Eyewitness Testimony: Flashcards
The effects of leading questions on the accuracy of EWT:
-memories witnesses create at the time of an event appear to be quite fragile and subject to distortion by things that happen after the event
-consequently, serious errors in EWT can occur
-it’s been found that witnesses who encounter inaccurate information after an event can absorb this into their memory, thus distorting the actual memory of the event -> Loftus (1992) calls this “misinformation acceptance”
-research algo suggests that there is a tendency for the misinformation effect to become stronger as the time between the witnessed event and recall of it becomes greater
Loftus and Zanni (1975):
-participants were shown as brief video of a car accident and then asked a series of questions
-half of the participants were asked -> had they seen “a” broken headlight
-half of the participants were asked -> had they seen “the” broken headlight
-there was no broken headlight in the film
-17% of those asked about “the” broken headlight reported seeing one
-7% asked about “a” broken headlight reported seeing one
-those in the “the” condition -> gave fewer uncertain responses, such as “I don’t know” -> suggests they had greater confidence in memories for events that never occurred
Loftus and Zanni (1975):
-using “the” implanted the idea that there was indeed broken glass, leading some participants to change their recall accordingly
-in practical terms -> suggests that the way questions are asked following a crime can lead to innacuracies in witness recall, and brings into question the reliability of EWT
-this misinformation effect through the use of leading questions has been replicated in many studies
Loftus and Palmer (1974):
-showed 45 participants a film of a car accident
-following this they were asked to describe events as though they were witnesses
-they were then asked a serie of specific questions about events leading up to the accident
-one critical question concerned the speed of the car on impact
-one group was asked ‘How fast were the cars when they hit each other?’ Other groups of participants were asked the same question, but, in each case, the verb was changed to either ‘smashed’, ‘bumped’, ‘collided’ or ‘contacted’
Loftus and Palmer: good things and bad
-because it was a controlled laboratory experiment, the study has been accused of being artificial, i.e. the conditions of testing do not resemble those in real life so therefore the behaviour of participants is not natural behaviour
-a film clip would not have the same emotional impact as witnessing a real-life accident, and because a witness would not be prepared to observe carefully (as they were in the experiment) it could be argued that their recall of a real accident would not be as complete
-there are a number of reasons why memories are affected by leading questions
-one possibility -> due to the constructive nature of LTM, leading questions actually change a witnesse’s perception of the event -> the storage of inaccurate memory
-whether or not accuracy of eyewitness memory is influences, storage or retrieval factors around the event itself can also influence recall
Loftus (1979):
-gave participants a set of slides that showed a red purse being stolen from a handbag
-they were later given an account of the theft that included several errors, i.e. “the purse was brown”
-in a subsequent recall test, all but two of the participants resisted the misinformation about the colour of the purse, although they were influences by misinformation about less central elements of the theft
-Loftus concluded that memory for information that is particularly striking at the time of an event is less suspectible to misinformation acceptance than memory for more peripheral details
-another important factors appears to be -> the amount of anxiety caused by witnessing a crime
-it has long been established that states of high emotional arousal can influence memory functions, and a number of lab studies have demonstrated impaired memory in people who have witnessed particularly unpleasant and anxiety-inducing events
What are extraneous variables?
-extraneous variables are factors or conditions that are not the focus of a study or experiment but could influence the outcome or results if not properly controlled
-these variables can introduce noise or bias into the experiment, making it harder to determine the true relationship between the independent variable (the one being manipulated) and the dependent variable (the outcome being measured)
The importance of controlling extraneous variables:
-if extraneous variables are not controlled, they can become confounding variables, meaning they provide alternative explanations for the results
-proper control of these variables is crucial for the internal validity of an experiment, ensuring that any observed effect is due to the independent variable and not som other factor
Possible extraneous variables in research:
-variations in individual memory capacity may influence how participants recall details of the event
-previous knowledge or experiences: some participants may have prior knowledge of the event or may have been involved in similar situations, which could affect their recall
-participant attention during the event: if participants are not paying equal attention to the event being recalled, this could affect recall
-social desirability bias: participants may alter their answers to conform to what they think is “right” answer or to please the researcher
-emotional state of participants: a participant’s mood or stress levels may influence how they recall details
More possible extraneous variables:
-ambiguity in the even presented: if the event being shown to participants is ambiguous, this may influence recall
-question wording consistency: variations in how leading questions are phrased beyond the intended manipulation could introduce bias
-time delay between event and recall: the length of time between witnessing the event and being asked the leading questions may affect recall accuracy
-particpant’s age: age can affect memory recall, with younger and older participants possible recalling details differently
-environmental conditions: factors like lighting, sound, or other distractions in the environment may impact how well participants remember details
Fisher et. Al (1987):
-over a 4 month period, they studied real interview conducted by experienced detectives in Florida
-found that witnesses were frequently bombarded with a series of brief, direct and close questions aimed to elicit
-the sequencing of these questions often seemed out of sync with the witnesses’ own mental representation of the event
-witnesses were often interrupted and not allowed to talk freely about their experiences
-Fisher felt these interruptions were unhelpful because they broke the concentration of the witnesses and also encouraged shorter, less details answers
Geiselman et. Al (1985):
-> developed a technique to improve the accuracy of eyewitness recall during police investigations which they called cognitive interview
-context reinstatement (CR): mentally reinstate the context of the event, recall the scene, the weather, thoughts and feeling at the time
-report everything (RE): report every detail possible even if it seems trivial or irrelevant
-recall from a changed perspective (CP): try to describe the episode as it would have been seen from different points of view
-recall in reverse order (RO): change the order of recall so that the event is reported in different orders, moving backwards and forwards in time
The cognitive interview:
-> designed to enhance retrieval of the original memory by providing extra cues that might help jog witnesses’ memory for more central details
-subsequent research led to a version of the technique called the enhanced cognitive interview
-after looking at current police practice through detailed analysis of taped interviews, Fisher et. Al(1987) suggested adding several extra features to a more structured process
Support for the cognitive interview:
-Geiselman et. Al (1985): found that the cognitive interview resulted in more information being drawn from witnesses compared to other interview techniques
-Fisher et. Al (1989): also demonstrated the effectiveness of thecognitive interview technique in real police settings in Miami in the US
-they trained detectives to use the enhanced cognitive interview techniques with genuine crime witnesses and found that its use significantly increased the amount of information recalled
-Kebbell et.al (1999): carried out a survey of UK police officers and found that there was widespread use of cognitive interview
-Milne and Bull (2002): tested all cognitive interview procedures either singly or in combination
-they found that all 4 procedures snugly produced more recall from witnesses than standard interview techniques
-however the most effective combination appeared to be the use of CR and RE instructions, which is in line with that practising police officers had suspected
Opposition to cognitive interview:
-Kohnken et.al (1999): found that witnesses questioned using the cognitive interview also recalled more incorrect information than those questioned using the standard questioning technique
-this is possibly because the cognitive interview procedure elicits more information overall than other procedures
For Kebbell: however, while officers found it useful, they expressed some concern about the amount of incorrect recall generated and the amount of time it took to complete an enhanced cognitive interview
-in practice, it seemed like officers were using the RE and CR instructions, but rarely the CP and RO
