Eye witness testimony

• Definition of Eye witness testimony

  • is the evidence provided by people who witnessed a particular event on crime - relies on recall from memory
  • includes eg. descriptions of criminals eg. hair colour height etc.
  • witnesses are often inaccaure in their recollection of events + the people involved - has important implications when it comes to police interviews.
• What effects Eye witness testimony ?

  -Can be affected by misleading information

  -Loftus and Palmer investigated how EWT can be distorted - leading questiona where a certain answer is implied to the question.

  -For example - how much will prices go up next year ? = leading question befause your implying prices will go up
• Loftus and Palmer (1974) - EWT EXP

  EXP-1- participants were shown a film of a multiple car crash - asked a series of questions including how fast do you think the cars were going when they hit ? in different conditions, the word hit was replaced with smashed collided bumped or contacted.

  -Results - participants given the word smashed estimated highest speed - 41mph those given the word contracted gave the largest estimate 32mph.
• Loftus and Palmer exp EWT EXP2

  -Split into 3 groups one group given the word smashed other hit and the 3led control group wasn’t given any indication of vehicles speed - week later they were asked did you see any broken glass ? but participants were more likely to say they did see it.

  -Conc- leading questions can affect accuracy of people’s memories of an event.

  -Eval - has implications for questions in police interviews - was artificial watching a vid isn’t as emotional arousing as real life, demand characteristics - exp design gave a clue =reduced validity and reliability.
• How did Loftus and Zani investigate - alteration wording of question ?

  -Altering wording of a question can produce a leading question that =distort EWT.

  -Participants shown a film of a car crash was asked did you see the broken glass? or did you see the broken headlight ?

  -results 17% to die who were asked the glass claimed they saw one compared to 7% in the group asked headlight.

  Conculsion -simple use of the wording the is enough to affect the accuracy of people’s memories of an event.
• Evaluation of Loftus and Zani - leading question wording

  -Has implications for EWT - was a lab study - made it possible to control extraneous variables

  -Means it possible to establish cause + effect - but artificial they were shown a film not an actual car crash - lacked ecological validity
• What can affect the accuracy of recall after an event?

  Post event discussion
• What was the main finding of Shaw et al's study regarding participant recall accuracy?

  Recall accuracy varied based on who answered first
• In Shaw et al's study, what was the recall accuracy when a participant answered first?

  58% accurate
• What was the recall accuracy for participants when the confederate answered first and was accurate?

  67% accurate
• How did the accuracy of recall change when the confederate provided incorrect answers?

  Correct recall fell to 42%
• What was the focus of Gabbert's study regarding participant recall?

  Effects of misleading information on recall
• What were the two methods through which participants in Gabbert's study were exposed to misleading information?

  Conversation or reading a written report
• What was the outcome for both groups in Gabbert's study regarding reporting inaccurate information?

  Both groups reported more inaccuracies with a confederate
• How did the method of receiving misleading information affect recall accuracy in Gabbert's study?

  Participants were more likely to report inaccuracies with a confederate
• How can anxiety affect focus ?

  • Psychologists believe that small increases in anxiety and arousal may increase the accuracy of memory but high levels have a negative effect on accuracy.
  • In violent crimes where anxiety and arousal are likely to be high the witness may focus on central details eg. weapons and neglect other details eg. what the criminal is wearing.
• Loftus - Weapon focus on EWT

  M - Independent groups design , participants heard a discussion in a nearby room . In one condition a man came out of the room with a pen and grease in his hands. In the second condition the man came out carrying a knife covered in blood . Participants were aksed to identify the man from 50 photos.

  R- in condition 1 49%accuarte. only 33% in condition 2 were correct.

  con- when anxious and aroused witnesses focus on a weapon at the expense of other details.

  • eval high eco validity participants weren't aware that it was staged. but ethical issues- stress = knife.
• Cognitive interview definition + is it effective ?

  • Cognitive interview technique helps with memory retrieval + communication techniques - helps to improve recall in police interviews.
  • Geiselman found that this procedure produced more accurate detailed memories than the SPI technique suggesting that this technique is effective.
• Cognitive interview components 


  • Change of narrative order - recall event in different chronological orders - eg. from beginning to end.
  • Change of perspective - recall event from different peoples perspectives eg. from the offenders pov.
  • Mental reinstatement of context - recall both the enviornmental and emotional context of the event eg. weather and personal feelings.
  • Report everything - recall all info even those that have little relevance or which is remembered less confidently or is incomplete.