Chapter 16

Arson, Bombs and Explosives

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Introduction• Arson, the malicious, willful burning of a building or

property, is one of the oldest crimes known• Arson is difficult to prove • Police investigators partner with fire investigators to

handle these crimes• Fire marshals, who also have law enforcement powers

for fire-related incidents, investigate these crimes

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CATEGORIES• Natural• Accidental• Incendiary (arson)• Undetermined origin

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Classification of Fires

ELEMENTS• Willful, malicious burning of a building or property• Of another or of one’s own to defraud• Causing to be burned, or aiding, counseling or

procuring such burning

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Elements of the Crime: Arson

AGGRAVATED AND SIMPLE ARSON• Aggravated arson

Intentionally destroying or damaging Fire or explosives or other infernal device Imminent danger to life or great bodily harm

• Simple arson Intentional destruction by fire or explosives Does not create imminent danger to life

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Classification of Arson

ATTEMPTED ARSON• Intent to set a fire • Some preparation to commit the crime

SETTING NEGLIGENT FIRES• Causing a fire to burn • Causing a fire to get out of control

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Classification of Arson

THE MODEL ARSON LAW• First degree: Burning of dwellings• Second degree: Burning of buildings other than

dwellings• Third degree: Burning of other property• Fourth degree: Attempting to burn buildings or

property

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Classification of Arson

JUVENILE FIRESETTING• Children are predominant victims• Fireplay versus firesetting

MOTIVATION• Revenge most common motive• Insurance fraud

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The Arsonist

EXPERTISE• Fire department

Detect arson Determine point of origin Probable cause

• Police department Investigate arson Prepare the case for prosecution

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Police and Fire Department Cooperation

ADDITIONAL RESOURCES• Bureau of Alcohol, Tobacco, Firearms and Explosives• News media• Insurance companies• Arson task forces• Importance of the dispatcher

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Other Sources of Assistance inInvestigating Arson

DIFFICULTIES• Coordinating efforts with fire department and others• Determining whether a crime has been committed• Finding physical evidence• Finding witnesses• Determining whether the victim is a suspect

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Special Challenges in Investigation

OBSERVATIONS• Presence of victims and witnesses• Vehicles leaving the scene• Flame and smoke conditions• Conditions surrounding the scene• Status of alarms and sprinklers

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Responding to the Scene

OVERVIEW• Fire department usually receives the initial call• Fire personnel make out the report• Fire department establishes arson• Investigators must verify fire department findings• Understand distinctions for proving crime

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The Preliminary Investigation

FIRE TRIANGLE• Arson will present an

abnormal amount of Air Fuel Heat

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The Preliminary Investigation

ARSON INDICATORS• Accelerants• Igniters• Burn indicators• Point of origin• Burning pattern• Appearance of collapsed walls and smoke color

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The Preliminary Investigation

SUMMARY OF ARSON INDICATORS• Professionals use various igniters

Magnesium rods, timed charge, acids

PHOTOGRAPHING AND VIDEOTAPING AN ARSON FIRE

• In-progress photographs• People at the fire scene

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The Preliminary Investigation

PHYSICAL EVIDENCE• Very fragile• Identify accelerants (GF-FID)

USING K-9s IN ARSON INVESTIGATIONS• Lab-certified accelerant-detection canine • Accelerants and suspects

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The Preliminary Investigation

EVIDENCE ON SUSPECT, AT RESIDENCE OR IN VEHICLE• Unique odors• Insurance documents

OBSERVING UNUSUALCIRCUMSTANCES

• Alterations to area• Providing more air, heat or fuel

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The Preliminary Investigation

INTERVIEWING• Who had opportunity• Who benefits from it• Victim’s financial status• Cooperation level• First-in firefighters

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The Preliminary Investigation

TYPES• Administrative

Government agent needed to search the premises Determine the fire’s cause and origin

• Criminal• Issued on probable cause • Premises yield evidence of a crime

• Michigan v. Tyler (1978)

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Search Warrants and Fire Investigations

FINAL TIPS• Obtain consent or a warrant• Turn off utilities• Inspect and ventilate• Bring a partner• Wear proper safety gear• Avoid cross contamination

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Final Safety and Legal Considerations

DETERMINATIONS• Look for evidence of accelerants • Determine whether the vehicle was insured• Seldom arson if there was no insurance• Intent to defraud

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Investigating Vehicle Arson

DIFFICULTIES• 90 percent of arsonists go unpunished• Often committed without witnesses• Interagency cooperation required• Circumstantial evidence

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Prosecuting Arsonists

KEY FACTORS• Abandoned properties• Negative-equity properties• Utilities were shut off• Prior-year fires• Gang locales• Drug hot spots

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Preventing Arson

CLASSES• Juvenile/experimentation• Recovered military ordnance or commercial explosives• Emotionally disturbed persons• Criminal actions• Terrorist or extremist activity

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Investigating Bombings and Explosions

OVERVIEW• Nonchalant attitude could

prove fatal• Do not touch the package• Using K-9s in detecting• Stationary technology

Sniffer

• Using robots

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Responding to a Bomb Threat

OVERVIEW• Special attention to fragments of device• Pay attention to powder at the scene• Determine motive• Determine scene parameters

AWARENESS TRAINING AND TEAM APPROACH• Available training programs

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Bomb Scene Investigation

Summary• Fires are natural or accidental unless proven otherwise• Special challenges in investigating arson include

coordinating efforts • Fire department is responsible for establishing whether

arson has occurred• Law enforcement investigators must be able to verify

such findings• When investigating vehicle fires, look for evidence of

accelerants

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