Crime Scene

1
Crime Scene

• Processing the Crime Scene

2
Processing the Crime Scene

• Physical evidence encompasses any and all
  objects that can establish that a crime has been
  committed or can provide a link between a crime
  and its victim or a crime and its perpetrator.

3
Secure and Isolate the Crime Scene

• Responsibility?

4
Secure and Isolate Cont

• Once the scene is secured, lead investigator
  establishes

5
Record the Scene

• Since the crime scene will not remain in its
  original state for very long, a permanent record
  of the scene must be made as soon as possible.
  These records are also required at trial.

6
Record the Scene

• The three methods of recording the scene are done
  in the following manner

7
(No Transcript)
8
Record Scene Photography

• Photography
• the scene should be photographed in an unaltered
  condition. Unless someone is injured, everything
  should be left in its original condition until
  all evidence is photographed.

9
Record Scene Photography

• What should be photographed?

10
Record Scene Photography

• What should be photographed? Cont

11
Record Scene Photography

• Close-up Photos of Physical Evidence with a ruler
  or something else to show size/scale (point of
  reference)
• Videotaping/digital cameras can also enhance the
  preservation of the evidence in its original
  state
• Still photography is still the best for its detail

12
Record Scene Rough Sketches

• after photos, the investigator will sketch the
  scene (see diagram)

13
(No Transcript)
14
Record Scene Rough Sketch

• Why?

15
Rough Sketch Cont

• All objects are measured from two fixed points (
  ) accurately with
  a tape measure (NOT GUESS)
• Each object is then given a letter and a legend
  or list will correlate the letter to the item
• The sketch should always designate North

16
Rough Sketch Cont
17
Record Scene Finished Sketch

• A finished sketch will be made from the rough
  sketch and will then be drawn to scale using the
  measurements provided in the rough sketch. (This
  is what will be used as evidence in court.)

18
(No Transcript)
19
Record Scene Notes

• Note taking is a constant activity throughout the
  processing of the crime scene and include
• Detailed written description of the scene with
  the location of physical evidence recovered
• Must identify the time the evidence was
  discovered, by whom, how and by whom it was
  packaged and marked and disposition of the item
  after it was collected
• Tape recording notes is a helpful tool, but at
  some point the tape must be transcribed

20
Searching the Scene

• Types of Searches (See Diagram) searches at the
  crime scene must be systematic and the type of
  search will be determined by locale and size of
  the area and actions of victim and suspect at the
  scene

21
Searching the Scene
22
Searching Cont

• The physical evidence that should be collected
  include hairs, fibers, blood, glass, soil, fabric
  impressions (in a car or on furniture)
• Particular attention is paid to cross-transfer of
  evidence between the perpetrator and the weapon
  and/or victim
• Clothing from the suspect may be collected and
  must be bagged separately
• Areas of the crime scene may be vacuumed and the
  sweeping submitted to the lab for testing

23
Vacuum Equipment
24
Searching Cont

• The following items obtained from the body should
  be sent to the lab for testing

25
Collect and Package Physical Evidence

• Physical evidence must be collected in such a way
  that prevents any change between the crime scene
  and the crime lab
• Hairs, blood and fibers should not be removed at
  the scene. The article it is on should be sent to
  the lab intact and the evidence removed there.

26
Collect and Package Cont

• Blood stains can be removed by either scraping
  and transferring to a moistened swab or cutting
  out the stain
• EACH DIFFERENT ITEM MUST BE PACKAGED
  SEPARATELY!!!
• Many materials can be used to package evidence
  plastic pill bottles, manila envelopes, and vials
  etc.

27
Collect and Package Cont

• Blood (and all clothing) SHOULD NEVER be packaged
  in an air-tight plastic container
• Why?
• Any charred debris SHOULD be packaged in an
  air-tight container
• Why?

28
Maintaining a Chain of Custody

• Continuity of possession (chain of custody) must
  be established whenever evidence will be
  presented in court
• EVERY PERSON WHO HANDLED THE EVIDENCE MUST BE
  ACCOUNTED FOR!!!!
• Evidence is carefully packaged and marked at the
  crime scene (collectors initials, date of
  collection, location of evidence)

29
Chain of Custody Cont

• Whenever a transfer of evidence occurs it must be
  recorded
• Chain of custody should be kept to a minimum

30
(No Transcript)
31
Obtain Controls

• When possible, any collected evidence (hair,
  fibers, soil, etc.) should be compared with a
  control (known sample) from the actual crime
  scene
• Bloodstain evidence must be accompanied by whole
  blood or buccal swab controls which are obtained
  from all relevant crime scene participants

32
Submitting Evidence to the Lab

• Evidence submission forms are required for all
  articles to be tested
• Case history should accompany the evidence
  submission form so the analyst can examine the
  evidence in a logical sequence
• The particular type of test should be noted, but
  analyst is not bound only to that test

33
Submitting Evidence Cont

• Each item for testing must be listed, packaged
  separately and assigned a number or letter

34
Crime Scene Safety (see guidelines)

• See text pgs 47 - 50

35
Legal Considerations at the Crime Scene

• Any evidence at the scene must be removed in
  compliance with 4th Amendment privileges.
• Allowances for a warrant-less search

36
Legal Allowances Cont
37
Mincey v. Arizona

• under the pretext of buying drugs, police forced
  entry into Rufus Minceys apartment and an
  undercover officer was killed
• over a 4 day period police gathered evidence
  without a warrant
• Mincey was convicted but appealed saying the
  evidence was collected without a warrant or his
  consent

38
Mincey v. Arizona Cont
39
Michigan v. Tyler

• a fire burned down Tyler and his partners
  business
• police were prevented from immediately searching
  the scene due to smoke, darkness, etc.
• the next morning evidence was collected and
  removed

40
Michigan v. Tyler Cont

• 4, 7, and 25 days later more evidence was
  collected without a warrant and was used to
  convict Tyler and his partner of arson
• The Supreme Court says.

41
Court Case Conclusion

• The Moral of the Story
• OBTAIN A SEARCH WARRANT BEFORE INVESTIGATING AND
  COLLECTING PHYSICAL EVIDENCE!!!!!