The Witness Who Became Certain
Meera, 16, is travelling home at 7:30 p.m. when a man on a motorcycle snatches a woman's gold chain at a bus stop. Meera is standing about 10 metres away under a streetlight, and the incident lasts roughly 20 seconds. The rider wears a full-face helmet and a blue shirt. Meera gives a statement to the police that night. Two days later she views a photo lineup of six similar men and identifies No. 3 with low confidence. That evening she watches a local news clip of a suspect in a blue shirt and talks to a friend who says, 'It must be the man in blue.' Four months later, in court, Meera identifies the same man with high confidence and adds details about a tattoo she did not mention earlier. The defence lawyer says she is lying; the prosecutor says her certainty proves accuracy. The judge must decide how much weight to give her identification.
1. Explain how encoding, storage and retrieval could each contribute to error in Meera's identification. Apply each stage to the details rather than simply listing the stages.
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Encoding Encoding is what Meera takes in at the time. She was 10 metres away, the incident lasted about 20 seconds, and the rider wore a full-face helmet. These conditions limit detail. High stress can narrow attention, so she may have focused on the motorcycle or the chain rather than the face. The streetlight helped, but it does not guarantee a clear view of a partly covered face.
Storage Storage is what is retained over time. Meera gave a statement that night, then saw a photo lineup two days later, a news clip, and a friend's comment. Over four months, these experiences can blend with the original memory. This is post-event information: later suggestions can be absorbed into the memory and later recalled as if they were original. Repeated retelling can also change details.
Retrieval Retrieval is what Meera produces when asked. Photo lineups, court questioning and stress can affect retrieval. The lineup may have contained no correct person, yet she chose the closest match. Her low confidence at the lineup and high confidence in court show that retrieval conditions and feedback changed her expression of memory. The new 'tattoo' detail may be a reconstruction rather than a recovered fact. Errors can therefore arise at any stage, not only from dishonesty.
2. How would you explain the rise in Meera's confidence between the lineup and the trial? Use memory principles.
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Confidence is not a direct readout of memory accuracy. Meera's confidence can rise without a genuine increase in reliable information for several reasons:
- Post-event suggestion: the news clip and her friend's comment provide a plausible suspect. Repeated exposure makes that face feel more familiar.
- Reconstructive memory: remembering is not replaying a video. Meera may fill gaps using later information, then experience the reconstructed version as a real memory.
- Source monitoring error: she may remember the face but forget where the information came from-the crime, the lineup, or the news.
- Rehearsal and feedback: choosing No. 3 and later receiving confirmation can increase certainty. Rehearsing the identification makes it fluent, and fluency is easily mistaken for accuracy.
- Repeated questioning: each retelling can add detail and confidence, especially if questioners reward certainty.
The prosecutor's claim that certainty proves accuracy is therefore weak. The court should give more weight to the conditions of the first identification, the initial confidence statement, and the fact that the lineup was conducted soon after the crime. The defence's claim that she is lying is also too strong: an honest witness can be confidently wrong.
3. The judge asks whether Meera is lying. Give a reasoned answer and suggest two procedural reforms to the photo lineup.
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Is Meera lying? Lying requires deliberate intent to deceive. The details are more consistent with honest memory error than with lying: she identified with low confidence at first, then received post-event information, and later became certain. Her new detail may be a reconstruction. Without evidence of intentional fabrication, the judge should not treat confidence or inconsistency alone as proof of lying. At the same time, her identification should be treated cautiously because the original encoding conditions were limited and later contamination was possible.
Two lineup reforms
- Double-blind administration: the officer conducting the lineup should not know which photo is the suspect. This prevents accidental cues, such as a pause or tone change, that push the witness toward a face.
- Unbiased instructions and a proper filler set: tell the witness clearly that the offender may or may not be present and that the investigation will continue either way. Use fillers who match the description, not just the suspect. A sequential presentation, where photos are shown one at a time, can also reduce relative judgments.
Other useful reforms are recording the witness's confidence immediately after the choice and avoiding repeated feedback. These changes protect both the innocent suspect and the genuine witness.