CFL Crime Scene Investigation Procedures 2 — Questions and Answers
Question 1: What is 'chain of custody' and why is it critical for a CFL's forensic work?
- The documented trail showing who handled evidence, ensuring it was not tampered with or contaminated (Correct answer)
- A list of approved lock brands certified for high-security government applications
- The sequential order of keys that operate a master key system hierarchy
- Documentation of which licensed locksmiths previously serviced a specific door
Correct answer: The documented trail showing who handled evidence, ensuring it was not tampered with or contaminated
Chain of custody documents every person who handled evidence, maintaining its integrity and admissibility in legal proceedings by proving it was not tampered with.
Question 2: When a CFL collects metal filings from below a drilled lock, how should these be packaged?
- In a sealed paper envelope or rigid pill box with evidence tape and proper case labeling (Correct answer)
- In a plastic bag with a damp paper towel to prevent electrostatic dispersion
- Taped directly onto the examination worksheet next to the diagram
- Combined with other physical evidence in a single large evidence bag for efficiency
Correct answer: In a sealed paper envelope or rigid pill box with evidence tape and proper case labeling
Metal filings are best preserved in paper envelopes or rigid containers that prevent static buildup and allow residual moisture to escape without losing material.
Question 3: What is the forensic significance of finding brass shavings on a floor directly below a lock?
- It indicates drilling of a brass cylinder, providing physical evidence of destructive bypass (Correct answer)
- It means the lock was recently installed and the installer was careless with debris
- Brass shavings are always present under door hardware due to normal wear
- It indicates the lock body is counterfeit and not made of genuine brass alloy
Correct answer: It indicates drilling of a brass cylinder, providing physical evidence of destructive bypass
Brass shavings below a lock are physical evidence of drilling into a brass cylinder, identifying forced mechanical bypass as the entry method.
Question 4: If a CFL discovers a padlock with shackle marks consistent with bolt cutters, where should forensic documentation be focused?
- The cut face of the shackle, noting the angle, tool width impression, and any transferred metal (Correct answer)
- Only the lock body and internal cylinder mechanism
- The hasp or staple the padlock was mounted to
- The floor surface directly beneath where the padlock was hanging
Correct answer: The cut face of the shackle, noting the angle, tool width impression, and any transferred metal
The cut face of the shackle shows the tool's bite geometry, cutting angle, and potentially transferred metal that can be matched to a specific suspect tool.
Question 5: When should a CFL request a latent fingerprint examination before proceeding with lock examination?
- Always, before any handling of lock surfaces, since fingerprint processing must precede other forensic steps (Correct answer)
- Only if the property owner specifically requests fingerprint analysis
- Only after the lock has been fully disassembled in the laboratory
- Only if a specific suspect is already in custody and prints are available for comparison
Correct answer: Always, before any handling of lock surfaces, since fingerprint processing must precede other forensic steps
Fingerprint processing must always precede other forensic examinations because any handling of the lock surface destroys latent print evidence that cannot be recovered afterward.
Question 6: What is a 'scene sketch' and why does a CFL produce one at an investigation site?
- A scaled or proportional drawing recording the lock's position relative to the overall scene layout (Correct answer)
- A freehand artistic rendering of what the CFL believes happened during the incident
- A diagram showing the CFL's recommended replacement hardware layout for the property
- A drawing of the suspect's tool kit reconstructed from the tool marks observed
Correct answer: A scaled or proportional drawing recording the lock's position relative to the overall scene layout
A scene sketch provides a spatial record of the lock's location and context within the overall scene, complementing photographs that may lack accurate spatial relationships.
CFL Crime Scene Investigation Procedures 2
What is 'chain of custody' and why is it critical for a CFL's forensic work?