Misleading information

• 3 stages of an eyewitness testimony

  • Witness encodes into the LTM the details of the event and persons involved
  • Witness retains info for a period of time - info can be lost or distorted in this time
  • Witness retrieves memory (cues or questioning may affect accuracy)
• Statistics

  • The innocence project - claim that 72% of convictions overturned by DNA testing involved EWT that was not accurate
  • The delvin report - if ewt was the only evidence available and in 75% of cases suspect found guilty therefore may lead to false convictions
  • Legal processes now require more proof
• Misleading information

  • Incorrect info given to an eyewitness usually after the event so it can distort memory (e.g a leading question )
• Loftus and palmer - experiment 1

  • Aim - see the effect of misleading information on ewt
  • 45 students were shown 7 different videos of traffic accidents then given a questionnaire to describe and then answer specific questions
  • One critical question “how fast were cars going when they hit/smashed/collided/bumped/contacted?
  • Smashed - 40.8 mph
  • Contacted 31.8 mph
  • Shows that leading questions affect recall
• Loftus and palmer experiment 2

  • Same aim as experiment 1
  • 150 participants in 3 groups and shown a 1 minute car accident and asked the same question about speed and a week later were asked 10 questions without watching the video again and one asked if they saw smashed glass
  • Group 1 - smashed (16 yes 34 no)
  • Group 2 - hit (7 yes 43 no)
  • Group 3 - no question about speed (6 yes 44 no)
• Bias

  • Response bias - the wording of the questions has little effect on the memory but does influence how we decide to answer
  • Substitution bias - the wording of the question changed the participants memory of the event
• Gabbert et al

  • Aim - to investigate the effect of post event discussion on ewt
  • Participants put in pairs and each watched videos of the same event but from a different point of view meaning some saw unique elements of the events that others didn’t
  • Pairs were encouraged to discuss the event before each partner individually recalled the event they watched
  • Results - 71% of witnesses who discussed the event mistakenly recalled items acquired during the discussion but with no discussion it was 0%
• Repeat interviewing

  • Each time an eyewitness is interviewed there is the possibility that comments from the interviewer will become incorporated into their recollection
  • LaRooy found that this is especially true for children witnesses
• Memory conformity and contamination

  • Conformity - witnesses go along with others for social approval or because they think others are right (memory not changed)
  • Contamination - co witnesses mix/miss info from others and their own (memory is changed)
• Strengths

  • Real world application - info led into developing the cognitive interview and creating a positive effect on decreasing wrongful convictions
  • Loftus - college students were asked to evaluate advertising material about Disneyland, they had all been to Disneyland in the past. She embedded bugs bunny, Ariel or none in groups (bugs not Disney and Ariel wasn’t made at the time). In the character conditions they were likely to recall shaking hands with characters