EWT

• A cognitive interview is a police technique used to interview witness to a crime
• The 4 components of the cognitive interview are: report everything , resinate the context, change the order, change the perspective
• The factors effecting eyewitness testimony are anxiety and misleading information
• The 2 explainations for anxiety effecting memory are that it has a negative and positive effect on memory
• Loftus and palmer investigated the effects of leading questions on EWT and found that participants who were told 'collided' said the car was going 31.8mph and participants who were told 'smashed' said cars were going 40.5 mph. Shows that leading questions effects EWT accuracy
• yullie and cutshall found that anxiety had a positive effect on EWT accuracy. participants who reported high levels of anxiety were 88% accurate on their recall of a shooting in a gun shop than those who reported low levels of anxiety who were 75% accurate
• in Loftus and palmer's study, participants who heard the word 'smashed' were more likely to report seeing broken glass in the clip - but there was none - supporting the substitution explanation which suggests that changing the wording of leading questions can change the participant's memory
• gabbert et al studies the effect of post event discussions on memory and found that 71% of participants recalled information of the event that they had not seen in the video but had picked up during the discussion - when there was no post event discussion, the figure was 0% - evidence for memory conformity
• 2 explanations as to why post event discussions effect EWT:

  memory contamination - when co-witnesses to a crime discuss it with each other, their testimonies may be distorted - because they have combined misinformation from another witness with their memory

  memory conformity - gabbert concluded that witnesses often go along with each other either to gain social approval or because they believe other witnesses to be correct
• strength of using the cognitive interview - meta-analysis research has shown when the cognitive interview is used, there is a 41% increase in the accuracy of information given by the witness - suggesting it is an effective technique in helping witness recall
• post event discussion/contamination is when the recalling of events from one witness alters the accuracy of another witnesses recall- sometimes through memory conformity
• one theory of the effect of anxiety on recall is that it decreases accuracy - e.g- weapon focus effect, suggests weapons are the cause of anxiety as witnesses are distracted, focusing on the weapon rather than the criminal's appearance
• another theory of the effect of anxiety on recall is that it increases accuracy - when a person is anxious they are more alert and aware of their surroundings
• johnson & scott - naive participants placed outside a lab waiting for the 'experiment' to begin, when in fact it already had. half of the participants overheard a conversation about equipment failure and then saw a man walk out with a greasy pen. the other half heard a hostile conversation with breaking glass and then saw a man walk out holding a bloody knife. - more participants correctly identified the man with the pen (49%) than the man with the knife (33%) - due to weapon focus effect