Eye witness testimony

Eye witness testimony

1. EWT- an account given by people of an event they have witnessed

2. Things effecting EWT

   • influence of the schema- a collection of ideas based on experience
     • reconstructive memeory- means the schema will fill in gaps within the memory
   • this reduces reliablity- not necessarily recallling 100% fact, schemas could be filling in gaps in the momories. especially if the recall is a long time after
     • consequences
       • people may get wrongly accused of crimes and go to jail or even death
   • leading questions
     • because of the way the questions are phrased suggests a certain answer. making it likley the persons schema will influence their answer

3. loftus

   • experiment one
     • METHOD: 45 uni students showed 7 clips of a car crash. the students then wrote an account of the crash and answered questions based on the cars speed.
       • 5 groups each with 9 members
         • each group got a different verb in the key question "how fast was the car going whn they crashed/bumped/tapped/hit/ collided with eachother
     • RESULTS: smashed= mean MPH 40.8 MPH contacted= mean MPH 31.8 MPH
     • CONCLUSION: misleading info in form of of leading questions can effect recall
   • experiment 2
     • METHOD: 150 students viewed a video of a car crash.
       • 50 asked the question with the words "smashed"
       • 50 asked with the word "hit"
       • control group wasnt asked
       • 1 week later the participents were asked if there was any broken glass in the video (there wasnt)
     • RESULTS
       • answer
         • yes
           • smashed 16
           • hit 7
           • control 6
         • no
           • smashed 34
           • hit 43
           • control 44
     • CONCLUSION: misleading info in the form of post event info can affect memory recall
   • AIM BOTH: to see if the speed of the car the participents estimate can be influenced by the verb
   • EVALUATE
     • LAB STUDY- artificial tasks (watching a video) lacks ecological validity. if real crash more emotion
     • DID 2 STUDIES- have more evidence to support the conclusion and they used a random selection of students, reducing bias
     • ONLY USED STUDENTS- hard to generalise. students brains may not be fully develped, so may be more influenced by leading questions.

4. post event discussion

   • when there is more than one whitness to an event. CO-witnesses can then influence the accuracy of others recall. EWT can become contaminated as info from other eitnesses can be combined with their own
   • studies
     • Gabbert (2003)
       • AIM: to investigate the effect of post event discussion
       • METHOD
         • SAPMLE: 60 students from the uni of aberdeen and 60 older people from the local community
         • participants watched a video of a girl stealing a wallet
           • individually (control group) pairs (co-witness group)
           • the participent in the co-witness group were told they had watched the same video, however they had seen it from different perspectives of the same crime. only ONE had actually witnessed the girl committing a crime. the co-witnesses were allowed to discuss what they had seen between eachother. then ALL of the participents compleated a questionnaire
       • RESULTS: 71% of the participants in the co-witness group reaclled info THEY HAD NOT ACTUALLY SEEN. 60% said she was GUILTY despite NOT SEEING HER COMMIT A CRIME. the corresponding result in the control was 0%
       • CONCLUSION: people who had discussed with the other witnesses had changed what they had origionally thought/seen. meaning that post event discussion leads to less accurate recall
       • evaluate
         • PRACTICAL APPLICATON- police can use this when talking to witness as they know to seperate the witnesses, so info isnt contaminated
         • LACKS ECOLOGICAL VALIDITY: it is artifical watching a video and dosent represent how people may react in real life with emotion ect
         • LAB STUDY- controlled and standerdized, so you can replicate the study easily, meaning the results are more replicable
     • Yuille and cuttshall
       • carried out a naturalistic study where people whitnessed a real volent shooting at a gun shop. found misleading info DID NOT distrot their memories this DOES NOT SUPPORT the study
     • loftus and zanni
       • participants who were recalling a video of an accident were asked if they saw "the" broken headlight or if they saw "A" broken headlight. the "THE" broken headlight question had a more positive response. THIS SUPPORTS the study as it shows a positive response to for the leading question using "the" not "a"

5. anxiety

   • anxiety is a state of physical and emotional arousal. emotions include: having worried thoughts and feelings of tension.
     • physical changes include increased hear rate, cryig and sweating
   • DEFFINBACHER- INVERTED U HYPOTHESIS
     • • OPTIMUM RECALL IS MODERATE ANXIETY
   • anxiety is a normal reaction to stree, but can effect accuracy of eye witness testmony
   • studies
     • peters (1988)
       • METHOD: recruted people who were going to a health care centre for a routine inoculation. they met a researcher and a nurse for an equal amount of time. One week ater the ps were asked to identify the researcher and nurse from a series of pics
         • RESULTS: people more able to identify the researcher meaning that heightend anxiety from the nurse and the injection had a negitive effect on memory
       • EVALUATE
         • NATURALISTIC STUDY: low contol of extraneous variables
         • NATURALISTIC STUDY: has more ecological validity
         • invidual differences in terms of levels of levels of anxiety
   • EVALUATE
     • PRACTICAL APPLICATION: allow witnesses to calm down before giving statments to give a more accurate recall
     • ETHICAL ISSUES: can cause actal psychological harm. cost VS benifits
     • INVERTED U TOO SIMPLISTIC: evryone performs differently and it dosnet expalin what "moderate anxiety "is. reductionist, dosent take into account other factors E.G. eotions
     • DEMAND CHARACTERISTICS: people may lie to avoid judgement or to meet the studies aim

6. COGNITIVE INTERVIEW

   • FEATURES OF CI
     • FREE RECALL: lets people talk freely and recall info even if it seems irrelevant
     • CHANGE IN PERSPECTIVE: recount the scene from different perspectives E.G. the offenders point of view
     • MENTAL REINSTATMENT: return to to the context of the crime
     • CHANGE THE ORDER: recount the scene in a variety of different chronological orders
   • studies
     • fisher (1989)
       • A: effectivness of CI
       • M: 7 experienced police detectives trained in CI technique compared to 9 untrained detectives . both recorded interviewing an eye witness before of a crime before & after training
       • R; trained 47% more than before training & 63% more than untrined overall 94% more when results collaberated
       • C: CI is more effectiv ethan SPI
   • the ENHANCED CI
     • interviewer should not distract the witness with unnecisary questions
     • witness controls flow of interview
     • get witness to speak slow
     • reduce witness anxiety
   • studies
     • HOLLIDAY (2003) showed CHILDREN ages 4-5 and 9-10 a video and used EITHER the SPI or CI to interview them the next day. the ECI was MORE ACCURATE
   • CI TAKES ALOT OF TIME TO DELIVER: free recall means you could be talking hours with no evidence
   • LOTS OF SUPPORTING RESEARCH
   • CI PRODUCES HIGHER LEVEL OF FALSE MEMORIES: free recall people over elaborate and schema
   • OUICK TO TRAIN PEOPLE: only 4-41/2 hours training more officers can do interviews at once svaing money
   • SOME BITS MORE IMPORTANT: free recall and mental reindtatment are more important. the others are confusing and waste time

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