Memory: Eyewitness Testimony (L10-12) Flashcards
(27 cards)
What is an eyewitness testimony?
- the evidence supplied to a court by people who have seen a crime, based on their memory of the incident
- this evidence can include identification of the perpetrator or details of the crime
- juries are often heavily influenced by eyewitnesses
What are leading questions?
- questions that are phrased in such a way to encourage a witness to give a certain answer
What is the response-bias explanation, LQ?
- argues that leading questions do not affect memory
- affects merely the answer a person chooses to give
What is the substitution-bias, LQ?
- proposes that leading questions distort memories because they contain misleading information
LQ, Procedure of Loftus and Palmer (1974)?
- showed 45 American students a film of a car crash
- asked them to estimate the speed that the cars were travelling when they crashed
- however, different verbs were used in the questions depending on the condition
- the verbs were contacted, hit, bumped, collided, or smashed
LQ, Findings of Loftus and Palmer (1974)?
- participants in the ‘contacted’ condition estimated the speed as 31mph
- ‘smashed’ estimated 41mph
- a week later participants were asked if they saw any broken glass
- even though there was no broken glass shown in the film, 32% of Ps in the ‘smashed’ condition reported seeing brown glass
- compared to only 12% in the control condition (contacted)
- shows that leading questions have a significant impact on what people recall and can change a persons entire memory of an event
Evaluation of Loftus and Palmer (1974) +ve:
- laboratory experiment therefore highly controlled
- reduces the chance of extraneous variables, increasing the validity of the results
- therefore, easy for psychologists to replicate their research study to see if the same results are found
- meaning study is reliable
Evaluation of Loftus and Palmer (1974) -ve:
- questionable ecological validity as Ps watched a video of a car crash
- people who witness a real car accident will have a stronger emotional connection the the event
- may not be as susceptible to leading questions
- lacks population validity, study consists of 45 American students
- students less experienced drivers so may be less competent at estimating speeds
- also unable to generalise the results of this study to other populations
- older and more experienced drivers may be more accurate in their judgment of speeds and therefore less susceptible to leading questions
How can memory be distorted?
- leading questions
- post event discussion
What is memory contamination, PED?
- the memory of an event can be contaminated through discussing events with others due to misinformation
What is memory conformity, PED?
- a desire for social approval can lead co-witnesses to reach a consensus view of what happened
PED, Procedure of Gabbert et al. (2003)?
- put Ps in pairs and got them to watch a different video of the same event so that they each got unique details
- in one condition the pairs were encouraged to discuss the event with one another before individually recalling the event
- in the other condition they did not discuss what they had seen with one another
PED, Findings of Gabbert et al. (2003)?
- 71% of witnesses who had discussed the event went on to mistakenly recall details that they could not have seen themselves
- but that they had learned of during the discussion with their partner
Evaluation of Gabbert et al. (2003) +ve:
- study has population validity
- 2 different populations, students and older adults, were compared and there were no significant differences between these 2 groups
- allows us to conclude that post event discussion affects younger and older adults in a similar way
Evaluation of Gabbert et al. (2003) -ve:
- lacks ecological validity
- Ps knew they were taking part in an experiment
- they therefore are more likely to have paid close attention to the details of the video clip
- the results do not reflect real life where witnesses may be exposed to less info
What is anxiety?
- a state of apprehension, uncertainty, and fear resulting from a threatening situation
- when anxiety is high it can often impair both physical + psychological functioning
- several psychologists have suggested that the anxiety that occurs when witnessing a crime can prevent accurate and detailed recall of that crime
What is the weapon focus effect? (anxiety)
- the presence of a weapon during a crime increases anxiety
- this could impair witnesses’ memory of the crime
- people who observe a violent crime will often pay attention to the aspect of the situation posing the most threat to them due to the anxiety these weapons cause
- means that witnesses who see a violent crime involving a weapon can often describe a
criminal’s weapon in great detail but can’t recall much about the criminals themselves
A, Procedure of Loftus (1979)?
- wanted to see whether anxiety affected a person’s ability to recognise the perpetrator of a crime
- in experimental condition ps overhear a heated and hostile argument between two people
- also heard the sounds of furniture being overturned + broken glass
- then a man emerged carrying a letter opener covered in blood
- in control condition ps overheard a conversation between two people about lab equipment failure before a man with grease all over his hands emerged carrying a pen
- ps were then asked to identify the
person they had just seen from 50 photos
A, Findings of Loftus (1979)?
- only 33% of ps in bloody letter opener condition recognised the photo of the person carrying the letter opener
- 49% of ps in pen condition recognised the photo of the person carrying the pen
- Loftus argued that this occurred because people in the former condition had focused on the bloody letter opener rather than the
person carrying it - as the letter opener was a weapon that could pose a threat to them
Evaluation of Loftus +ve:
- study is supported by other research studies
- Loftus & Burns (1982) assigned ps to one of two conditions
- one group watched a violent short film where a boy was shot in the head
- other group watched a non-violent short film of a crime
- ps were less accurate in recall when they
saw the short film with a gun than those who watched the non-violent movie
Evaluation of Loftus -ve:
- study lacks ecological validity
- although they were waiting in the reception area outside of the laboratory, they may have anticipated that smt was going to happen
- could have affected the accuracy of their
judgments + the validity of the study
= study violated numerous ethical guidelines
= ps were deceived about nature of the experiment + not protected from
psychological harm
= ps were exposed to a man who they were led
to believe had just killed someone, holding a bloodied knife, could have caused them extreme distress
= ps may have left the experiment feeling exceptionally stressed, especially if they, or someone they knew, had been involved in knife crime - Yuille and Cutshall (1986) investigated the effect of anxiety in a real life shooting, in which one person was killed and another person seriously wounded
- 21 witnesses originally interviewed by investigating police and 13 of these
witnesses, aged between 15 and 32, agreed to take part in Yuille and Cutshall’s follow-up interview five months later - witnesses were accurate in their eyewitness accounts five months later and little change was found in their testimony
- furthermore, the witnesses avoided leading questions and those who had been most distressed at the time of the shooting gave the most accurate account
- in real cases leading questions and anxiety do not affect the accuracy of eyewitness testimony the same way they do in the lab
= are individual differences in how anxiety affects memory
= some people actually have better recall when they are anxious
= Christianson and Hubinette (1983) conducted a research study using 110 real life eyewitnesses who had witnessed one of 22 bank robberies
= some were onlookers and some were bank
clerks who had been directly threatened by the robbers
= was found that victims were more accurate than onlookers in their description of the bank
robbers
Who criticised the standard interview + why?
- Fisher et al. (1987) studied real police interviews over a four-month period and found that questions were brief, direct, fact-based and closed
- witnesses were often interrupted and not allowed to expand upon their answers
- this was referred to as the standard interview
- Fisher et al. (1987) argued that this might be contributing to the failure of eyewitnesses to accurately recall the event they had witnessed
Who developed the cognitive interview + why?
- Geiselman et al. (1985) developed the cognitive interview
- in order to improve police interview techniques and obtain more accurate info from eyewitnesses
What are the main stages of the cognitive interview?
- there are 4 main stages
1. context reinstatement - witness tries to mentally recreate an image of the situation
- including details of the environment, such as the weather conditions and their emotional state, including their feelings at the time
of the incident - these may act as retrieval cues (context-dependent
cues) to improve recall
2. report everything - interviewer encourages the witness to recall all
details about the event, even though these details may seem to be unimportant - may highlight details that have been overlooked and
trigger other memories
3. recall from changed perspective - witness tries to mentally recreate the situation from different points of view, e.g. describing what
another witness present at the scene would have seen - promotes a more holistic view of the event which might enhance recall and reduce the influence of schemas
- schemas are mental structures of preconceived idea
4. recall in reverse order - witness is asked to recall the scene in a
different chronological order, e.g. from the end to the beginning - this should verify the accuracy of the witnesses’ account and reduce the possibility that recall may be influenced by schemas/expectations