‘Crime Scene Management
• Exhibit understanding of proper evidence collection practices
o Procedure for collecting evidence
▪ All material gathered during a criminal investigation must be carefully
collected, recorded, classified, processed, and stored
▪ All evidence must be marked for identification and protectively packaged
● If officers fail to follow proper procedures the “chain of evidence”
may be broken, tainting evidence and making it inadmissible in
court
o Chain of Evidence Sequence
▪ Identification and collection
▪ analysis
▪ storage
JN
▪ Preservation
▪ Transportation
▪ presentation in court
▪ return to owner
● The chain of evidence shows
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o who obtained the evidence
o where and when the evidence was
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obtained
o who secured the evidence
o who had control or possession of the
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evidence
• Exhibit knowledge of scientific principles involved in crime scene management
o Four components of a crime scene
▪ Information management
● Information can: link a suspect to a crime scene, approve or
disapprove an alibi, or develop investigative leads
● Can be in oral form, written statements or documents, or patterns
● Various types of information can be used to solve crimes
o Comprehensive victim background check
o Inquiry into the suspects whereabouts and belongings
within the past 24 hours of the proceeding crime
▪ Manpower management
● The agencies responsible for the crime scene processing and
construction
● Factors of manpower management that affect crime scene
management
o Insufficient personnel
, NOCTI Test Study Guide 2
o Poor training and lack of experience
o Overworked crime scene team
▪ Technology management
● Money allocated for purchasing and updating equipment should be
should be adequate to the variety of crime scenes encountered by
the team/unit
● Adequate training to personnel to properly utilize new technology
and equipment
o Categories of equipment
▪ Support vehicles
▪ Communication- two way radio, computer
▪ Tools and search equipment- metal detectors,
forensic light tools
▪ Specialized crime scene kits- latent print kits
▪ Chemicals and reagents-blood print enhancement
reagent, latent print developers
JN
▪ Portable instrumentation-portable laser, night vision
equipment
▪ Evidence packaging materials and related forms
▪ Management of logistics
● Logistical concerns should be properly addressed through good
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planning, organization, and efficient distribution of resources- to
be established earlier in the investigation
o Elements to be established
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▪ Command posts
● A command post should be situated outside
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the perimeter of the working crime scene
away from the evidence location
▪ Media relations
● Care should be taken to restrict access to the
crime scene and a separate area should be
identified for members of the public and
media
▪ A shortage in one of these areas, or an over emphasis of a component will
result in a system that is out of balance and that will jeopardize the overall
management of the crime scene investigation process
• Exhibit understanding of proper evidence preservation practices
o Proper evidence preservation
▪ The preservation of all items of physical evidence relating to felony
crimes, regardless of whether an individual files a petition for post-
conviction DNA testing.
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▪ The retention of crime scene evidence that is associated with unsolved
cases.
▪ The retention of all items of physical evidence secured in connection with
a felony for the period of time that any person remains incarcerated, on
probation or parole, involved in civil litigation in connection with the case,
or subject to registration as a sex offender.
▪ Provisions enabling courts to determine the appropriate remedy when
evidence is improperly destroyed.
● Procedures for collecting evidence (examples)
o Secure the scene
o Liquid pools of blood should be absorbed with a gauze pad
and frozen or refrigerated asap
o Hair should be picked up with tweezers and stored in a
paper bindle or coin envelope then labeled
o In rape cases the pubic region should be combed prior to
collecting standards (30-60 pubic hairs are required).
JN
Obtain hair samples from the victim, suspect, and any other
possible sources for comparison. Have the victim and
suspect bend over a large sheet of white paper and rub their
hands through their scalp so loose hairs will fall out. (50-
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100 hairs are desired)
o Wrap recovered bullets in paper and seal in a separate,
secure pill box or envelope
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• Exhibit understanding of initial crime scene management
o Note taking
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o Securing the crime scene
▪ Locking down the crime scene
▪ Setting up crime scene perimeters
▪ Establishing a path of contamination
▪ Establishing crime scene security
o Evidence management
o Scaling the investigation to event
• Identify and/or perform latent print techniques
o Latent print
▪ Impressions produced by the ridged skin, known as friction ridges, on
human fingers, palms, and soles of the feet.
o Technique Examples
▪ Powders
● Adhere to both water and fatty deposits.
● Useful on newer prints only.
● They’re useful on any dry, relatively smooth, non-adhesive
surfaces.
▪ Silver nitrate
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● Reacts with the chlorides in skin secretions to form silver chloride,
o A material which turns gray when exposed to light.
● Developed prints must be photographed immediately because the
reaction will permanently fill the background.
● Useful on paper, cardboard, plastics and unvarnished, light-colored
woods.
● Not useful on items which have been exposed to water.
▪ Ninhydrin
● Reacts with amino acids to produce a purple reaction product
called “Rhuemann’s Purple”
● It is useful on porous surfaces—especially paper.
● Development time is up to 10 days,
o but may be accelerated through the application of heat and
humidity
● Not useful on items which have been exposed to water.
• Identify and/or perform crime scene diagramming
JN
o Crime scene diagram
▪ A crime scene diagram visually documents the setting of a crime as it
appeared when it was discovered.
▪ includes a layout of the environment, location of the victim(s), blood
splatter, possible items of interest like weapons, footprints, dirt, clothes
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▪ written details and pictorial evidence
o To Make a Crime Scene Diagram
▪ Set the crime scene
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▪ Add symbols
▪ Set scope of the scene
▪ Gather information
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▪ Create the background, floor, and landscape
▪ Add details
▪ Label
▪ Verify accuracy
Use of Force