Crime Scene
Investigation
1
Crime Scene
Investigation
Scenario
• Police have been called to a one-room
apartment to investigate a possible homicide.
The body is on the floor near the center of
the room with what appears to be a single
gunshot to the head. The suspected weapon
is lying nearby.
• Describe how you would go about
investigating this scene, with particular
reference to establishing the integrity of the
crime scene, safety and contamination of any
evidence.
2
Crime Scene
Investigation
Principles of Crime Scene Investigation
•Preserving the Integrity of the Crime Scene
•Recording the Crime Scene
•Searching the Scene
•Collecting & Packaging of Evidence
•Crime Scene Safety
The most important aspects of CSI work include:
Securing the scene
Prevention of contamination
Preservation of physical evidence
3
Crime Scene
Investigation
The Crime Scene Environment
Crime Scene Investigators (CSIs) interact with:
• Police officers (including general duties,
investigative, specialist and administrative areas
Some CSIs are police officers/some are civilian)
• The judicial system including: legal practitioner,
(prosecution and defense lawyers) judges and
courts (including civil, coronial, criminal and
appeal Courts)
• Forensic scientists (including specialist
laboratories and experts)
4
Crime Scene
Investigation
• Forensic medical practitioners (including
pathologists, psychologists and
psychiatrists)
• General community often represented
through juries, including those involved in
specific incidents (victims, suspects,
witnesses) and expectations shaped by
media reporting of actual cases, fictional
material, (books, magazines, television
and movies).
5
Crime Scene
Investigation
Role of the Crime Scene Investigator
• Establish clear and direct lines of
communication and be effective managers:
• At the scene of the crime or incident
• Of the processing of physical evidence
collected from the scene
• Of the investigative process as it relates to
physical evidence
• Of the final presentation of physical evidence
at court
6
Crime Scene
Investigation
When investigating, the CSI should consider:
• Use an entry other than that taken by the
suspect
• Establish the path taken by other persons
first on the scene
• Consider the loss of trace evidence on entry
throughout your examination, (e.g.. shoe/foot
impressions on the floor)
7
Crime Scene
Investigation
• Reassess Occupational Safety and
Health (OSHA) issues
• Establish the extent of the scene and
additional assistance that may be
required
• Establish an entry and exit path for
the Senior Investigating Officer and
specialists to access the scene, if
necessary
8
Crime Scene
Investigation
Boundaries usually start at the
focal point of the scene and
extend outward to include:
• Where the crime occurred
• Potential points of entry and
exit of suspects and witnesses
• Places where the victim or
evidence may have been
moved
9
Crime Scene
Investigation
The basic protocol for scene
processing can be summarized
as several sequenced tasks:
1.
2.
3.
4.
Survey the crime scene
Photograph the crime scene
Map and measuring the crime scene
Record and document the location of physical
evidence at the crime scene
5. Searching for fingerprints and other physical
evidence.
*During the walk-through, a walkway other than the
established path of entry should be used to
reduce contamination.
10
Crime Scene
Investigation
There are generally 6 important categories
of documentation that are applicable to
any search:
Administrative Worksheet
Narrative Description
Photographic Log – overview, specifics
Diagram/Sketch – scaled sketch
Evidence Recovery Log - Identify, Collect
and Preserve evidence
• Latent Print Lift Log
•
•
•
•
•
11
Crime Scene
Investigation
Approach to Searching
• Consider the nature of physical
evidence and the principles of exchange
and transfer. (Locard)
• Each scene is unique and must be
approached with an open mind.
12
Crime Scene
Investigation
• The most transient evidence
should always be collected first,
progressing to the least transient
evidence.
• Moving from the least intrusive
collection techniques to the most
intrusive techniques.
13
Crime Scene
Investigation
• The collection of evidence must
be documented, by recording its
location at the scene, the date of
collection and who collected it.
• For each item collected, a chain
of custody must be established.
14
Crime Scene
Investigation
List of evidence collection guidelines for:
• Bloodstains
• Firearms evidence
• Seminal stains
• Tool marks
• Hair
• Controlled substances &
medicinal preparations
• Fibers
• Questioned documents
• Glass
• Latent fingerprints
• Paint
• Flammable liquids
15
Crime Scene
Investigation
3 Methods to adopt in your
approach to searching
• Positive Approach – what is there
• Negative Approach – what isn’t there
• Information/Intelligence
16
Crime Scene
Investigation
• The positive search which centers on
known facts to locate evidence which is
expected to be found (the tool mark in
the scenario)
• The negative search, which centers on
known facts to indicate that no
evidence, was found to indicate an
alternate explanation (e.g. could the
suspect have entered through another
door)
17
Crime Scene
Investigation
• The intelligent search which requires
a combination of known facts,
consideration for other explanations and
a systematic and thorough approach to
locate any other evidence (finding of
the tip of the pliers, based on
information about a pair of pliers)
18
Crime Scene
Investigation
Searching Patterns or Methods
• There are 5 basic methods that
are universally accepted. These
are:
– Line/Strip method
– Spiral method
– Wheel/Ray method
– Grid method
– Quadrant/Zone method
19
Crime Scene
Investigation
20
Crime Scene
Investigation
• Line/Strip Search Pattern
--One or two investigators start at the
boundary of the crime scene and search in
straight lines across to the other side of
the crime scene.
• Grid Search Pattern
-- Two or more investigators form a grid
by searching in line patterns that overlap
and are perpendicular to each other.
21
Crime Scene
Investigation
• Spiral Search Pattern
--One investigators searches in a spiral path from
the center of the crime scene to the boundary
(outward) or from the boundary of the crime
scene to the center (inward).
• Wheel/Ray Search Pattern
--Several investigators search in straight lines
from the center to the boundary (outward) or
from the boundary to the center (inward).
• Quadrant/Zone Search Pattern
--The crime scene is divided into smaller sections
(zones). One or more investigators are assigned
to search each zone.
22
Crime Scene
Investigation
The area(s) to be searched will often be
determined by the:
• Nature of the incident
• Nature of the physical evidence present
• Location
• Terrain
• Established facts
23
Crime Scene
Investigation
The Golden Rules of a Search
3 Golden Rules to maximize the recovery of evidence:
1. Search areas should be determined to
maximize concentration. Each area
should take no more than 20-40
minutes to search.
2. Breaks should be taken after each
search. (At least 10 minutes)
3. Search the same area twice so that
nothing is overlooked
24
Crime Scene
Investigation
Legal Considerations Regarding Evidence
Circumstances where the police can search for
evidence in the absence of a search warrant:
1. Emergency circumstances
2. To prevent loss or destruction of evidence
3. A search of a person and property in
immediate control of the person as long as it
is in the event of a lawful arrest
4. A search made under consent of the party
25
involved
Crime Scene
Investigation
Purpose of an CSI examination is to:
1. Locate and identify potential evidence
2. Provide information about the crime or
incident
3. Assist in the corroboration or otherwise of
information provided by suspects, victims
or witnesses
26
Crime Scene
Investigation
Type and Scale of Examination
Determined by:
1. Seriousness of the offence/incident,
type of the offence/incident and relevant
circumstances
2. The nature of the scene
27
Crime Scene
Investigation
Before examining evidence, which involves
moving, or disturbing it, the following should
be checked:
1. Ensure appropriate OSHA requirements been
followed (e.g. bio hazards procedures)
2. Has the area or item to be examined been
photographed in place?
3. Ensure adequate notes, sketches and
measurements of the area or item have
been taken?
4. If the area or item is to be moved or disturbed
during the examination, ensure that
evidence will not be contaminated or
destroyed?
28
Crime Scene
Investigation
Prioritize the collection of evidence to
prevent loss of, or damage to, an item.
Smaller items or evidence are usually
prone to damage.
Generally:
1. Ensure fragile evidence is collected first
e.g. latent fingerprints
2. Then collect trace evidence e.g. blood
and fiber
3. Finally, collect larger items
29
Crime Scene
Investigation
Cross Contamination and Biological
Degradation
• Prevent cross contamination and/or
biological degradation.
When collecting an item from the
scene care must be taken to
ensure that it is collected in a
way, which will preserve (as
closely as possible) its original
condition.
30
Crime Scene
Investigation
Labeling At the time of collection:
- a detailed label should be attached to the package and
include all of the following:
•
•
•
•
•
•
•
•
•
Time & date collected
By whom collected
Type of incident
Description of the item
Location of the incident
Suspect & victims name if known
Location of the item
Name of the Senior CSI & their location
CSIs – names and job number
31
Crime Scene
Investigation
Continuity is maintained by:
• Accurate records (of the scene
and item)
• Detailed labeling, appropriate and
sealed packaging
• Accurate official records and logs
• Secure storage of the item(s)
• Full documentation of any subsequent
movement
• It is preferable that the CSI is the only
link in the chain of custody of an item
32
Crime Scene
Investigation
Interpretation may include:
• Assist in establishing how the
incident occurred
• Prove or disprove witness, suspect
or victims, versions of the incident
• Provide investigators with
information, which may assist with
inquiries and interviewing of
witnesses, victims, and suspects
33
Crime Scene
Investigation
Suitable evidence is used in court.
Interpretation may suggest a theory of
what occurred, based on:
• Observations at the crime or incident
scene
• The physical evidence located
• Information received from the Senior
Investigating Officer e.g. interviews and
subsequent inquiries
• Results of examinations, analyses and
other specialized tests.
34
Crime Scene
Investigation
• The results of interpretation are the
formation of opinions or likely
conclusions
• Interpretation must be thorough and
a reliable report made of the
observations, rather than the
investigator's belief of what
occurred.
35
Crime Scene
Investigation
4 Basic Limitations to the process of
Reconstructing the incident:
1.Quantity and quality of the
information received, physical
evidence present and method of
recording.
2. Ability and expertise of the crime
scene investigator.
3. Extent of interpretation required.
4. Time and financial resources
available.
36
Crime Scene
Investigation
Human Remains and Identification
Notes should include:
• Position of the body
• Description and state of clothing (is it
partially removed, stained, tangled or
twisted?)
• Describe the location, intensity, size, and
direction of flow of any staining if
possible.
• Type of stain (blood-like, semen, dirt,
vomit, feces, urine or some other fluid)
37
Crime Scene
Investigation
• Any visible damage to the clothing
and body
• Description of bloodstains (spots,
spatter or smearing and directionality)
• Appearance of evidence removal (has
the body been washed or blood
cleaned from the body?)
• Estimated amounts of blood (has
staining penetrated layers, carpeting
or other surfaces, is it superficial?)
38
Crime Scene
Investigation
The Recovery Of Human
Remains
1.Outdoor vs. Indoor
2.Decomposition Rates/Temp.
3.Use of Dogs to find bodies
(9/11)
39
Crime Scene
Investigation
Forensic Specialties
Anthropology
• The scientific discipline mainly
concerned with the study of bodily
or skeletal remains.
• DNA, Mitochondrial DNA (family)
• Dr. Michael Baden/[
]
40
Crime Scene
Investigation
Its possible to determine 2 types of
information from remains:
1. Physical characteristics such as
sex, ethnicity, approximate age,
stature, certain disease states and
old injuries
2. The actual identification of the
individual
41
Crime Scene
Investigation
Forensic Odontology
• Uses dental records to help in human
identification, and is often necessary for
the identification of unrecognizable
bodies, after fires or mass disasters, and
in the identification and comparison of
bite marks.
42
Crime Scene
Investigation
Forensic Pathology
Estimating Time of Death
1.Changes in appearance of eyes
2.Cooling of Body Temperature (livor mortis)
3.Rigidity of the body (rigor mortis)
4.Blood pooling in a specific area of the body (algor
mortis)
5.Decomposition or putrefaction is the breakdown of
the body due to autolysis and bacterial
decomposition
6. Insect Infestation and Forensic Entomology
43
Crime Scene
Investigation
Forensic Photography
• Crime scene photographs are permanent
and comprehensive pieces of evidence
that may be presented in court to prove
or disprove facts in question.
44
Crime Scene
Investigation
Blood Splatter Analysis -Bloodstain
Interpretation
• Properly collected and preserved blood
evidence can establish a link between
an individual, a criminal act or a crime
scene
• It is used to strengthen or contradict a
witness or suspects statement or to
eliminate a person as a potential
suspect in a crime.
45
Crime Scene
Investigation
Blood Splatter Analysis Expert
• 1971
• MacDonell (AFIP, Washington, DC)
1. Outlined general rules regarding
blood spatter evidence
2. Outlined general rules of blood
spatter pattern recognition including
spot shape, edge characteristics, spot
diameter, angle of impact, degree of
spatter, directionality, cast off
droplets and high and low velocity
impact stains
46
Crime Scene
Investigation
Collecting Blood Evidence
• Collection and Preservation of Blood
Evidence
1. Dried Bloodstains
2. Wet Bloodstains
• http://www.crime-sceneinvestigator.net/blood.html
47
Crime Scene
Investigation
Wet Blood Stains
• Liquid pools - pick up on gauze pad or other clean,
sterile cotton cloth. Allowed to air dry thoroughly at
room temp. Refrigerate or freeze as soon as possible.
Delays beyond 48 hours may make blood samples
useless.
• Deliver stained object immediately to lab.
• If the object must be mailed, allow the stain to air dry
completely before packaging.
• Do not heat stained material or place it in bright
sunlight to dry. Hang clothing and similar articles in a
room where there is adequate ventilation.
• If not completely dry, label and roll in paper or place
in a brown paper bag or box and seal and label
container. Place only one item in each container. Do
not use plastic containers.
48
Crime Scene
Investigation
Dried Blood Stains
• On clothing, wrap the item in clean paper, place the article in
a brown paper bag or box and seal and label container.
• Small solid objects: send the whole stained object to the Lab.
• Large solid objects: cover the stained area with clean paper
and seal the edges down with tape to prevent loss or
contamination. If impractical to deliver the whole object to
the Lab, scrape the stain onto a clean piece of paper, which
can be folded and placed in an envelope. Scrape blood from
objects using a freshly washed and dried knife or similar tool.
Wash and dry the tool before each stain is scraped off. Seal
and mark the envelope.
• Do not mix dried stains. Place each stain in a separate
envelope.
• Do not attempt to wipe dried stains from an object using a
moistened cloth or paper.
49
Crime Scene
Investigation
Motor Vehicle Investigation
50
Crime Scene
Investigation
Steps of Vehicle Processing
1. Initial examination
2. Written documentation of vehicle in
original state
3. Systematic photographic and
documentation
4. An organized section-by-section
search should be conducted to find
items of evidence not immediately
obvious during the initial exam.
51
Crime Scene
Investigation
5. Other items of evidence located during
the search should be annotated with
evidence markers and photographed to
record location and relationship of any
evidence found
6. Collection of evidence, beginning with
the most fragile evidence (trace
evidence), evidence easily lost, or
susceptible to damage or loss through
handling or weather conditions
52
Crime Scene
Investigation
7. Mechanical processing for any latent
fingerprints.
8. Control samples should be acquired,
including glass samples, fiber samples for
upholstery and carpet, chipped paint, and
wiring for comparison with electronic
components, like CD players and telephones
that may have been stolen from the vehicle.
•
53
Crime Scene
Investigation
Abandoned Vehicles
Types of Evidence to collect:
• Odometer readings
• Gas levels
• Appearance for reason for stopping there
• Damage
• Radiator temperature and ambient
temperature to assist in determining the
time of abandonment
•
54
Crime Scene
Investigation
• Homicide - Vehicular
• Body located in car
• Body removed before car found
55
Crime Scene
Investigation
Hit and Run Investigations
There are two types of scenes to
process:
• Damage to other vehicles or
property
• Death and injury
56
Crime Scene
Investigation
Types of vehicular physical
evidence:
• Identity of the missing vehicle
• Connect the vehicle with the crime
scene or the victim
• Help in reconstructing the events
surrounding the crime
57
Crime Scene
Investigation
Known specimens
from the hit and
run vehicle
• Paint chips
• Headlight and tail
lamp glass
• Bulb filaments
• Headlight lenses
• Signal reflectors
Assoc. vehicle to
crime
• Hairs
• Clothing fibers
• Paint
• Glass
• Blood
• Tissue
58
Crime Scene
Investigation
Vehicle Marks
• Tire impressions
• Wheel marks (used to determine the
direction of vehicle movement)
• Skid marks (provide information on
vehicle speed)
• Soil disturbances
59
Arrival at the
Crime Scene
Upon arrival at a crime scene the 1st
Responder police officer to a crime
scene is responsible for:
1. Acquiring medical assistance for injured
victims
Medical personnel avoid disturbing evidence
and approach the victim by an indirect route.
2. Detaining any potential suspects or
witnesses
Statements are taken from victims,
witnesses, and suspects.
60
Arrival at the
Crime Scene
3. Securing the crime scene to the greatest
extent possible
The boundary is sealed off, and guards are
posted at the entry to the crime scene if
needed.
All civilians and unauthorized personnel are
excluded from the crime scene.
4. Calling for any additional personnel needs
such as other officers and/or forensic
investigators.
The personnel required depends upon the
nature of the crime scene.
61
Securing the
Crime Scene
• The boundaries of the crime scene
must be secured with crime scene
tape, ropes, or cones.
• The secured area should include the
area where the crime took place
and the surrounding area where
physical evidence may be located.
62
Securing the
Crime Scene
• Once the boundaries are secured, guards
may be posted to restrict access to the
crime scene.
• A detailed log is kept of personnel
movements in and out of the crime scene.
This log includes personnel names and
time of entry or exit.
• Investigators should never do anything
that might alter the crime scene including
smoking, eating, drinking, or littering.
63
Surveying the
Crime Scene
The Walkthrough – initial survey of the
crime scene
1. Perpetrator’s point of entry and exit are located.
2. Indirect path is taken to the center of the crime
scene.
3. Obvious items of evidence are located and
documented.
4. The conditions of the scene are observed and
recorded.
Special attention is paid to item or conditions that
suggest timing of the incident or do not appear to
belong.
64
Surveying the
Crime Scene
• Primary Crime Scene
--the location at which the initial crime occurred
Ex: the house in which a murder occurred
• Secondary Crime Scene
--the location at which events after the initial crime
occurred
Ex: the shallow grave in which a murder victim was
buried
• Whether a crime scene is primary or secondary may
be inferred by the presence or absence of specific
evidence.
65
Surveying the
Crime Scene
At the Command Center
1) Investigators receive their assigned
tasks from the lead investigator.
2) Investigators store their equipment.
3) Investigators meet to discuss aspects
of the crime scene.
4) Investigators and law enforcement
personnel communicate with personnel
at other crime scenes.
66
Searching the
Crime Scene
• The search for physical evidence at a
crime scene must be thorough and
systematic.
• The search pattern selected will normally
depend on the size and locale of the scene
and the number of collectors participating
in the search.
• For a factual, unbiased reconstruction of
the crime, the investigator, relying upon
his or her training and experience, must
not overlook any pertinent evidence.
• Physical evidence can be anything from
massive objects to microscopic traces.
67
Searching the
Crime Scene
• Vehicle Searches
-Investigators search interior and exterior of
vehicle.
-The vehicle may be searched at the crime scene
or at the police department or crime laboratory
garage.
• Night Searches
-Investigators avoid carrying out outdoor or dark
indoor crime scene searches at night.
-If possible, the crime scene is secured and
guarded until morning.
68
Crime Scene
Evidence
Forensic science begins at the crime scene.
• If the investigator MUST recognize
physical evidence or MUST properly
preserve it for laboratory examination. NO
sophisticated laboratory instrumentation
or technical expertise can salvage a poorly
investigated crime situation.
• It must be emphasized that the
techniques of crime-scene investigation
are not difficult to master and certainly lie
within the bounds of comprehension of the
average police officer.
Types of Physical
Evidence
• Blood, semen, and
saliva
• Documents
• Drugs
• Explosives
• Fibers
• Fingerprints
• Firearms and
ammunition
• Glass
• Hair
• Impressions
• Organs and
physiological fluids
•
•
•
•
•
•
•
•
•
Paint
Petroleum products
Plastic bags
Plastic, rubber, and
other polymers
Powder residues
Soil and minerals
Tool marks
Vehicle lights
Wood and other
vegetative matter
Procedures for
Collection
• Often, many items of evidence
are clearly visible but others may
be detected only through
examination at the crime
laboratory.
• For this reason, it is important to
collect possible carriers of trace
evidence, such as clothing,
vacuum sweepings, and fingernail
scrapings, in addition to more
discernible items.
Procedures for
Collection
• Investigators must handle and process
physical evidence in a way that prevents
changes to the evidence through
contamination, breakage, evaporation,
accidental scratching or bending, or
through improper or careless packaging.
• The use of latex gloves, disposable
forceps, and sanitized equipment reduces
the chance for contamination.
• Whenever possible, one should keep
evidence in its original condition as found
at the crime scene.
Packaging
• Each different item or similar items
collected at different locations must be
placed in separate containers. Packaging
evidence separately prevents damage
through contact and prevents crosscontamination.
• The well-prepared evidence collector will
arrive at a crime scene with a large
assortment of packaging materials and
tools ready to encounter any type of
situation.
Packaging
• Disposable forceps and similar tools may have to
be used to pick up small items.
• Unbreakable plastic pill bottles with pressure lids
are excellent containers for hairs, glass, fibers,
and various other kinds of small or trace
evidence.
• Alternatively, manila envelopes, screw-cap glass
vials, or cardboard pillboxes are adequate
containers for most trace evidence encountered
at crime sites.
• Ordinary mailing envelopes should not be used
as evidence containers because powders and fine
particles will leak out of their corners.
Packaging
• Small amounts of trace evidence
can also be conveniently packaged
in a carefully folded paper, using
what is known as a “druggist fold.”
• Evidence from arson scenes should
be packaged in airtight metal or
glass containers to prevent the loss
of accelerant vapors.
Packaging
• If biological or bloodstained materials are
stored in airtight containers, the
accumulation of moisture may encourage
the growth of mold, which can destroy the
evidential value.
• In these instances, the material should be
allowed to air-dry before being packaged
in wrapping paper, manila envelopes, or
paper bags.
Packaging
• Contamination is a key concern during the
collection of DNA-containing specimens
such as blood, saliva, sweat or skin cells.
Contamination can occur either by
introducing foreign DNA through coughing
or sneezing onto evidence or if items of
evidence are incorrectly placed in contact
with each other during packaging.
• To prevent contamination, the evidence
collector must wear a face mask and use
disposable latex gloves and disposable
forceps when collecting evidence that may
contain DNA.
Chain of Custody
• Chain of Custody - a list of all persons who came into
possession of an item of evidence.
• Continuity of possession, or the chain of custody, must
be established whenever evidence is presented in court
as an exhibit.
• Adherence to standard procedures in recording the
location of evidence, marking it for identification, and
properly completing evidence submission forms for
laboratory analysis is critical to chain of custody.
• Every person who handled or examined the evidence
and where it was at all times must be accounted for.
Obtaining Reference
Samples
• Standard/Reference Sample—Physical evidence whose
origin is known, such as blood or hair from a suspect,
that can be compared to crime-scene evidence.
• The examination of evidence, whether it is soil, blood,
glass, hair, fibers, and so on, often requires comparison
with a known standard/reference sample.
• Although most investigators have little difficulty
recognizing and collecting relevant crime-scene evidence,
few seem aware of the necessity and importance of
providing the crime lab with a thorough sampling of
standard/reference materials.
Submitting Evidence
• Evidence is usually submitted to the
laboratory either by personal delivery or by
mail shipment.
• Care must be taken in packaging evidence
that will be sent by mail in order to prevent
breakage or other accidental destruction
during transit to the laboratory.
• Most laboratories require that an evidence
submission form accompany all evidence
submitted. Case information provided on
this form enables the laboratory analyst to
make an intelligent and complete
examination of the evidence.
Crime Scene Safety
• Crime scenes frequently present the
investigator with biological specimens of
unknown origin; the investigator has no
way of gauging what health hazards they
may contain.
• Therefore, one must use caution and
protection at all times.
• It is recommended by the International
Association for Identification Safety
Committee that crime scene personnel wear
a minimum of latex gloves (double gloved)
and protective shoe covers. In cases of
large contamination areas, coveralls are
also recommended.
Crime Scene Safety
• The use of a particle mask/respirator,
goggles, or face shield is recommended in
addition to the minimum protective items
when potentially infectious dust or mist are
present.
• Personnel should be alert to sharp objects,
knives, hypodermic syringes, razor blades,
and similar items.
• Personnel should maintain a red biohazard
plastic bag for the disposal of contaminated
gloves, clothing, masks, pencils, wrapping
paper, and so on.
Search and Seizure
Protocols
• The removal of any evidence from a person
or from the scene of a crime must be done
in conformity with Fourth Amendment
privileges: “The right of the people to be secure
in their persons, houses, papers, and effects,
against unreasonable searches and seizure, shall
not be violated, and no warrants shall issue, but
upon probable cause, supported by oath or
affirmation, and particularly describing the place to
be searched, and the persons or things to be
seized.”
Search and Seizure
Protocols
•
The United States Supreme Court has
determined that search and seizure
without a court-approved warrant is
justified in four cases:
1) The existence of emergency circumstances
2) The need to prevent the immediate loss or
destruction of evidence
3) A search of a person and property within the
immediate control of the person provided it is
made incident to a lawful arrest
4) A search made by consent of the parties
involved
Search and Seizure
Landmark Cases
• In the case of Mincey v. Arizona,
the Court dealt with the legality of a
four-day search at a homicide scene
and determined that the evidence
was illegally seized because a
warrant was never issued and the
circumstances of the case did not
justify a warrantless search.
Search and Seizure
Landmark Cases
• In Michigan v. Tyler, fire destroyed
a business establishment leased by
Loren Tyler and a business partner.
The court decided that evidence
obtained from the initial search was
legally seized, but evidence obtained
from searches 4, 7, and 24 days
after the incident were illegally
seized.
Departing the
Crime Scene
• The experienced lead investigator
decides when all pertinent physical
evidence has been recorded and
collected at the crime scene.
• A final survey is undertaken to
visually review the scene and collect
all evidence and equipment.
• Following the final survey, the crime
scene is released to the proper
authorities.
87
5 STEPS OF CRIME
SCENE PROCESSING
1. Responding to the crime scene
requires the CSI to arrive with a
plan and the proper attitude. The
CSI must communicate with the 1st
Responding officers and learn as
much as possible about what has
taken place. Scene perimeters are
established or enlarged and the
scene is secured.
88
5 STEPS OF CRIME
SCENE PROCESSING
2. Crime scene photography is next.
This step must be completed prior
to moving or collecting any
evidence.
3. Crime scene diagramming. The
rough sketch with measurements
must be completed prior to moving
anything and a complete evidence
list and sketch legend is completed.
89
5 STEPS OF CRIME
SCENE PROCESSING
4. Collection of physical evidence.
The scene must be legally searched
for evidence that is both seen and
unseen. When evidence is found, it
must be documented fully, collected
properly and packaged in such a way
to maintain its evidentiary value.
90
5 STEPS OF CRIME
SCENE PROCESSING
5. Processing the scene for fingerprints.
Fingerprinting the crime scene is usually
performed last because fingerprint
powders will contaminate the scene.
Those items or surfaces that need
processing will have to be protected from
contamination until after the scene has
been processed. There are exceptions to
this which are determined by the
circumstances of each scene.
91
5 STEPS OF CRIME
SCENE PROCESSING
• Processing a crime scene might take a few
hours to several days. While processing the
scene, you will have to make numerous
decisions that will eventually be scrutinized
by teams of lawyers and experts in various
forensic disciplines. The lawyers and forensic
experts have months and sometimes years
to pull your work apart. Your work, based on
your decisions, must be able to stand up to
these numerous challenges.
92
CRIME SCENE
DETECTIVE QUALITIES
3 qualities of a CSI: to be successful processing crime
scenes:
1. Attitude - First, and most important, the crime scene
detective must have the proper attitude or he/she will
be defeated before starting. Crime scene work is very
demanding both mentally and physically because the
majority of evidence at major crime scenes is often
hidden. Searching a scene for fingerprint evidence,
trace evidence and processing a deceased body are
extremely time consuming tasks and are often
performed in confined spaces and awkward positions.
It can be very easy to justify overlooking some of the
processing techniques required for the successful
recovery of evidence.
93
CRIME SCENE
DETECTIVE QUALITIES
2. Training - The crime scene detective must
continue to train. Training will provide the
detective with guidance and the ability to
better understand a crime scene. Training,
however, is nothing without the proper
attitude. The crime scene detective must be
able to use the proper procedure at the
proper time or the training was wasted.
94
CRIME SCENE
DETECTIVE QUALITIES
3. Experience - The crime scene detective must
have experience. Without experience, the
detective may be overwhelmed at major crime
scenes and evidence might be missed. The CSI
should use property crimes such as burglaries
to train for the more serious crimes against
persons. The focus of a CSI should always be
toward the homicide scene, the ultimate major
crime.
95
CRIME SCENE
DETECTIVE QUALITIES
Nothing can replace experience; however,
continued training can prepare you to
respond and react the way you have
trained.
IT ALL STARTS
WITH YOUR
ATTITUDE!
96
Crime Scene
Notes
• Note taking begins when the investigator is
contacted & requested to report to the
crime scene.
• Crime scene notes should begin with:
1.The identity of person who contacted the
investigator
2. Time of contact and arrival at the crime scene
3. Preliminary case information
4. Personnel present on arrival and those being
contacted
97
Crime Scene
Notes
• Notes contain a personnel log, all
observations made by the investigator,
and the time observations were made.
• Notes are taken in a uniform layout,
concurrently as the observations are
made.
• Notes are written in a bound notebook
in blue or black ink.
98
Crime Scene
Notes
Investigators may choose to record
crime scene notes on audio tapes.
• This leaves the hands free to process
the scene as the notes are taken.
• Tape-recorded notes must eventually
be transcribed to a written
document.
99