Factors affecting the accuracy of eyewitness testimony (EWT)

• Identify the three factors affecting the accuracy of the eyewitness testimony

  Leading questions and post-event discussions (both types of misleading information) Anxiety
• Outline research into leading questions as a factor affecting EWT

  Research has found that leading questions affect the accuracy of EWT because they are phrased in a way to suggest a certain answer, and this answer may not

  be correct. one piece of research involved presenting university students with video clips of cars colliding before being asked to estimate the speed at which they were travelling.
• Outline research into leading questions as a factor affecting EWT - participants were asked key question

  before being asked to estimate the speed, the participants were asked the key question: How fast were cars going when they ___ each other? Each group was given a verb. - smashed, collided, bumped, hit or contacted. The research found verb 'smashed' resulted In the fastest estimate of speed while the verb 'contacted' resulted in the slowest estimate of speed. suggests that the verb used created a leading question
• Limitation of research into the effects of leading questions is that it has been criticised for exaggerating its effects

  This is because university students, who typically have limited driving experience, took part in the car crash study. limitation because it could be argued that the verb did not actually alter their memories. Instead, because they had limited driving experience, they just relied on it to provide an estimate of speed. This means that other groups (e.g. older adults with more driving experience) would have been less affected by the leading questions asked. ? credibility.
• A strength of research into leading questions is that it has received supporting evidence.

  For example, in a later replication of the car crash study, participants were also asked whether they had seen any broken glass in the video clips of the cars colliding. They found that participants who were originally given the verb ‘smashed' were most likely to report seeing broken glass, even though there wasn't any. This is a strength as it shows that the verb used in the leading question did actually alter participants' memory of the incident. Therefore adds credibility.
• Limitation of research - most of it has been conducted in artificial environment

   

  the car crash study was conducted in a controlled laboratory setting. limitation because participants would have known they were just taking part in research and were not witnessing a real crime where there could be legal consequences when giving their testimony - someone to prison - they may be less likely to carefully consider their testimonies and so are more likely to be influenced by leading questions. This means that leading questions may not have such a significant effect irl. questions credibility
• Limitation leading q - artificial tasks

  the car crash study involved participants watching staged video clips of two cars crashing. This is a limitation because such tasks will not cause participants to feel the emotional distress that they would typically feel if they were a witness to a real-life, live crime. As a result, because of the lack of emotion in this research, participants may be more misled by the leading questions. Again this means that loading questions may not have such a significant effect in real life eyewitness cases. questions credibility.
• Outline research into post-event discussion as a factor affecting EWT

  Research has found that post-event discussion can lead to innacurate eyewitness testimonies due to two reasons: memory contamination and memory

  conformity.
• Outline research into post-event discussion as a factor affecting EWT - memory contamination and social approval

  Memory contamination refers to when eyewitnesses discuss what happened and, because their memory may be affected by their own biases and schemas, they may alter others’ memories into thinking they had witnessed things they actually didn't. Memory conformity refers to when witnesses discuss what happened and this leads some to go along with the others (even if they think they are wrong) for social approval.
• Outline research into post-event discussion ad a factor affecting EWT - example

  one piece of research involved participants watching a video of a girl whereby some participants witnessed the girl stealing money from a wallet while others did not. They were then either allowed to engage in post-event discussion or were kept alone before being tested on their recall. They found that the majority of those who were allowed to engage in post-event discussion recalled the girl stealing the wallet, even though half of them did not actually witness this. decrease accuracy of EWT.
• Limitation of research into the effect of PED - artifical environment

    the study of the girl stealing/not stealing the wallet was conducted in a controlled laboratory setting. limitation because participants would have known they were just taking part in research and were not witnessing a real crime where there could be legal consequences of their testimony - sending someone to prison - they were less likely to consider their testimonies and so would be more influenced by post-event discussion. post-event discussion may not have such a significant effect in irl cases. ? credibility.
• Post-event discussions - artificial tasks

  the above research involved participants watching a staged video clip of a girl stealing/not stealing a wallet. limitation because such tasks will not cause participants to feel the emotional distress that they would typically feel if they were a witness to a real-life, live crime. because of the lack of emotion in this research, participants may be more misled by the post-event discussion. this means that post-event discussion may not have such a significant effect in real life cases. questions credibility.
• Post-event discussion resulted in practical application

  the finding that post-event discussion can negatively impact recall has resulted in police offers minimising opportunities for witnesses to discuss what they had

  seen with one another. This Is a strength because such changes in police practice have helped to improve the accuracy of eyewitness testimonies, thus maximising the chances of a successful conviction. Therefore adds credibility.
• Outline research into anxiety as a factor affecting EWT

  participants experience high levels of anxiety, their eyewitness testimonies are less accurate. in one study, participants heard a discussion in a room before a man came out carrying either: a pen with grease on his hands, or a knife with blood on his hands. participants were able to correctly identify the man from a photo line-up when he was seen holding a pen than an anxiety-inducing knife. - bc - the weapon-focus effect - the knife creates feelings of anxiety so witnesses overly focus on the weapon rather than other details
• Outline research into anxiety as a factor affecting EWT - HIGH LEVEL OF ANXIETY

   real-life eyewitness cases have found that when witnesses experience high levels of anxiety, their eyewitness testimonies are more accurate.

  For example, witnesses to a real-life armed robbery were interviewed months after the crime whereby they were asked to rate how anxious they felt and what

  they had witnessed. They found that that those who reported being the most anxious produced the most accurate testimonies.
• Contradictory findings

  Such contradictory findings can be explained by the Yerkes-Dodson law which proposes that low or extreme levels of anxiety (e.g. as seen in the laboratory

  research with the knife and blood) impairs recall while moderate amounts of anxiety (e.g. as seen in the real-life case of the armed robbery) improves recall.
• effects of anxiety is that weapon focus effect may be due to surprise rather than anxiety

  witnesses may have paid too much attention to the weapon due to its unusualness rather than due to it causing anxiety. participants asked to watch a video of a thief entering a hairdressing salon carrying one of the following objects: scissors, a gun, a wallet or raw chicken. found that participants' testimonies were poorest when the thief was holding the gun + raw chicken. limitation - that it may be surprise (both a raw chicken and a gun) rather than how anxiety that affects recall. ? credibility.
• Limitation of the real life robbery research on anxiety - affected by confounding variables

   This is because those who reported the highest level of anxiety were closer to the robbery and so this may have improved their testimony in comparison to those who were less anxious/further away. This is a limitation because it means it is difficult to establish whether the differences in the accuracy of their recall was due to their position during the incident or the level of anxiety they felt. Therefore questions credibility.
• Effects of eyewitness testimony is that it may be affected by individual differences

  research has found that those who score low on neuroticism (who do not tend to get anxious as easily) produce better eyewitness testimonies when anxiety levels rise. those who score high on neuroticism (tend to get anxious easily) produce poorer eyewitness testimonies when anxiety levels rise. This is a limitation because it suggests that it is difficult to generalise the effects of anxiety on the accuracy of EWT as it depends on personality traits Therefore questions credibility.
• Research into the effects of anxiety on the accuracy of EWT - ethical implications

  the research finding that witnesses who experience a high level of anxiety produce less accurate testimonies may result in the public, jury members and judges disregarding testimonies from witnesses/victims to serious crimes. This is a limitation because it may lead to further distress to victims who feel that their voices are not being heard and may result in the offender escaping criminal justice due to a lack of evidence. Therefore questions credibility.
• Outline the cognitive interview as a way of improving the accuracy of EWT

  cognitive interview is a technique used by police officers to obtain more accurate information from eyewitnesses in comparison to the standard police

  interview. It comprises of 4 main techniques: report everything, context reinstatement, recall from a changed perspective and recall in reverse order.
• Outline report and context reinstatement

  The report everything technique involves the officer encouraging witnesses to report all details of the event regardless of how unimportant they may seem.

  This improves accuracy by encouraging witnesses to report details they may have initially overlooked.

  Context reinstatement involves the officer asking the witness to try and mentally place themselves back at the scene of the crime and recall environmental

  information. This improves accuracy by reinstating context-dependent cues which could trigger other memories.
• Outline recall from a changed perspective and in reverse order

  Recall from a changed perspective involves the officer asking the witness to try and describe what another witness may have seen. This improves accuracy by

  promoting a more holistic view of the event.

  Finally, recall in reverse order involves the officer asking the witness to recall the event backwards i.e. from the end to the beginning. This improves accuracy as

  it can verify whether the witness is telling the truth (as it is harder to lie when telling a story backwards).
• Cognitive interview - contradictory evidence

  one piece

  research found that while the cognitive interview did lead to an 81% increase in correct information, it also led to a 61% increase in incorrect information.

  This is a limitation because it would be difficult for the police to assess which parts of an eyewitness' testimony is correct or incorrect and, if they use the

  incorrect information, it could mislead the police investigation. Therefore questions credibility.
• Strength of cognitive interview is that it has been found to be beneficial in older witnesses.

  negative stereotypes about older people's memories (i.e. that it gets worse with age) makes elderly people reluctant to provide details in case they are wrong. This is a strength because the cognitive interview emphasises the importance of reporting everything and so has helped encourage older witnesses to report more details to improve their testimonies. Therefore adds credibility.
• Cognitive interview is that it does not improve the accuracy of EWT in children

   This is because research has found that in children

  under 6, their recall of events was less accurate when using the cognitive interview than when using the standard interview. This is a limitation because it

  suggests that some of the techniques used (such as recalling in reverse order) may be too challenging for younger witnesses. Therefore questions credibility.
• Cognitive interviews limitation on improving accuracy is that it is not always practical to carry out

  This is because it requires training police officers which can be time consuming and costly. This Is a limitation because limited police resources mean officers may not be adequately trained and so may not carry out the cognitive Interviews correctly. If this was the case, they would have no benefit in improving the accuracy of eyewitness testimonies. Therefore questions credibility