Essentials of Fire Fighting,
5th Edition
Chapter 18 — Protecting Fire
Scene Evidence
Firefighter II
Chapter 18 Lesson Goal
• After completing this lesson, the
student shall be able to assist in the
investigation of a suspicious fire and
protect and preserve evidence after a
fire following the policies and
procedures set forth by the authority
having jurisdiction (AHJ).
Firefighter II
18–1
Specific Objectives
1. Discuss the roles of firefighters and
investigators at investigations.
2. Summarize important observations to
be made en route, after arriving at
the scene, and during fire fighting
operations.
3. Discuss firefighter conduct and
(Continued)
statements at the scene.
Firefighter II
18–2
Specific Objectives
4. Explain firefighter responsibilities after
the fire.
5. Explain how legal considerations affect
firefighters during operations that
may involve incendiary evidence.
(Continued)
Firefighter II
18–3
Specific Objectives
6. Discuss protecting and preserving
evidence.
7. Protect evidence of fire cause and
origin. (Skill Sheet 18-II-1)
Firefighter II
18–4
Roles at an Investigation:
General Considerations
• Determining the cause of a fire may
only require the expertise of the
emergency responders on scene
(Continued)
Firefighter II
18–5
Roles at an Investigation:
General Considerations
• More complex fire
incidents or possible
crime scenes often
require assistance of
law enforcement
personnel and qualified
fire investigators
Courtesy of Sheldon Levi, IFPA.
(Continued)
Firefighter II
18–6
Roles at an Investigation:
General Considerations
• Guidelines for initiating steps vary
among jurisdictions and the nature of
the incident
• Firefighters must be aware of the
guidelines and/or regulations in their
areas
Firefighter II
18–7
Roles at an Investigation:
Firefighter Responsibilities
• In most jurisdictions, fire chief has the
legal responsibility for determining the
cause and origin
• Fire chief delegates this authority to
fire officers and firefighters at the
scene
(Continued)
Firefighter II
18–8
Roles at an Investigation:
Firefighter Responsibilities
• Proper training enables firefighters to
recognize and collect important
information
• First-arriving firefighters can observe
unusual conditions that may indicate an
incendiary fire
Firefighter II
18–9
Roles at an Investigation:
Investigator Responsibilities
• Fire marshals or others
may be responsible for
conducting investigations
beyond the determination
of fire origin and cause
(Continued)
Firefighter II
18–10
Roles at an Investigation:
Investigator Responsibilities
• Fire investigators may also be sworn
peace officers
• Firefighters may be questioned by an
investigator or asked to assist in an
investigation
(Continued)
Firefighter II
18–11
Roles at an Investigation:
Investigator Responsibilities
• Some fire departments have special
fire investigation or arson squads
• Arson investigation
– Police department
– State fire marshal or some other state
agency
– Private companies may conduct separate
investigations
(Continued)
Firefighter II
18–12
Observations En Route
• Time of day
• Weather and natural
hazards
• Barriers
• People leaving the
scene
Firefighter II
18–13
Observations Upon Arrival
• Time of arrival and extent
of fire
• Wind direction and
velocity
• Doors or windows locked
or unlocked
• Location of the fire
(Continued)
Firefighter II
18–14
Observations Upon Arrival
• Containers or cans
• Burglary tools
• Familiar faces
Firefighter II
18–15
Observations During Fire
Fighting Operations
• Unusual odors
• Abnormal behavior of
fire when water is
applied
• Obstacles hindering
fire fighting
(Continued)
Firefighter II
18–16
Observations During Fire
Fighting Operations
•
•
•
•
Incendiary devices
Trailers
Structural alterations
Fire patterns
(Continued)
Firefighter II
18–17
Observations During Fire
Fighting Operations
• Heat intensity
• Availability of documents
• Fire detection and
protection systems
• Intrusion alarms
• Location of fire
(Continued)
Firefighter II
18–18
Observations During Fire
Fighting Operations
•
•
•
•
Personal possessions
Household items
Equipment or inventory
Business records
Firefighter II
18–19
Conduct and Statements at the
Scene
• Firefighters should obtain as much
information as possible
• Owners or occupants of the property
should be allowed to talk freely
(Continued)
Firefighter II
18–20
Conduct and Statements at the
Scene
• Firefighters should not attempt to
interrogate a potential arson suspect
unless trained and authorized
• Firefighters should refrain from
expressing personal opinions
(Continued)
Firefighter II
18–21
Conduct and Statements at the
Scene
• After the investigator arrives,
firefighters should make statements
only to this individual
(Continued)
Firefighter II
18–22
Conduct and Statements at the
Scene
• Public statement regarding fire cause
should be made only after
– The investigator and ranking fire officer
have agreed to its accuracy and validity
– Have given permission for it to be released
Firefighter II
18–23
Responsibilities After the Fire
• Firefighters should report their
observations to their supervisor
• Firefighters should not discuss their
observations with other crew members
• Improperly done overhaul operations
can be detrimental to the investigation
Firefighter II
18–24
Securing the Fire Scene
• Fire department has the authority to
deny access to any building
– During fire fighting operations
– For a reasonable length of time after fire
suppression is terminated
(Continued)
Firefighter II
18–25
Securing the Fire Scene
• If an investigator is
not immediately
available, the fire
department or other
lawful authority
should keep control
of the premises until
all evidence has
been collected
Firefighter II
18–26
(Continued)
Securing the Fire Scene
• Once all fire personnel leave the
scene, a search warrant or written
consent to search will be required to
reenter the premises
(Continued)
Firefighter II
18–27
Securing the Fire Scene
• Fire personnel should not allow
anyone to enter a fire scene without
the investigator’s permission
• The premises can be secured and
protected in several ways
(Continued)
Firefighter II
18–28
Securing the Fire Scene
• Cordoning can be accomplished with
rope or specially designed fire and
police line tape
Firefighter II
18–29
Legal Considerations
• Legal cases
– Firefighters may remain on location as long
as necessary, but once they leave they
may be required to get a search warrant
– Based on the case of Michigan vs. Tyler
– U.S. Supreme Court findings
(Continued)
Firefighter II
18–30
Legal Considerations
• Impact on firefighters
– If there is incendiary evidence, fire
department should leave at least one
person on premises until an investigator
arrives
– To leave the premises, return later without
a search warrant, and make a search might
have negative consequences
(Continued)
Firefighter II
18–31
Legal Considerations
• Impact on firefighters (cont.)
– Each department must comply with the
legal opinions that affect its jurisdiction
Firefighter II
18–32
Protecting and Preserving
Evidence
• Protect evidence by keeping it
untouched and undisturbed until an
investigator arrives
• Do not gather or handle evidence
unless it is absolutely necessary in order
to preserve it
(Continued)
Firefighter II
18–33
Protecting and Preserving
Evidence
• If firefighters handle or procure
evidence, they then become a link in
the chain of custody for that evidence
• Evidence must remain undisturbed
except when absolutely necessary for
the extinguishment of the fire
(Continued)
Firefighter II
18–34
Protecting and Preserving
Evidence
• Firefighters must avoid trampling over
possible evidence and obliterating it
• The same precaution applied to the
excessive use of water may help avoid
similar unsatisfactory results
(Continued)
Firefighter II
18–35
Protecting and Preserving
Evidence
• Human footprints and
tire marks must be
protected; use
cardboard boxes
(Continued)
Firefighter II
18–36
Protecting and Preserving
Evidence
• Protect completely or partially burned
papers found in a furnace, stove, or
fireplace by immediately closing
dampers and other openings
• Leave charred documents found in
containers
(Continued)
Firefighter II
18–37
After Evidence Has Been
Collected
• After evidence has been properly
collected by an investigator, debris may
be removed
• Remove charred materials to prevent
the possibility of rekindle and to help
reduce smoke damage
(Continued)
Firefighter II
18–38
After Evidence Has Been
Collected
• Unburned materials can be separated
from the debris and cleaned
Firefighter II
18–39
Summary
• Before an investigation into the origin
and cause of a fire can be conducted,
there must be evidence to evaluate.
(Continued)
Firefighter II
18–40
Summary
• As a firefighter, one of the most
important responsibilities is to avoid
disturbing or destroying evidence while
fighting the fire. In the area of origin
appropriate caution must be used when
spraying water, moving debris, and
even walking around.
(Continued)
Firefighter II
18–41
Summary
• Once the area of origin is known, a
more thorough investigation can be
conducted to determine the exact cause
of the fire.
(Continued)
Firefighter II
18–42
Summary
• As a firefighter, it may be necessary to
determine the cause of the fire; more
likely, firefighters may be assigned to
assist their supervisor or a fire
investigator in making that
determination.
(Continued)
Firefighter II
18–43
Summary
• If the fire origin and cause investigation
reveals evidence of arson, the property
becomes a crime scene and must be
treated as one. Firefighters must
cooperate fully with whoever is
assigned to investigate the crime.
Firefighter II
18–44
Review Questions
1. What individuals may have
responsibilities in a fire investigation?
2. What are some observations that may
indicate a fire was incendiary?
3. What is one way that a fire scene can
be secured?
(Continued)
Firefighter II
18–45
Review Questions
4. Why should the fire department leave
at least one person on the premises
of a scene until the investigator
arrives?
5. What are ways that evidence can be
protected?
Firefighter II
18–46