Crime Scene Investigation: Offense Investigations

Objectives of a Criminal Investigation

• List the basic types of bombs
• Identify statutes pertaining to arson and explosives
• Identify the patrol officer's role in responding to a bomb threat
• State who should conduct a search of a facility for a device after a bomb threat

Types of Bombs

• Explosive Bomb: a device that causes damage by fragmentation, heat, and blast wave, often producing a fire
• Incendiary Bomb: a device constructed with flammable materials designed to produce a burning effect

Laws Pertaining to Arson and Explosives

• Arson (Class A, B, or C Felony): knowingly damaging a building or inhabitable structure by starting a fire or causing an explosion
• Knowingly burning or exploding (Class "D" Felony): knowingly damaging property of another by starting a fire or causing an explosion
• Reckless burning or exploding (Class "A" Misdemeanor): recklessly damaging or destroying a building or inhabitable structure of another by knowingly starting a fire or causing an explosion
• Negligent burning or exploding (Class "B" Misdemeanor): with criminal negligence causing damage to property of another by fire or explosion
• Causing catastrophe (Class "A" Felony): knowingly causing death or serious physical injury to ten or more people, or substantial damage to five or more buildings or inhabitable structures
• Possession, manufacture, transport, repair, or sale of certain weapons prohibited (Class "C" Felony): knowingly possessing, manufacturing, transporting, repairing, or selling an explosive
• Bombing and other explosive matter upon bus or near bus terminal (Class "A" Felony): to bomb or to plant or place any bomb or other explosive matter upon or near any terminal or bus
• False Bomb Report (Class "A" Misdemeanor): knowingly making or causing to be made a false report to any person that a bomb or other explosive has been placed in a public or private place or vehicle

Bomb Threat Response Procedures

• Turn radio off when nearing scene to avoid detonating an explosive device
• Contact manager/person in charge to inform them of the situation and let them decide whether to evacuate the building
• Building search should be conducted by personnel who are most familiar with the premises
• Evacuation should be done if an explosive device or suspected device is found
• Evacuate everyone, be aware of the possibility of a second device, and post guards at entrances
• Evacuation distances depend on the size of the explosive device
• Secure a perimeter of 300 feet for unknown sized devices

Bombing Scene Procedures

• Establish a perimeter by locating the furthest piece of debris from the blast seat and measuring the distance from that debris to the blast seat
• Limit admittance to scene to paramedics, arson and explosive detectives, and crime scene technicians
• Use one entry/exit path to minimize the chance of destroying fragile evidence
• Be cautious and aware of secondary devices while securing the perimeter

Elementary Chemistry of Fire

• Burning requires four elements: heat, oxygen, fuel, and uninhibited chain reaction
• Heat is transferred through conduction, convection, and radiation
• Phases of structural fires include:
  • Incipient (first phase): fire produces gases, rapid progress after flaming starts
  • Free burning/flame producing (second phase): major involvement, convection heating, large amount of dark gray smoke
  • Smoldering (third phase): burning is reduced to glowing embers, large quantity of toxic/flammable gases, back draft possibility