sheet
• Lists items, dates, locations, and responsible
  persons
• Initiate when found, update when placed in
  evidence room, each time it is moved

21
EVIDENCE COLLECTION

• TWO STAGE SEARCH- Large and small items- care not
  to contaminate trace evidence- handle as little
  as possible
• Obliterating fingerprints
• Leaving officers own fingerprints
• Fibers, hairs, liquids, bodily fluids
• Use tweezers, forceps
• May use special vacuum cleaner

22
CRIME SCENE RESOURCES

• GBI ASSISTANCE IS GREAT
• Trained in crime scene processing
• Competent in forensic evidence
• Has tools and test equipment
• Can focus only on your crime scene
• Stay until processing is complete
• Testify in court- Chain of Custody

23
MARKING EVIDENCE

• The types of mark of an item depends on
• 1. Size of the object
• 2. Physical nature (solid or liquid)
• 3. Value of the object
• 4. Number of like objects

24
PACKAGING EVIDENCE

• 1. Package items separately.
• 2. Use clean packaging.
• 3. Use evidence tape to seal packages
• 4. Dont fold cloth items unnecessarily
• 5. Dont remove from container if possible
• 6. Use crime lab request for lab work
• 7. Send evidence in registered mail RRR

25
PACKAGING (Cont.)

• Organic items- (marijuana)- package in paper
  evidence bags- putrefaction- lose THC
• Other un-refrigerated items- (dry items) package
  in plastic evidence bags
• Refrigerated items- (blood) package in vials-
  vials in plastic evidence bags

26
THC

• TETRAHYDROCANNABINOL
• The illegal substance in marijuana

27
EVIDENCE STAGING

• STAGING- Attempt to redirect the investigation
  away from the logical truth
• Protect victim or family
• Conceal another crime- arson, fake burglary,
  sex crime stigma

28
EQUIVOCAL SCENES

• EQUIVOCAL SCENES- Open to interpretation
• Knife in chest may indicate suicide, accident, or
  homicide
• Knife in chest is physical evidence-
  circumstantial because it does not prove who did
  it, only who was there when the victim was stabbed

29
PERSONATION

• PROFILING!!
• Offenders reflect their own personality traits in
  crimes they commit.
• Remove only certain items
• Position the body
• Punish corpse after death
• Suspect imparts identifying meaning
• SIGNATURE ACTIONS

30
CRIME SCENE EQUIPMENT

• See p.98 for list of items

31
SPECIALIZED CSI

• 1. All Investigators are trained as CSI but
  depending upon their agency training is varied.
• 2. Half PD in country have lt10 employees
• 3. CSI Crime shows are unrealistic- cause
  overoptimistic expectations.

32
EFFECT ON PUBLIC/ JURIES

• CSI Effect causes public to expect DNA,
  fingerprints, firearms testing, hairs, fibers and
  other TV activity.
• Absence of CSI info may mean acquittal
• Most Criminalists work in the laboratory, not on
  crime scenes.
• DONT WATCH CRIME SHOWS- THEY ARE BAD FOR YOU!!!

33
(No Transcript)
34
(No Transcript)