CFI Surveillance Methods & Technology 3 — Questions and Answers
Question 1: A cell phone tower records showing a suspect's device pinging near a fire scene are BEST described as what type of evidence?
- Demonstrative evidence
- Physical evidence
- Digital circumstantial evidence (Correct answer)
- Hearsay evidence
Correct answer: Digital circumstantial evidence
Cell tower location records are digital circumstantial evidence that can corroborate or contradict a suspect's stated location without directly proving guilt.
Question 2: When preserving DVR evidence at a fire scene, the chain of custody requires the investigator to:
- Copy the footage to any available USB drive immediately
- Document the device serial number, date, time, and all persons handling it (Correct answer)
- Erase footage after copying to prevent tampering
- Return the DVR to the owner after copying
Correct answer: Document the device serial number, date, time, and all persons handling it
A proper chain of custody requires meticulous documentation of every person who handles evidence and all associated identifying information.
Question 3: Which surveillance technique involves analyzing the pattern of false alarms prior to a fire to identify potential arson pre-planning?
- Aerial surveillance
- Temporal pattern analysis (Correct answer)
- Thermal imaging review
- Perimeter monitoring
Correct answer: Temporal pattern analysis
Temporal pattern analysis of alarm histories can reveal rehearsal behavior or deliberate testing of detection systems by an arsonist.
Question 4: Automated License Plate Recognition (ALPR) data collected near a fire scene is obtained through:
- Voluntary disclosure by private parking operators only
- Law enforcement databases, private networks, or subpoena of commercial systems (Correct answer)
- Direct download from vehicle onboard computers
- Satellite image analysis
Correct answer: Law enforcement databases, private networks, or subpoena of commercial systems
ALPR data may be accessed through police databases, private parking or tolling networks, or legal process such as subpoenas served on commercial operators.
Question 5: A fire investigator reviewing ATM camera footage notes the image is distorted near the edges. This is MOST likely caused by:
- Infrared filter degradation
- Wide-angle or fisheye lens barrel distortion (Correct answer)
- Insufficient frame rate
- Incorrect white balance settings
Correct answer: Wide-angle or fisheye lens barrel distortion
Wide-angle and fisheye lenses commonly used in ATM cameras introduce barrel distortion that curves straight lines near image edges.
Question 6: In fire investigation surveillance, the term 'canvass' refers to:
- Aerial photography of the burn area
- Systematic contact with area residents and businesses to locate witnesses and footage (Correct answer)
- Deployment of surveillance cameras around the perimeter
- Laboratory analysis of smoke patterns
Correct answer: Systematic contact with area residents and businesses to locate witnesses and footage
A canvass involves systematically interviewing nearby residents, businesses, and visitors to locate eyewitnesses and uncover available surveillance footage.
Question 7: What phenomenon can cause a surveillance camera's recorded time to drift significantly from actual time over months of operation?
- Video compression artifacts
- Network latency spikes
- Internal clock drift without NTP synchronization (Correct answer)
- Lens focal length changes
Correct answer: Internal clock drift without NTP synchronization
Without synchronization to a Network Time Protocol server, a camera's internal clock can accumulate significant drift, undermining the evidentiary value of timestamps.
CFI Surveillance Methods & Technology 3
A cell phone tower records showing a suspect's device pinging near a fire scene are BEST described as what type of evidence?