Misleading information

• Eyewitness testimony

  • Refers to an account given by people of an event they have witnessed.
  • E.g accidents, crimes they have observed themselves
• Misleading information

  • Incorrect information given to an eyewitness usually after the event, which can distort what people remember about the event.
  • 2 ways this can occur is through leading questions and post-event discussion
• Leading questions


  Questions that are phrased in a certain way to suggest a particular answer
• Examples of leading questions

  • Did you see that gun?
  • Was the knife used in the accusers left hand?
• Loftus and palmer experiment 1

  • Effect of leading questions on the accuracy of EWT
  • 45 students shown short videos of car accidents
  • All were asked ‘How fast was the car going when they….. each other?’
  • Each group was given a different verb to fill in e.g smashed, collided, bumped.
  • When smashed was used, participants estimated that the cars were travelling much faster than when the verb ‘contacted’ was used.
  • Leading questions can distort accuracy of judgements.
• Loftus and Palmer experiment 2

  • 150 Student participants shown a short film that showed a multi-vehicle car accidents and then they were asked questions about it.
  • Participants split into 3 groups.
  • How fast were the cars going when they hit each other.
  • How fast were the cars going when they smashed into each other
  • Third group was not asked about the speed of vehicles
  • One week later, all participants returned and were asked ‘Did you see any broken glass’
  • There was no broken glass
  • Verb used in original question influenced whether the participants thought they had seen broken glass.
• Why do leading questions affect EWT?

  • Response bias
  • Substitution
• Response bias

  • The different speed estimates occurred because the critical word influences or biases a persons response.
  • The persons schema for the verb influences their answer
  • Leading questions does not affect memory, just the choice of answer
• Substitution

  • The critical word changes a persons memory so they actually see the accident differently.
  • The memory has been imagined and they genuinely believe the changed.
  • The leading questions actually distorts memory.
• Post-event discussion


  Occurs when there is more than one witness to an event.

  Witnesses may discuss what they have seen with other co-witnesses or other people.
• Why is post-event discussion bad?

  • They combine misinformation from other witnesses with their own memories.
• Research for effect of post-event discussion on EWT

  Gabbert et al

  • Participants consisted of 60 students from University and 60 adults from local community.
  • Each participant watched a video from a crime scene, but filmed from different points of view.
  • Either tested individually or in pairs (co-witness)
  • Participants in co-witness group were told they had watched the same video, however they seen different perspectives of the same crime.
  • Participants completed a recall test, testing their memory of the event.
  • 71% of participants recalled aspects of the scene they hadn’t seen.
• Why does post-event discussion affect us?

  • Memory contamination
  • Memory conformity
• Memory contamination

  Memories become altered or distorted because they combine information from other witnesses with their own memories.
• Memory conformity


  Witnesses go along with each other to win social approval or because they think others are right.
• Evidence against substitution

  • Sutherland and Hayne showed participants a video clip. When participants were later asked misleading questions, their recall was more accurate for central details of the even than for peripheral ones.
  • Shows that participants paid more attention on the central features of the event and these memories were relatively resistant to misleading information.
  • Original memories for central details survived and were not distorted, an outcome which was not predicted by the substitution explanation
• Issue of demand characteristics

  • Zaragosa and McCloskey, argue that many answers participants give in lab studies of EWT are as a result of demand characteristics. For example, participants usually do not want to let the researcher down so when a question is asked they may answer yes to did you see the broken glass to appear more helpful.
  • Leading questions imply the participants need to say a certain answer. Participants may behave differently to meet the expectations of the researchers.
  • As a result of demand characteristics, internal validity decreases.
• Useful real life application

  • Loftus has found that leading questions can have such a distorting effect on memory. Recent DNA cases have confirmed the warnings of relying on eyewitnesses. Researchers have found mistaken eyewitness identification was the largest single factors contributing to the conviction of these innocent people.
  • This is useful as it informs police to not use leading questions because they can distort their account of the crime or accident.
  • Research can reduce the number of wrongful convictions and improve criminal justice system.
• Tasks are artificial

  • For example, in the study conducted by Loftus and Palmer the procedure involved participants watching film clips of a car accident,
  • This is a limitation because the tasks participants were required to do is not a reflection of witnessing them in real life. This may be due to real-life crime or accidents being more emotionally arousing which could affect accuracy of EWT
  • The research conducted lacks external validity because it cannot help explain how leading questions may influence accuracy of EWT on real life events.