Observation and Memory Skills Flashcards

During a witness interview, a subject describes a suspect's jacket as 'bright red' immediately after the incident but later recalls it as 'dark maroon' three days later. Which memory phenomenon BEST explains this change?

Answer: Post-event information effect, where subsequent exposure to related cues reconstructed the original memory trace

The post-event information effect (also called misinformation effect, identified by Loftus) occurs when information encountered after an event — news coverage, conversations, or leading questions — is integrated into the original memory, subtly altering the recalled details. This is distinct from simple decay (which degrades detail quantity, not substitutes new colours) and from confabulation (a clinical condition). Weapon focus applies when a weapon was present; there is no weapon mentioned here.

An officer uses the cognitive interview technique and asks a witness to mentally reinstate the environmental and personal context of the event before describing what happened. What is the PRIMARY theoretical basis for this instruction?

Answer: State-dependent memory and encoding specificity, whereby retrieval cues that match encoding conditions enhance recall accuracy

The 'mental reinstatement of context' component of the cognitive interview is grounded in encoding specificity and state-dependent memory: recall is most accurate when retrieval conditions (internal state, environmental cues) approximate those present during encoding. Elaborative rehearsal improves retention through repetition but is not the mechanism invoked by mental reinstatement. Chunking and the serial position effect address different memory structures and are not the basis for this specific technique.

An officer observing a crowded intersection notices a vehicle, later relevant to an investigation, but cannot recall its licence plate or make. Forensic memory research would MOST accurately attribute this to:

Answer: Inattentional blindness caused by the officer's attentional resources being focused on task-irrelevant stimuli at the time of observation

Inattentional blindness occurs when an observer fails to perceive a stimulus that is fully within their visual field because attentional resources are allocated elsewhere. In a crowded intersection, attention directed at pedestrians, traffic signals, or other focal events can cause an unattended object — like a specific vehicle — to go unencoded entirely. Retrograde amnesia requires a neurological disruption event. Source monitoring error implies the item was encoded but misattributed. Proactive interference disrupts new encoding via competition from similar prior memories, which is a different mechanism.

During a lineup procedure, a witness identifies a suspect but expresses only 60% confidence. Research on eyewitness memory MOST strongly indicates that:

Answer: Low confidence expressed at the time of the initial identification is a more reliable predictor of inaccuracy than high confidence expressed after post-identification feedback

Research (including the National Academy of Sciences 2014 report on eyewitness identification) consistently shows that initial confidence — expressed before any confirming feedback — is the most valid measure of identification accuracy. Post-identification feedback ('you picked the right guy') inflates confidence without improving accuracy. Moderate confidence is not equivalent to a non-identification; it carries diagnostic weight. Confidence does not reliably consolidate upward over time — the pattern is typically the reverse due to memory decay. The 80% threshold described in option D has no empirical basis in standard lineup protocols.

An officer preparing testimony must recall the sequence of events from a scene documented two months prior. Which encoding strategy, if applied at the time of the original observation, would MOST reliably support accurate sequential recall months later?

Answer: Deep semantic encoding — actively associating each observed element with its functional meaning or investigative significance at the time of observation

Depth of processing theory (Craik & Lockhart) demonstrates that memories encoded at a deep, semantic level — where meaning, relevance, and context are actively processed — yield more durable and retrievable long-term traces than those encoded structurally (visual form only) or through shallow rote rehearsal. For an officer, connecting each observation to its investigative significance at encoding (e.g., 'this broken lock indicates point of entry') constitutes deep semantic processing. Rote rehearsal produces surface-level traces prone to rapid decay. Structural encoding is shallower than semantic encoding. Binary 'important/unimportant' tagging oversimplifies and loses contextual nuance needed for sequential recall.

A detective reviews CCTV footage and notices a person who appears in the background of three separate camera angles over 11 minutes. The person's face is never fully visible, but the detective is confident of a match to a known subject based on gait and clothing. Which evidentiary caution MOST applies when the detective presents this observation in court?

Answer: Own-race bias does not apply, but holistic face processing cannot be substituted for gait analysis — each requires distinct expert validation, and the officer must clearly delineate the perceptual basis for the identification to avoid conflating two separate recognition mechanisms

Courts and memory science both distinguish between face recognition (a holistic perceptual process subject to own-race bias and other distortions) and gait/feature recognition (a different perceptual mechanism requiring its own reliability foundation). When an officer offers an identification based on gait, clothing, and indirect features rather than face, they must clearly articulate which cues were used and avoid suggesting that the identification carries the same weight as direct facial recognition. Option B misrepresents the Morin admissibility framework. Option C overstates the automatic admissibility of lay opinion — qualification depends on the nature of the opinion and judicial discretion. Option D ('cumulative observation doctrine') is not a recognized legal principle that transforms partial sightings into a complete identification.