Eye Witness Testimony Flashcards
Define EWT
The evidence provided in court by someone who has witnessed a crime, with a view to identifying it’s perpatrator
What is a leading question?
A question that, either through it’s form or content, suggests to the witness what answer is desired or leads him/her to that desired answer.
What is misleading information?
Supplying info that may lead to a witness’ memory for a crime being altered
What are the four key factors affecting eye witness testimony?
- Misleading information
- Leading questions
- Post-event discussion
- Anxiety/adrenaline
What was the aim of Loftus and Palmer’s (1974) study?
To investigate whether language used in EWT can alter memory
Loftus and Palmer (1974) - What procedure was used?
Experiment 1
45 American students from Uni of Washington formed an opportunity sample
LAB EXPERIMENT with INDEPENDENT MEASURES and five conditions
7 films of traffic collisions shown with durations of 5-30 seconds were shown to ppts in a random order
Asked specific questions including “About how fast were the cars going when they smashed/collided/bumped/hit/contacted each other?
IV = wording used DV = speed reported by ppts
What were the findings and conclusions? (Loftus and Palmer 1974)
Experiment 1
Smash condition reported the highest speeds (40.8mph)
Contacted reported the lowest speeds (31.8mph)
Conclusion = Verb used conveyed an impression of the car’s speed, altering the ppt’s perceptions
What was the procedure for Loftus and Palmer (1974) experiment 2?
150 students
Shown a one minute film with a car driving though the countryside and then 4 seconds of a multiple traffic accident
2 conditions + 1 control
Conditions involved one asking about speeds when cars “hit” and the other about when they “smashed”
1 week later without re watching the video they were asked 10 questions with one being if they saw broken glass in the video ( there was none)
16 ppts in smashed condition said they saw it compared to 7 and 6 people in the hit and control conditions respectively
What were the conclusions of experiment 2 in Loftus and Palmer (1974)?
The research suggests that memory is easily distorted by questioning technique and info acquired post event can merge with the original memory causing inaccuracies.
This also suggests its also not solely about response-bias
What were the aims of Johnson and Scott’s (1976) study?
To see how anxiety can effect recall due to weapon focus
What procedure was used in Johnson and Scott (1976)?
Ppts thought they were going to be in a lab study and were seated in a waiting room.
They would hear an argument in the next room.
In one condition a man walked in with a paper knife and bloody hands with the sound of broken glass before his entry
Other condition man walked in with a pen and grease on his hands
Thus was an INDEPENDENT MEASURES design
Findings of Johnson and Scott (1976)?
After being shown a set of 50 photos:
49% in low anxiety recognised him
33% accuracy in knife condition
Tunnel theory argues witness’ attention narrows to focus on a weapon (source of anxiety)
Possible AO3 points for Johnson and Scott (1976)?
Good - Independent measures reduced order effects
Bad - Morally questionable due to high anxiety scenario
What are the components of EWT?
Report everything
Mental reinstatement
Change order
Change perspective
What was Pickel (1998) interested in?
Whether it is threat or the unusualness which causes weapon focus
