Accuracy of Eye Witness Testimony

• Bartlett (1932)


  Argued that reconstructive memory may produce errors in accurate recalling due to schemas
• Leading Questions


  Imply answers and influence memory through substitution bias or emotional pressure in response bias
• Post Event Discussion


  Recall of 1 witness can alter accuracy of another witness, creating memory conformity
• Anxiety


  State of arousal that can decrease recall due to weapon effect; can also increase accuracy however due to alertness and the memory encoding environment
• Yerks-Dodson Law of Arousal


  EWT accuracy increases as anxiety does, but if anxiety becomes too high, it can equal more stress resulting in lower accuracy
• (+) A03: Loftus and Palmer


  Car crash clips, asking a question and changing the verb each time e.g. smashed, bumped

  • Found ppts estimated faster mph with more extreme verbs

  Supports the idea of leading questions influencing answers
• (+) A03: Gabbert


  Participants watch videos of crime in different witness points

  • Found 71% of information recalled was information not from their viewpoint, after pair discussion

  Supporting the idea of post event discussion influencing answers
• (+) A03: Johnson + Scott

  Study with 2 conditions:

  1. Normal conversation occuring, man entering the room with greasy hands and a pencil
  2. Hostile conversation, glass breaking, man entering the room with bloody hands and a knife

  • Finding 49% could identify the man with the pencil, but only 33% could identify the man with the knife

  Supports the idea of weapon focus in anxiety
• (-) A03: Yuille + Cutshall


  Found that 4 months after a deadly shooting, 13 witnesses resisted misleading information, and that those with most stress (closest to shooting) had best recall
• (-) A03: Lab Experiments

  Lab Experiments can have demand characteristics, participants may figure out the aims, creating a response bias and have no emotional impact on them, lowering validity of the studies