Factors affecting the accuracy of Eye Witness Testimony Flashcards
(46 cards)
Eyewitness Testimony (EWT)
Legal term. Evidence provided in court by a person who was present at the time a crime took place.
What are two factors that affect Eyewitness Testimony.
Misleading information (leading questions and post event discussion) and anxiety.
Misleading information
Incorrect information given to the eyewitness usually after the event has taken place. This can be in the form of leading questions or post event discussion.
What did Loftus and Palmer aim to investigate?
the effects of misleading information (in the form of leading questions) on the accuracy of eyewitness testimony.
What method did Loftus and Palmer use to investigate the effects of leading questions?
Took place in a lab with 45 students. They were each shown 7 films of different car accidents. Participants were given a questionnaire to describe the the accident. This included a CRITICAL question about ‘how fast were the cars going when they ‘HIT’ each other? Other groups ‘hit’ would be replaced by ‘smashed’ ‘collided’ or ‘contacted’. The mean speeds were then calculated for each condition.
What was the mean score for ‘smashed’?
40.8 mph
What was the mean score for ‘collided’?
39.3 mph
What was the mean score for ‘bumped’?
38.1 mph
What was the mean score for ‘hit’?
34 mph
What was the mean score for ‘contacted’?
31.8 mph
What did Loftus and palmer find in their study on leading questions?
REWORD THIS QUESTION
It was concluded that misleading information in the form of leading questions can indeed affect the accuracy of eyewitness testimony and that it may even cause the information to be changed before it was stored so that memory is permanently affected.
Strength of leading question research: high degree of control over variables
This means that the study was conducted in the controlled environment of a laboratory, all potential extraneous variables could be easily controlled. For example, Loftus and palmer could ensure lighting and noise levels whilst viewing the films was the same. This is a strength because it gives the research high internal validity meaning the experiment will have measured what it intended to measure.
Strength of leading question research: Loftus and palmer’s findings have practical applications
This means that the findings may be used to warn the criminal justice system about the potential problems with eyewitness evidence.
For example, juries could be warned against fully trusting evidence given by an eyewitness, however the eyewitness may be, and take into account more of a range of evidence when making decisions. This is positive as it may help to avoid inaccurate judgements being made in court.
Weakness of leading question research: using students as a sample may be unrepresentative.
This means that all of the participants in the research were one the of person who are not generally representative of the population. For example, students may be of above average intelligence.
This is problematic as the results could be said to lack ‘population’ validity as the findings cannot be generalised to everyone in society.
Weakness of leading question research: Research lacked ecological validity
This means that the study is conducted in the controlled setting of a lab and this does not reflect EWT in real life.
For example, the studies do not represent the experience of witnessing a realise car accident in the street and may also lack the fear or emotion present in eyewitness events of this kind.
This is a problem as the findings cannot be generalised to real life settings and real life EWT.
Weakness of leading question research: Yuille and cutshall 1986
It was found that 4 months after a real life robbery in Canada the 13 witnesses were not affected by two leading questions and gave the same respeonces they had given in their initial reports straight after the robbery.
It was concluded that misleading information does not affect real life EWT, possibly due to the level of anxiety and emotion experienced in real life.
This is a problem because it adds further weight to the view that Loftus and Palmer’s findings do not generalise to real-life EWT because the lab conditions lack the emotion of real life EWT.
What did Gabbert et al aim to investigate
Test the effects of post event discussion has on the accuracy of EWT.
What method did Gabbert et al use to investigate the effects of post event discussion?
- 120 participants in pairs
- Shown the same video from different POV meaning each could see different elements of the video
- For example one could see the title and one could see her commit a crime
- Then both discussed what they had seen
How many participants mistakenly reported aspects of the video that didn’t actually take place?
71%
How many participants reported the crime which they didn’t see take place?
60%
What did Gabbert et al conclude?
Witnesses often go along with each other due to MEMORY CONFORMITY - going along with the testimony of others either to win their social approval or because they believe the other witnesses are right and they are wrong.
What percentage of participants in the control group mistakenly recalled information?
0%
Strength of research into post event discussion: easy to replicate
This means that the study was conducted in the controlled environment of of a laboratory, using a video of a crime, it is easy to repeat the study in the same way over and over again.
For example, Gabbert et al could show the same video in the same conditions.
This is positive as it means the findings can easily b tested for reliability (ie consistency)
Strength of research into post event discussion: Bodner et al
They found similarly strong effects of post event discussion on the accuracy of EWT. However they also found that these effects could be reduced if participants could be warned about the negative effects of listening to second hand information from other witnesses.
This is positive because it supports the idea that memory conformity has a strong influence on EWT. accuracy.