misleading information (eyewitness testimony)

• Lotus and Palmer, leading questions (procedure)

  • 45 participants (students) watched film clips of car accidents are then answered questions about speed
  • Critical question = ‘about how fast were the cars going when they hit each other?’
  • Five groups of participants, each given a different verb in the critical question
  • Hit, contacted, bumped, collided, smashed
• Lotus and Palmer, leading questions (Findings/conclusions)

  • The verb ’contacted’ = produced a mean estimated speed of 31.8 mph
  • The verb ‘smashed’ = produced a mean estimated speed of 40.5 mph
  • The leading question (verb) biased eyewitness recall of an event
  • The verb ‘smashed’ suggested a faster speed of the car then ‘cointacted’
• why do leading questions effect EWT?

  • response-bias explanation = wording of a question has no enduring effect on an eyewitness‘s memory of an event, but influences the kind of answer given
  • ‘Smashed’ made them say a higher speed
  • Substitute explanation = wording of a question does affect eyewitness memory, it interferes with the original memory, distorting its accuracy
  • Those who heard ‘smashed’ were more likely to report seeing broken glass
• Gabbert et al, post-event discussion (procedure)

  • Paired participants watched a video of the same crime, but filmed so each participant could see elements in the event that the other could not
  • Both participants discussed what they had seen on the video before individually completing a test of recall
• Gabbert et al, post-event discussion (findings/conclusions)

  • 71% of participants wrongly recalled aspects of the event they did not see in the video but had heard in the discussion
  • Control group = there was no discussion and no subsequent errors
  • Evidence of memory conformity
• why does post-event information affect EWT?

  • Memory contamination = when co-witnesses discuss a crime, the mix (mis)information from other witnesses with their own memories
  • Memory conformity = witnesses go along with each other to win social approval or because they believe the other witnesses are right
• strength = RWA in the criminal justice system

  • The consequences of inaccurate EWT are serious
  • Loftus = argues police officers should be careful in phrasing questions to witnesses because of distorting effects
  • Psychologists are sometimes expert witnesses in trials and explain limits of EWT to juries
  • => psychologist can improve how the legal system works and protect the innocent from faulty convictions based on unreliable EWT
• counterpoint to RWA in justice system

  • Loftus and Palmer showed film clips:
  • a different experience from a real event (less stress)
  • Participants are also less concerned about the effect of their responses in a lab study
  • => low external validity
  • => researchers may be too pessimistic about the effects of misleading information - EWT may be more reliable than studies suggest
• limitation = substitution explanation has evidence challenging it

  • Sutherland and Hayne = found their participants recalled central details of an event better than peripheral ones, even when asked misleading questions
  • This is presumably because their attention was focused on the central features and these memories were relatively resistant to misleading information
  • => the original memory of the event survived and was not distorted, which is not predicted by the substitute explanation
• limitation = evidence does not support memory conformity

  • Skagerberg and Wright = participants discussed film clips they had seen (in one version the mugger had dark brown hair, the other had light brown hair)
  • The participants recalled a ‘blend’ of what they had seen and what they had heard from their co-witness, rather than one or the other (eg said hair was ‘medium brown’)
  • Suggests that the memory itself is distorted through contamination by post-event discussion and is not the result of memory conformity
• extra evaluation = demand characteristics

  • Lab studies give researchers high control over variables (high internal validity) so they can demonstrate that misleading post-event information causes inaccurate EWT
  • BUT = lab experiments suffer from demand characteristics
  • Participants want to help so they guess when they can’t answer a question (low internal validity)
  • => to maximise internal validity researchers should reduce demand characteristics by removing the cues that participants used to work out the hypothesis
• limitation = deterministic

  • Theory claims that misleading information WILL lead to distorted memory
  • doesn't take into account individual differences