CFI Evidence Collection & Chain of Custody 3 — Questions and Answers
Question 1: When collecting charred wood samples suspected to contain accelerants, which layer should be prioritized for collection?
- The outermost charred surface layer
- The interface between burned and unburned material (Correct answer)
- The center of the burned wood
- Only ash residue from the surface
Correct answer: The interface between burned and unburned material
The interface between burned and unburned material is most likely to retain trapped accelerant residues protected from complete combustion.
Question 2: A fire investigator collects evidence from multiple locations within a scene. How should containers be labeled to maintain proper documentation?
- Only the date of collection is needed
- Containers need only a sequential number
- Each container must include case number, location description, date, time, and collector's initials (Correct answer)
- Labels can be added in the laboratory after analysis
Correct answer: Each container must include case number, location description, date, time, and collector's initials
Every evidence container must be labeled at the time of collection with identifying information linking it to a specific location and collector.
Question 3: Which technique is used to document the exact location of evidence within a fire scene before collection?
- Triangulation measurements from fixed reference points (Correct answer)
- GPS coordinates alone
- Witness statements about where the item was found
- The investigator's memory and verbal notes
Correct answer: Triangulation measurements from fixed reference points
Triangulation from fixed reference points provides precise, reproducible location data that can be verified independently and used in court.
Question 4: What is the significance of 'spoliation' in fire investigation evidence management?
- The natural weathering of evidence left outdoors
- The intentional or negligent destruction of evidence that may be needed in litigation (Correct answer)
- A method of preserving biological evidence through refrigeration
- The process of cataloguing evidence at the laboratory
Correct answer: The intentional or negligent destruction of evidence that may be needed in litigation
Spoliation refers to the destruction or material alteration of evidence, which can lead to legal sanctions and adverse inferences against the responsible party.
Question 5: When multiple agencies (fire department, police, ATF) are all collecting evidence at the same fire scene, which practice best protects the chain of custody?
- Each agency operates independently with its own numbering system
- A unified command evidence coordinator tracks all items with a single log (Correct answer)
- Evidence is pooled at the scene and divided later
- The first agency on scene controls all evidence collection
Correct answer: A unified command evidence coordinator tracks all items with a single log
A unified evidence coordinator with a single master log prevents duplicate numbering, gaps, and confusion over custody when multiple agencies share a scene.
Question 6: A witness hands a fire investigator a cigarette lighter they found near the origin before the investigator arrives. What is the most critical first action?
- Submit the lighter directly to the lab
- Document who had possession of the item and how it was handled before transfer (Correct answer)
- Photograph the lighter immediately and add it to the evidence log
- Refuse to accept the item because the chain of custody is already compromised
Correct answer: Document who had possession of the item and how it was handled before transfer
When evidence has pre-investigation handling, the investigator must document the prior custody to account for any gaps before formal collection begins.
Question 7: For biological evidence found at a fire scene (e.g., blood, tissue), what storage condition is essential?
- Room temperature in sealed plastic bags
- Refrigeration or freezing after packaging in breathable paper or cotton swabs (Correct answer)
- Submerging in a preservative solution
- Storage in the same container as debris samples to save space
Correct answer: Refrigeration or freezing after packaging in breathable paper or cotton swabs
Biological evidence must be stored cold in breathable packaging to prevent bacterial degradation and DNA deterioration.
CFI Evidence Collection & Chain of Custody 3
When collecting charred wood samples suspected to contain accelerants, which layer should be prioritized for collection?