Key Questions (Edexcel A-Level Psychology): Revision Notes
Reliability of Eyewitness Testimony
What is eyewitness testimony?
Eyewitness testimony refers to information provided by a witness who has observed an event or crime. This evidence is documented in police statements or presented as verbal testimony during court trials. Eyewitness accounts often serve to support forensic evidence, though jurors may struggle to understand complex forensic evidence in trials and therefore place greater reliance on witness testimony they can relate to and feel confident about.
When forensic evidence is absent, eyewitness testimony becomes particularly influential and may be essential in determining trial outcomes. This creates a critical situation where inaccurate testimony could result in wrongful convictions or allow guilty individuals to escape justice.
Jurors must assess whether to convict someone based on the evidence presented, meaning the accuracy and reliability of eyewitness testimony has significant real-world consequences for defendants within the criminal justice system.
The reliability concern
Research examining the accuracy of eyewitnesses suggests they may be less reliable than commonly believed. This concern formed the basis of a judicial review resulting in the Devlin Report (1976).
The Devlin Report concluded that courts should exercise considerable caution when relying solely on eyewitness testimony without additional corroborating evidence. This recommendation highlights serious concerns about the potential for unreliable testimony to lead to miscarriages of justice.
Reconstructive memory and eyewitness reliability
Research into reconstructive memory raises questions about how reliable eyewitnesses can be. Bartlett's (1932) theory of reconstructive memory explains that people attempt to match what they remember with their existing knowledge and understanding of the world. This process can cause eyewitnesses to reconstruct memories of events to align with their understanding or expectations within a situation.
How schemas influence eyewitness recall:
A perpetrator's appearance or accent may activate the eyewitnesses' schemas about the type of person who commits crimes, influencing how they encode and later recall the perpetrator. The witness may remember the perpetrator differently from reality because their schemas have shaped their memory.
For instance, if a witness has schemas associating certain physical characteristics with criminal behavior, they may unconsciously alter their memory to match these preconceived expectations rather than what they actually observed.
Post-event information effects
Post-event information encompasses anything an eyewitness encounters after the event but before providing testimony at trial. This can produce inaccurate memories, as new events or information may modify the memory of the original event.
Elizabeth Loftus conducted numerous studies on leading questions, demonstrating how the way witnesses are questioned can alter their memories. This makes it difficult to separate their genuine memory of the event from the additional influences present when providing testimony at trial.
The danger of leading questions:
Loftus's research showed that even subtle changes in question wording can significantly alter witness recall. This means that the manner of questioning itself becomes a factor in memory accuracy, not just the witness's original observation. This has profound implications for police interview techniques and courtroom questioning procedures.
Factors affecting eyewitness reliability
Multiple factors influence the accuracy of eyewitness recall. Understanding these factors is essential for evaluating the reliability of testimony in any given case.
Individual characteristics of the witness:
- Age of the witness
- Other personal factors affecting perception and memory
Contextual factors associated with the event:
- Lighting conditions at the time of observation
- Presence of a weapon (which may draw attention away from other details)
Post-event factors:
- The manner in which a witness is questioned
- The duration of time between the event and being asked to recall what occurred
These three categories of factors - Individual, Contextual, and Post-event - can interact in complex ways. A witness may be more affected by poor lighting if they are elderly, or the impact of time delay may be reduced if questioning methods are optimal. Understanding these interactions is crucial for assessing testimony reliability.
The laboratory versus naturalistic research debate
Despite concerns about eyewitness testimony accuracy, research questions the validity of applying laboratory findings to real-world situations. This debate centers on whether laboratory research accurately reflects real-life eyewitness conditions.
Yuille and Cutshall (1986)
Researchers: Yuille and Cutshall
Year: 1986
Type: Naturalistic case study
Aim: To compare eyewitness accuracy in real-life conditions versus laboratory experiments.
Method: The researchers examined witness statements from survivors who had witnessed a real crime. They analysed the accuracy of recall rather than conducting an artificial laboratory experiment.
Findings: When using a naturalistic case study approach, real-life eyewitnesses demonstrated considerable accuracy in their recall. Importantly, they were not influenced by leading questions, even after an extended period between the initial event and recall.
Evaluation - Strengths:
- High ecological validity as it examined real-life eyewitness testimony
- Demonstrates that laboratory findings may not generalise to actual criminal situations
- Shows eyewitnesses can be accurate in realistic conditions
Evaluation - Weaknesses:
- Difficult to control extraneous variables in naturalistic settings
- Cannot establish cause-and-effect relationships as clearly as laboratory experiments
- Limited ability to replicate the exact conditions
Thompson (1997)
Researcher: Thompson
Year: 1997
Type: Study of real trauma survivors
Participants: Survivors of the sunken riverboat, Marchioness
Aim: To examine the accuracy of recall following extreme emotional trauma.
Findings: Despite experiencing severe emotional trauma, witnesses recalled events with considerable accuracy after many months had passed.
Why laboratory research may not reflect real-world conditions:
This research suggests that laboratory conditions may not replicate the circumstances experienced by actual witnesses. Key differences include:
- Emotional involvement: Experimental research participants are onlookers, so the emotional involvement of witnessing a genuine event is not reproduced
- Awareness of observation: Participants in laboratory studies are aware they are being observed and must pay attention to what they have been asked to witness
- Nature of events: Real-life events are typically unexpected, confusing and occur rapidly, unlike controlled laboratory scenarios
- Perceived importance: Real-life witnesses understand their testimony holds genuine importance as it may affect police investigations or trial outcomes
This heightened importance and emotional involvement may actually enhance attention and recall in ways that cannot be reproduced in laboratory settings.
Steyvers and Hemmer (2012)
Researchers: Steyvers and Hemmer
Year: 2012
Type: Laboratory study
Aim: To investigate whether prior knowledge from semantic memory contributes to accurate recall in episodic memory tasks when recalling naturalistic scenes.
Findings: The study demonstrated that prior knowledge drawn from semantic memory could enhance accurate recall in episodic memory tasks.
Challenge to experimental research validity:
This research seriously challenges the validity of experimental research claiming that eyewitness testimony is unreliable. The findings suggest that numerous experimental studies actively construct situations that promote flawed recall, such as placing an unusual object within a scene.
This methodology does not accurately reflect real-life circumstances, where the contexts of crimes being committed are generally fairly normal. If semantic memory helps accuracy in naturalistic contexts, then laboratory studies using unusual scenarios may systematically underestimate real-world eyewitness accuracy.
Yarmey (2004)
Researcher: Yarmey
Year: 2004
Type: Field experiment
Aim: To examine identification accuracy of a person encountered in a street using a more realistic methodology.
Method: Participants were later shown photographs and asked to identify the person they had seen.
Findings: Correct identification occurred in approximately 50% of cases.
Implications: Whilst these findings do not support arguments for eyewitness testimony reliability using more realistic methodology, they highlight the need for further research conducted outside laboratory settings so findings can be considered more ecologically valid.
Flashbulb memories
Flashbulb memories are particularly vivid and detailed memories that can occur when an event witnessed has strong emotional impact on the individual.
Hirst et al. (2009) demonstrated that memory recall for emotional events remains accurate over extended periods, though it gradually fades like most memories. However, the evidence for flashbulb memory has been mixed, with other studies suggesting it is not a genuine phenomenon and does not enhance recall accuracy.
Neisser and Harsch (1992) found that flashbulb memories, whilst initially vivid, do not necessarily increase the accuracy of recall over time. This suggests that the vividness of a memory does not guarantee its accuracy.
Evaluation of eyewitness testimony reliability
Arguments supporting unreliability:
- Laboratory research demonstrates multiple factors that reduce accuracy (leading questions, post-event information, reconstructive memory processes)
- The Devlin Report (1976) recommended courts exercise caution when relying on eyewitness testimony alone
- Schemas and expectations can distort memory reconstruction
- Yarmey (2004) found only 50% identification accuracy in field conditions
Arguments supporting reliability:
- Naturalistic research shows greater accuracy than laboratory studies suggest
- Yuille and Cutshall (1986) found real-life witnesses were accurate and resistant to leading questions
- Thompson (1997) demonstrated accurate recall even after extreme emotional trauma and extended time periods
- Flashbulb memories may preserve accuracy for emotionally significant events
- Real-life witnesses have motivation and emotional involvement that enhances attention and recall
Overall conclusion:
Evidence from naturalistic research suggests eyewitness testimony can be accurate, particularly for real-life events. However, substantial experimental evidence indicates we should remain cautious about relying on eyewitness testimony.
Further research is needed to establish which factors most significantly influence eyewitness testimony reliability, and how these factors interact to either improve or diminish recall accuracy. The debate between laboratory and naturalistic research highlights the importance of ecological validity when studying eyewitness testimony.
Exam approach for key issue questions
Structuring your response:
When addressing key issues in examinations, structure your response as follows:
Key question: Is eyewitness testimony reliable?
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Outline the key question: Define eyewitness testimony and explain why this issue matters for defendants within the criminal justice system
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Arguments for eyewitness testimony being unreliable: Present evidence and psychological concepts supporting concerns about reliability
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Arguments for eyewitness testimony being more accurate than thought: Present evidence and psychological concepts suggesting eyewitness testimony can be reliable
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Conclusion: Provide a balanced judgement based on the evidence presented, recording a clear conclusion about the issue
Remember!
Key Points to Remember:
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Eyewitness testimony is witness information given about observed events or crimes, used in police statements and court trials - it can be influential but potentially unreliable
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Reconstructive memory theory (Bartlett, 1932) explains how schemas and expectations can distort recall, causing eyewitnesses to remember events differently from how they actually occurred
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Post-event information, particularly leading questions (Loftus), can alter eyewitness memories, making it difficult to separate genuine memories from influences encountered after the event
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Laboratory versus naturalistic research shows conflicting findings: laboratory studies suggest unreliability whilst naturalistic studies (Yuille and Cutshall, 1986; Thompson, 1997) demonstrate greater accuracy in real-world conditions
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Multiple factors affect reliability including individual characteristics (age), contextual factors (lighting, weapon presence), and post-event factors (questioning method, time delay between event and recall)