EWT

• Eyewitness testimony (EWT)

  An account of an event or crime that was seen by an observer firsthand
• Eyewitness testimony may be unreliable, and affected by factors such as anxiety and post event information
• Post event information

  Any information supplied to an eyewitness after the event that may affect their recall
• Post event information

  • Leading questions
  • Postevent discussion
• Weapon focus


  When eye-witnesses attention is drawn towards the weapon a perpetrator is holding, which results in them being less able to recall other details of a crime
• Post event information refers to any information that arrives after an event that may affect or distort eyewitnesses' memory of what happened
• Human memory is reconstructive - memory doesn't record events in exact detail, like a camera
• A person's ability to recall the events of a crime may be based more on their schema of the event than what actually occurred
• Effort after meaning

  Bartlett's term for how memory fits memories within pre-existing frameworks of expectations and past knowledge
• Post event discussion

  1. Witnesses talk to each other following the event

  2. Accuracy of eyewitness accounts depends on this
• 71% of participants referred to details they could not have seen in the video and must have picked up as part of the discussion
• Leading questions

  Questions or statements that lead a person to a specific answer
• Leading questions can trigger schemas and provide post event information that affects eyewitness recall
• Anxiety

  Stress can affect the way eyewitnesses encode memories at the time of the crime
• Moderate levels of anxiety are helpful to memory, but extreme anxiety is associated with a decline in recall
• Weapon focus

  The brain's natural tendency to zoom in on a weapon as the main source of stress, leading to forgetting or misremembering other details
• Tunnel theory

  Noticing a weapon produces a form of selective attention which excludes or ignores any other competing bits of information
• The effect of leading questions has been demonstrated under laboratory conditions
• Leading questions


  • Participants who heard the word "smash" gave higher estimates of speed compared to "contacted"
  • Participants who heard "smashed" were more likely to report seeing broken glass
• Evidence from real crimes does not support the effects of leading questions after weapon focus (anxiety)
• Witnesses to a real-life shooting produced accurate accounts despite the inclusion of leading questions
• The effects of leading questions and weapon focus may be less pronounced when applied to real-life events
• Weapon focus explanation

  • Supported by experimental evidence
  • Participants in control condition were better able to identify the man they saw compared to weapon condition
• Weapon focus may be related to surprise as much as anxiety
• Eyewitness research has led to the introduction of social framework evidence in legal cases
• Psychologists may be called upon to provide context to juries on the unreliability of eyewitness testimony
• Laboratory studies of eyewitness testimony exercise a high level of control but can never replicate the anxiety of a real life event
• Research needs to include real-world observations to support the findings of laboratory studies