The Burning Question:Is it Arson?

How can we make fire?

• Heat + Fuel + Oxygen

How can we make fire?

• Oxidation: combination of oxygen with other substances to produce new substances

• Combustion: oxidation reaction with the rapid combination of oxygen with another substance accompanied by the production of heat and light

How can we make fire?

• Flash Point: Lowest temperature at which a liquid gives off sufficient vapor to form a mixture with air that will support combustion (gasoline -50oF)

How can we make fire?

• Ignition Temperature: The high temperature that is required to “jump start” the reaction between oxygen and a reactant (gasoline 495of)

Was it arson?

• Fires can be caused: • Naturally• Accidentally• Intentionally

Was it arson?

• Suspect arson if you find:• Accelerants

• Paper, black powder, kindling wood, gasoline, kerosene, alcohols, paint thinners, natural gas, propane, lighter fluid

• Incendiary Devices• Timing devices, initiators, candles,

electronic timers

What is arson?

• Sniffer/Arson Dogs• Chemical Detectors (Vapor Trace

Analyzer-VTA) screens air for accelerant residues

Where did the fire start?

• Find the point of origin (POO)• Fire spreads upward and sideways

from the POO• V-pattern

Where did the fire start?• POO has the most damage• Location of igniters and

accelerants• Stairwells & Drafts may pull the

fire in one direction• Smoke detector• Doors & Floors

Where did the fire start?

How is arson evidence collected & packaged?• Package ASAP in nonporous,

sealed containers (clean paint cans, glass jars)• Effect of water on evidence

• Collect samples from area of fire and from unburned areas to compare

• Collect suspect’s clothing

What do we do with arson evidence?

• Extract any possible accelerants from debris

• Ultra Violet (UV) Spectroscopy• Gas Chromatography (GC) - Mass

Spectroscopy (MS)• Infrared Spectrophotometry (IR)

UV Spec

GC-MS Spec

IR Spec for Gasoline

Can we tell when the victim died?• Position body was in

• Burning corpse assumes boxer’s position • Carbon monoxide levels in blood and

tissue• Asphyxia (suffocation) from inhaling smoke

and carbon monoxide (CO) • CO Intoxication – excessive CO in the

bloodstream• Toxicity of CO may prevent victim from escaping

even if there is enough time• Bright cherry red blood

• Soot in the mouth, throat, lungs, and airways

Why arson?

• Covering their tracks • Insurance fraud• Psychological reasons• Revenge• Suicide or murder• Terrorism

Arson Statistics

• The US has the highest rate of arson in the world

• One of the fastest growing crimes• $1.5 billion in property loss/year• 55% of all arson arrests are

children under 18 yoa

Arson Statistics

• Leading cause of fires• 50% of arson cases occur

outdoors, 30% in structures, 20% in vehicles

• Cooking fires are the leading cause of fire-related injury, and smoking fires are the leading cause of fire deaths

Arson & The Law

• Felony Arson – Up to $25,000 fine &/or 3-7 years in jail

• Aggravated Arson (Felony) - Up to $25,000 fine &/or 6-30 years in jail

• Residential Arson (Felony) - Up to $25,000 fine &/or 4-15 years in jail

Who are arsonistis?

• Gender• Race• Age• # Fires set• History with law• Intelligence• Education• Psychological history

Who are arsonistis?

• Family/Relationships• Hobbies• Occupation• Post-fire activity• Ego

Who are arsonists?

• Organized• Elaborate incendiary devices, less

physical evidence, methodical

• Disorganized• Uses materials at hand, more physical

evidence is left