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• Memorise these words, you have until I have finished reading them out.
sour nice candy
honey sugar soda
bitter chocolate good
heart taste cake
tooth tart pie
• Look at your list – Who wrote down the word ‘Sweet’?
• You have experienced a false memory!!• Key Study: - Loftus & Palmer• How is this relevant to Eyewitness Testimony?• Why is it an issue?• http://www.youtube.com/watch?
v=XcywPdORySA&feature=relmfu• Memory is prone to distortion and inaccuracies!
EWT
objectivesYou will learn about the Loftus and Palmers (1974)
studies into EWTYou will be able to critique the technique and the
research.You will be able to apply this knowledge to exam
style essay questions
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Eyewitness Testimony
What is it?The legal term referring to the use of eyewitnesses to give evidence in court concerning the identity of someone who has committed a crime.
Eyewitness Testimony
Eyewitnesses play a role in criminal investigations.The psychological study of the accuracy of EWT suggests it is not reliable.
The Devlin Report (1976) EWT was the only evidence offered in court and in 75% of these cases the suspect was found guilty.Research in the US has shown that eyewitness memory is the main factor leading to false convictions!
http://www.youtube.com/watch?v=u-SBTRLoPuo
Our Memory can be affected by…
• Schemas (Reconstructive memory)• Age of Witness• Anxiety• Post event information • Leading Questions
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Studies into the accuracy of EWT
• Loftus and Palmer (1974)
• http://www.youtube.com/watch?v=mSBbTTiXgdM
• You are about to take part in a study on memory. You will be shown a video of a car crash. During the experiment, please do not talk to each other.
Loftus and Palmer (1974)
At what speed do you think the on-coming car was travelling when the cars crashed?
Smashed collided bumped hit collided
The aim of this was to find out leading questions distorted the accuracy of an eyewitnesses recall
Star Study: Loftus and Palmer (1974)
Findings: The mean speed varied significantly between groups.
‘smashed’ – approx 41mph, ‘collided’ – approx 40mph, ‘bumped’ – approx 38mph, ‘ ‘hit’ – approx 34mph, ‘contacted’ – approx 32mphConclusion: Leading questions (post-event info) can
have an effect on memory.
Loftus and Palmer 1974
• Read the info on Loftus and Palmers study• You need to complete the boxes around the
outside you need to consider
• AO1-Procedure and findings• AO2- Criticisms• AO3-Methods used, IV, DV etc
Conclusions of Loftus and Palmer’s study
• EWT is generally inaccurate• Not all agree…
• Yuille & Cutshall (1986) examined the recall of witnesses to a shooting in a town in Canada. They interviewed 15 witnesses 3 months after the event and found that:-
• 1. witnesses recalled great detail, • 2. high level of agreement between accounts and • 3. witness accounts did not alter in response to leading
questions!• This goes against Loftus’ theory on reconstructive memory
– HOW?• Yuille & Cutshall study has high ecologically validity – WHY?
The role of Post event information in EWT
• Loftus and Palmer did a second study to see if information after an event can affect EWT.
• Read the info and then complete the worksheet for Loftus and Palmers second study.
Loftus’ 2nd experiment (Broken glass study)
To see if post event info alters memory• Loftus (1975) – Showed 2 groups a film of a car
accident. More participants remembered a non-existent broken headlight in the group that were asked – ‘Did you see the broken headlight?’, rather than ‘Did you see a broken headlight?’
• Gave higher estimates and more likely to say they saw broken glass
Conclusions Leading questions introduce new infoActivate wrong schemas in witness’ mind
Evaluation AO2 of Loftus’ research: link to research methods.
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Laboratory Experiment
Validilty Artificial
Ecological Validity
Demand characteristics
Loftus and Palmer (1974)
Criticisms: Validity-May not be true to life because ppts may not take the
task seriously and thus behaviour does not represent real EWT. Loftus has made a huge contribution to our understanding of
EWT and her research is rigorous. Participants all students – not a representative sample. They might have guessed what was expected – demand
characteristics.
Real eyewitnesses are likely to be emotionally affected and know their testimony could have serious consequences. (Foster et al (1994) – witnesses more accurate in recalling memory of a bank robbery when they were led to believe their testimony would influence a real trial.)
Some research has shown that if circumstances are right then witness recall can be very accurate such as Yuille & Cutshall (1986)
Implications
• Loftus says that EWT are little more than guesses. These findings were highly influential in the writing of The Devlin Report, which concluded that, unless circumstances were highly unusual, EWT should not result in a conviction in an English court in the absence of other evidence!
Exam Questions1. When police question eyewitnesses it is easy to unconsciously ask
questions that may “lead” the eyewitness to give predictable answers. This is misleading information
a) Give an example of such “misleading information” (2 marks)b) Explain why misleading information is a problem for police (2marks)
interviews
2.Describe one study of the effects of misleading information on EWT (6 marks)3. Explain one threat to the validity of the study you described above (3 marks)
4. Outline and evaluate research on the effect of misleading information on EWT (12 marks)
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Plenary
• Have you learnt about Loftus and Palmer’s research?
• Are you able to critique the technique and the research?
• Can you apply this knowledge to exam style essay questions ?
• Write down one thing you have learnt this lesson on the post it note.
