EWT Flashcards
What is the classic study for criminological psychology?
Loftus and Palmer (1974)
Two lab experiments in one study to investigate the effects of leading questions.
State the aim for Loftus and Palmer’s study experiment 1
To see if leading questions affected recall of a car collision.
State the aim for Loftus and Palmer’s study experiment 2
To see if leading questions affected recall of broken glass which was not present in the film clips shown.
State 4 procedure points for Loftus and Palmer’s study experiment 1
45 pps were asked to view seven film clips of different car accidents in different orders.
Each film lasted 5 -30 seconds and 4/7 were staged accidents.
After each film pps were asked to give a description of the accident and asked to complete the same questionnaire on the film but with a different critical question about the speed the car was traveling.
The critical question the pps were asked was “how fast was the car going when it either smashed, hit, bumped, collided or contacted into another one.
State 2 results for Loftus and Palmer’s study experiment 1
The average speed estimated by pps was affected by the verb used.
Smashed - 40.8 mph Contacted - 32.8 mph
The stronger the word, the higher the estimated speed was.
State two strengths of Loftus & Palmer’s study
👍🏼Reliable as it was a lab experiment with control over variables. All pps watched the same film, in the same environment and were asked identical questions, accept for the critical question which was manipulated. The standardised procedure made the study replicable as it can be repeated accurately.
👍🏼Practical applications as the findings can help the police to improve the effectiveness of EWT. The police should not use verbs that imply a direction for a response or open ended questions should be used to prevent misleading the witness.
State two weaknesses of Loftus & Palmer’s study
👎🏼Lacks ecological validity as the study was conducted in a lab which is an artificial environment for EWT recall. Real witnesses experience an event in natural surroundings with uncontrolled variables. The behaviour of pps may not be as life like when they are aware of taking part in a study. Real witnesses would be more considered in their answers because they may influence a police investigation or courtroom decisions, there were no real consequences for the pps in the study.
👎🏼Low generalisability as the study was unrepresentative as it only used undergraduate students. Students may have limited experience of driving and estimating car speeds and therefore may have been susceptible to leading questions. This makes the sample biased as students do not represent the views of the wider population, suggesting it is unlikely that we can generalise beyond the sample and to all witnesses.
State a conclusion of Loftus & Palmer’s study
The study was groundbreaking at the time in that it revealed how question wording can undermine the reliability of EWT.
However the study lacks validity because the nature of the task lacks mundane realism because real life EWT does not involve watching artificial videos that one is prepared to watch.
What is the key question for criminal?
Is eyewitness testimony reliable?
State 4 description points for the criminal key question
EWT refers to the recalled memory of a witness to a crime or incident. This is recorded in a police statement or given as verbal testimony to be used in a court of law. They may also be asked to identify a suspect from a line up and testify in court.
EWT can have important consequences as it can help secure a conviction someone who is guilty of crime. However if the account is unreliable then there may be a miscarriage of justice.
A lot of weight and credibility is given to EWT and some people believe jurors are more likely to rely on EWT than scientific proof or forensic evidence.
According to research evidence since the 1990s, of the 239 convictions that were overturned because of DNA evidence, 73% were based on EWT.
Explain why EWT can be unreliable due to effects of post event information and time delay
Eye witnesses are often interviewed over a period of time before a case may go to trail. In this interim period a witness may not always give reliable information as post event information from lawyers, the media etc can confabulate the information that has already been encoded.
The reconstructive theory of memory suggests that memory is not like a tape recording that cannot be altered. It argues that we use schemes to guide our memories. Post event information can be incorporated into a memory which then become reconstructed.
Loftus and Palmer’s lab experiment showed that misinformation in the form of misleading post event questions can influence someone’s EWT. Students judged the speed of a car involved in an accident as being faster when the car described as ‘smashing’ into another car rather than being described as ‘contacted’.
Explain why EWT can be unreliable due to weapon focus
A weapon can lower eyewitness accuracy because it creates a heightened stress arousal which assists the eyewitness in recalling information about the weapon, but to the detriment of other details within the situation.
Also because the witness focuses their attention on the weapon which is threatening and unusual it lowers accuracy and reliability.
Thus other details are not encoded/paid attention to.
Loftus et al found that pps in the gun condition were less able to identify the customer in a 12 person line up than those in the cheque condition.
Explain why EWT can be unreliable due to stress and arousal
Yerkes-Dodson law suggests that there is an optimum level of arousal that helps recall but if we become to stressed or to relaxed about an event recall accuracy declines.
Loftus found that pps who watched a film of a fire had poorer recall than pps who watched a film of a less emotional event.
Explain why Yuille & Cutshall’s study supports EWT being reliable
The field study shows that post event information and time delay may not undermine the reliability of EWT.
They found 4 to 5 months after a real life gun store robbery pps were equally accurate in both police and researcher interviews. This shows that post event information might not affect memory of a real life event as much as lab experiments suggest.
Explain why cognitive interview supports EWT being reliable
The use of cognitive interview by police leads to more reliable EWT.
Police ask the witness to recall events in an unusual order e.g. Backwards or use a reconstruction of the event to aid the recall. This suggests that testimonies can be an accurate and a reliable measure of events.
