EWT Flashcards
(20 cards)
How does post-event discussion lead to misleading information
Misleading information can impact memory when witnesses talk to other people about what they have seen
What is the research into how post-event discussion reduces reliability of EWT
Gabbert et al.
60 students and 60 older people watched a video of a girl stealing money from a wallet. Recall was tested individually or in pairs(co witness group) Those in the co-witness group were unaware when they had watched different videos but were allowed to discuss what they had witnessed
71% of the witnesses in the co-witness group recalled information they had not seen and 60% said that the girl was guilty, even though they had not seen her commit a crime
Strengths of research into post event-discussion
Positive implication: research informs the police about how to interview witnesses. For example, interview them alone without the influence of others
Weaknesses of research into post event discussion
Participants knew they were taking part in a study and the ‘incident’ was on a video meaning the study lacks ecological validity
It is not clear why post-event discussion misleads memory. It could be contamination of EWT or it could be conformity to co-witnesses.
How do leading questions reduce validity of EWT
Questions can suggest information to witnesses, causing a change in what they recall. E.g. did you see the broken glass?
What was the research into Leading Questions
Loftus and Palmer
They asked 45 American students to watch a video of a car incident and to estimate the speed of cars. Each group was asked a critical question: ‘How fast were the cars going when they …? with the verb being changed each time
Smashed= 41%
Collided= 39%
Bumped=38%
Hit=34%
Contacted= 32%
Strengths of research into Leading questions
In a second study participants were asked if they saw any broken glass. Those who were asked about speed with the verb ‘smashed’ were more likely to say yes, despite there being no broken glass- practical application into reliability of EWT
Weaknesses of research into Leading Questions
The artificial video and lack of real emotions and consequences means that the study by Loftus lacks mundane realism and thus ecological validity
The study lacks generalisability as it only uses students from America and cannot be applied beyond this sample
What is the Yerkes-Dodson effect
suggests that when anxiety is moderate, then EWT is enhanced; however, when anxiety is very high then accuracy is reduced
What research was conducted into anxiety in EWT
Johnson and Scott 1976
Participants came to a lab and were told t wait in the recepton area. A receptionist excused herself to run an errand, leaving the participant alone.
In the no weapon condition: participants overheard a conversation in the lab about equipment failure and saw an individual walk past holding a pen, with his hands covered in grease
In the weapon condition: participants overhead a heated exchange, the sound of breaking glass and crashing chairs. They saw an individual running into reception holding a bloodied letter opener
When asked to look at photographs and identify the person who left the lab, those in the weapon conditio did so correctly 33% of the time, compared to 49% for the no weapon condition
Therefore high anxiety was detrimental to EWT
What is the contradictory research to high anxiety reducing EWT
Yuille and Cutshall investigated the effect of anxiety in real-life shooting, in which one person was killed and another person seriously injured. 21 witnesses were interviewed by the police at the time
13 witnesses agreed to take part in the follow-up research interview 4-5 months later
The 13 witnesses were accurate in their eyewitness accounts 5 months later and little changes was found in their testimonies
These results refute the weapon focus effect and results of Loftus(1979) and show that in real-life cases of extreme anxiety, the accuracy of eyewitness testimony is not affected
Evaluation of research supporting anxiety reducing validity of EWT
The study by Johnson and Scott lacks ecological validity since it was an orchestrated situation. Participants may have guessed something was going on, which would lead to demand characteristics
The study can also be criticised for being unethical due to the deception and withholding of information about the true aims of the study, and the distress participants may have experienced,
Most research into anxiety and EWT takes a nomothetic approach, which helps to generate laws of behaviour, but is problematic since the sample of participants is small and not representative of the wider population
How can we improve the accuracy of EWT
Cognitive interviews
What are the 4 components of cognitive interviews
Context reinstatement, report everything, recall from a different perspective, recall in reverse order
What is context reinstatement
Witnesses are asked to recall the context of what they experienced, such as the weather, time of day and how they felt. This will help to trigger memories of what they saw
What is report everything
Witnesses are asked to report everything they can remember or that comes to mind, no matter how trivial it may seem
What is recall from a different perspective
Witnesses are asked to consider the situation from someone else’s point of view. For example, what the attacker may have seen
What is recall in reverse order
Witnesses are asked to recall the events in different chronological order
What is the research conducted into cognitive interviews
Geiselman asked participants to watch a video of a stimulated crime, then interviewed them the following day with a cognitive interview, or a standard interview. The cognitive interview led to more accurate information being recalled. However, it also led to more inaccurate information being recalled then the standard interview
Centofanti and Reece showed participants a video of a bank robbery and gave thema misleading or neutral event summary. Although everyone was susceptible to misleading information, participants who were questioned with a cognitive interview recalled 35% more than those who were not
Evaluation of cognitive interviews
Specialist and extensive training is required for the cognitive interview technique to be used properly and for it to be effective in improving the accuracy of EWT. However, most police forces do not receive adequate training
Establishing the effectiveness of the cognitive interview is hard since not all polcie forces use it in the same way. For example, some forces will use all four components, some will only use two
The research shows that despite there being evidence to suggest that cognitive interviews is effective at improving accuracy in EWT, it will also produce inaccurate information, and vast amounts of information, which is not always helpful to investigations
