Evidence Collection & Forensic Analysis Flashcards
7 cards from real CMI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Evidence Collection & Forensic Analysis flashcards as text
When photographing a vessel casualty scene, what is the correct sequence for documenting physical evidence?
Answer: Wide-angle overview shots first, then progressively closer detail shots
Proper forensic photography follows a wide-to-close sequence: overview, mid-range, and close-up shots to establish context before recording detail.
A marine investigator discovers an oily residue on the bilge pump discharge. Which chain of custody action is most critical at this point?
Answer: Collect the sample immediately, seal and label it with date, time, location, and collector identity
Chain of custody requires immediate collection, proper sealing, and complete labeling at the moment of discovery to prevent contamination or tampering.
What type of fracture pattern in a vessel's hull plating is most indicative of an internal explosion rather than a collision?
Answer: Outward-directed petaling with deformation radiating away from the blast center
Internal explosions push hull material outward, creating outward-petaling fractures with deformation radiating away from the blast's origin point.
During a fire investigation aboard a vessel, investigators find the deepest char at the lowest point of a V-pattern burn. What does this most likely indicate?
Answer: The fire originated near the base of the V-pattern, consistent with a low burn origin
A V-pattern with the deepest char at its base indicates a low point of origin, as fire burns upward and outward from its ignition source.
When collecting water samples as evidence in a pollution investigation, how should samples be stored to preserve their evidentiary value?
Answer: In amber glass containers, refrigerated at 4°C, with appropriate preservatives per analyte
Amber glass prevents photodegradation, refrigeration at 4°C slows microbial activity, and preservatives are required depending on the specific analytes being tested.
A marine investigator is documenting a grounding incident. What information is essential when sketching the scene at the point of first contact?
Answer: Position coordinates, water depth, bottom composition, tide stage, and direction of vessel travel
An accurate grounding scene sketch requires position, depth, bottom type, tide stage, and vessel heading to reconstruct how and why the vessel struck bottom.
Which document is the primary forensic record of a vessel's movements and crew actions leading up to a marine casualty?
Answer: Official deck logbook maintained by the officer of the watch
The official deck logbook is the contemporaneous, legally required record of navigational events, weather, and crew actions maintained throughout the voyage.