Factors affecting accuracy of eyewitness tesco

• Leading question


  A question that may lead or mislead a witness to give a certain answer
• Police questions may lead a witness to give a particular answer in eyewitness testimony (EWT)
• Experiment by Loftus and Palmer (1974)

  1. Participants watched clips of car accidents

  2. Asked questions about the accident using different verbs (hit, contacted, bumped, collided, smashed)

  3. Mean estimated speed calculated for each group
• The leading question biased the eyewitness's recall of the event
• Response-bias explanation


  The wording of the question has no real effect on the participants' memories, but just influences how they decide to answer
• Substitution explanation


  The wording of a leading question changes the participant's memory of the film clip shown
• Experiment by Gabbert et al. (2003)


  1. Participants in pairs watched a video of a crime from different viewpoints

  2. Discussed what they saw before individually completing a recall test

  3. 71% of participants mistakenly recalled aspects they did not see but picked up in the discussion
• Memory contamination


  When co-witnesses discuss a crime, their eyewitness testimonies may become altered or distorted as they combine (mis)information from other witnesses with their own memories
• Memory conformity


  Witnesses often go along with each other either to win social approval or because they believe the other witnesses are right and they are wrong
• Anxiety has strong emotional and physical effects, but it is not clear whether these effects make eyewitness recall better or worse
• Anxiety creates physiological arousal

  Prevents paying attention to important cues, so recall is worse
• Experiment by Johnson and Scott (1976)

  1. Participants in low-anxiety condition saw a man with a pen and grease on his hands

  2. Participants in high-anxiety condition saw a man with a blood-covered knife

  3. Fewer participants in high-anxiety condition were able to identify the man
• Weapon focus

  Anxiety caused by the presence of a weapon leads to a focus on the weapon, reducing a witness's recall for other details of the event
• Cognitive interview (CI)


  A method of interviewing eyewitnesses to help them retrieve more accurate memories, using four main techniques: report everything, reinstate the context, reverse the order, and change perspective
• Cognitive interview (CI)


  • Based on evidence-based psychological knowledge of human memory
• Enhanced cognitive interview (ECI)


  Includes additional elements to focus on the social dynamics of the interaction, such as managing eye contact and reducing eyewitness anxiety