OIC Evidence Collection & Preservation 3 — Questions and Answers
Question 1: What does the term 'spoliation of evidence' mean in the context of fire investigation?
- The natural decay of evidence over time due to weather
- The intentional or negligent destruction or alteration of evidence that may be needed in litigation (Correct answer)
- The proper disposal of non-evidentiary debris after investigation
- The transfer of evidence to a secondary laboratory
Correct answer: The intentional or negligent destruction or alteration of evidence that may be needed in litigation
Spoliation refers to destroying or altering evidence that could be relevant to litigation, which can result in legal sanctions against the responsible party.
Question 2: Which of the following best describes the 'locard exchange principle' as applied to fire investigation?
- Fire always leaves trace evidence of its ignition source at the point of origin
- Every contact between a person and a scene results in an exchange of trace materials (Correct answer)
- Accelerants evaporate completely, leaving no recoverable evidence
- Documentation must be exchanged between all agencies on scene
Correct answer: Every contact between a person and a scene results in an exchange of trace materials
Locard's principle states that any contact between two objects results in material transfer, meaning perpetrators leave trace evidence and take some away.
Question 3: A fire investigator needs to collect a flooring sample suspected of containing accelerant residue. How large should the sample generally be?
- As large as possible, at least 1 square foot
- A minimum sample of approximately 1 pint volume or about 500 grams of material (Correct answer)
- Only a surface scraping of a few grams is needed
- Sample size does not matter as long as the container is sealed
Correct answer: A minimum sample of approximately 1 pint volume or about 500 grams of material
NFPA 921 recommends collecting approximately one pint or 500 grams of material to provide the lab with sufficient quantity for analysis.
Question 4: When documenting evidence with video at a fire scene, what practice is most important?
- Record only after all photos have been taken
- Provide a continuous narrated walkthrough to establish spatial context (Correct answer)
- Avoid narrating to prevent audio from being used in court
- Focus the video exclusively on the point of origin
Correct answer: Provide a continuous narrated walkthrough to establish spatial context
A narrated video walkthrough establishes spatial relationships and scene context in a way that still photos alone cannot capture.
Question 5: What information must appear on the evidence label attached to a collected sample container?
- Only the case number and investigator name
- Case number, sample description, location collected, date/time, and collector's name (Correct answer)
- Date of the fire and property owner's name only
- Insurance policy number and claim amount
Correct answer: Case number, sample description, location collected, date/time, and collector's name
A complete evidence label must include all identifying details—case number, description, collection location, date, time, and collector—to support chain of custody.
Question 6: In Oregon arson investigations, who typically has the authority to issue a search warrant for a privately owned fire scene after the emergency phase has ended?
- The fire chief at the scene
- A licensed contractor assessing damage
- A magistrate or judge upon showing of probable cause (Correct answer)
- The insurance company's SIU investigator
Correct answer: A magistrate or judge upon showing of probable cause
After the emergency phase, investigators must obtain a warrant from a magistrate or judge, demonstrating probable cause that evidence of a crime will be found.
Question 7: How should an investigator handle a piece of electrical equipment suspected as the fire's ignition source?
- Test it by plugging it in to verify if it functions
- Photograph it in place, then carefully package it to prevent further damage during transport (Correct answer)
- Disassemble it on scene to look for internal faults before packaging
- Leave it in place and note its location without collecting it
Correct answer: Photograph it in place, then carefully package it to prevent further damage during transport
Suspected ignition devices must be photographed in place and packaged carefully to preserve their condition for later laboratory examination by a qualified expert.
OIC Evidence Collection & Preservation 3
What does the term 'spoliation of evidence' mean in the context of fire investigation?