Booklet 2: Eyewitness Testimony Flashcards
What is eyewitness testimony?
Evidence supplied by people who witness a specific event/crime, relying on their memory.
What is the delvin report?
The psychological study of the accuracy of eye witness recall suggests that it is actually far less reliable than we might imagine. The importance of this issue was highlighted in the Delvin report (1976) which found that in a large proportion of criminal cases, eyewitness testimony was the only eveindece offered in court, and in 75% of these cases the suspect was found guilty. However research in the USA has shown that there may be as many as 10,000 wrong convictions in a year, showing that eyewitness testimony is not reliable.
Who is Elizabeth Loftus?
The leading researcher in EWT. She claims that a persons memory of crime is affected by many things.
What is misleading information?
Often found in form of a question- using words to wrongly imply something has happened so that a witness gives a false testimony. e.g. leading questions.
Describe the procedure of research into misleading information. (Loftus and Palmer)
An sample of 45 american students took part in a lab experiment in which there were 5 conditions (an independent measures design) The were shown a series of 7 films of car accidents. Students were then given a questionnaire about the accidents, which included one specific question about the speed of the cars. Each condition answered a different question ‘How fast were the cars going when they …… each other?’ The blank was filled with either the word smashed, collided, bumped, hit, contacted. A week later the participants were also asked if they had seen any non existent broken glass.
Describe the findings of research into misleading information (loftus and palmer)
They found that the condition that used the word smashed led participants to estimate the highest score of 40.8. The participants that were asked with the word contacted estimated the lowest speed of 31.8. A week later they also found that 16% of the participants in the smashed condition had mistakenly seen broken glass, which was considerable more than any other group.
What did loftus and palmer conclude in their research into misleading information?
They concluded that leading questions have a significant effect on eye witness testimony as even if only one word is changed, it will significantly change a persons recall.
What are the main criticisms of research into misleading information?
The main criticism relates to the unrealistic setting and situation of the lab experiment, which could lead to a number of issues:
- Lack of emotional arousal as its not a real life car crash, it was a video which therefore doesn’t create the same emotion as a real crash. In this situation the lack of emotion would make the participants feel less pressure to get the answer right.
- Lack of usual distraction in real life EWT as the participants were waiting for the video to be played. In real life you would wait for a crash to happen so your full attention wouldn’t be focused in the same way.
- Possibility of demand characteristics as the participants were away they were being studied. Therefore we are unable to see if the results are because of the verbs being changed or because they knew the aim of the study.
What is another problem with the research into eyewitness testimony?
There are problems with the generlisability of the sample as they are all american students so don’t represent the entire population. Secondly because they are students, they are less likely to be drivers so are therefore easier to be lead than the average adult. However the research does have a number of important practical implications for real life EWT as it has been used to change the judges system and the way in which witnesses are questioned.
What is the effect of anxiety on EWT?
Anxiety is often associated with witnessing real life crimes and can seriously impact on recall of important features of the situation.
Explain the Yerkes-Dodson inverted U hypothesis.
This has been used to explain how anxiety can affect accuracy of EWT. It shows that a moderate amount of anxiety increases the accuracy of memory up to a point, but after that further anxiety leads to a decline in accuracy.
What is Freud’s explanation of anxiety on EWT?
He suggests that it is an ego defence mechanism where the content of traumatic memories is repressed as a way of protecting the mind from emotional stress.
Explain the procedure of research into the effect of anxiety on EWT (Loftus et al - the weapon focus effect)
Loftus suggested that if there is a weapon present at the scene of a crime it may distract attention away from other aspects of the situation. She conducted a lab experiment to test this.
Participants were left in a waiting area outside a laboratory whilst waiting for the real study to start. While they were waiting one of two situations occurred:
- They overheard a low key discussion in a lab about equipment failure. A person then emerged from the lab holding a pen with grease on his hands.
- They overheard a heated discussion between people in a lab. After the sound of breaking glass and crashing chairs, a man emerged from the lab carrying a knife with blood on his hands.
The participants were asked to identify the man from a series of photos.
What were the findings of research into anxiety?
The participants in the pen condition had an accuracy of 49% which was considerably higher than in the knife condition where the participants had an accuracy of 33% in recall of the man.
What was the conclusion Loftus made in the anxiety research?
fear of the weapon narrows the witnesses attention to the weapon, thus leaving less attention for other details in the scene.