factors effecting eye witness testimony

• loftus and palmer 1974 - interaction between language and memory


  • seeing effects of leading questions upon estimates of speed questions
  • watched video of a car crash and were asked questions about the speed using different word like hit / smashed
  • those that were asked smashed had an 9mph higher difference than those asked contacted (41 v 32)
  • 45 students
  • labatory experiment
  • independent measures
  • IV - verb used
  • DV - ps estimate of the speed
• loftus and palmer 1974 - part 2, broken glass questions


  • same experiment as previous
  • came back 1 week later
  • yes or no questions asked about glass
  • those who answered the 'smashed question' said yes to the glass question
  • showing questions can alter peoples memories
  • 150 students
  • labatory experiment
  • independent measures
  • IV - verb used in the question
  • DV - yes/no answer to the broken glass
• gabbert 2003 - post event discussion


  • studied Ps in pairs
  • each watched video of same crime but from different points of view
  • some could see others couldnt eg. title of the book
  • Ps discussed together before completing individual recall tests
  • 71% of Ps mistakenly recalled aspects they didnt see but picked up in discussion
  • in control group there was no discussion and the corresponding figure was 0%
  • evidence of memory conformity
• memory contamination


  genuine confusion
• memory conformity


  going along with someone else
• + real life applications

  • hugely important practical uses in the real world where consequences of EWT can be serious
  • police need to be careful when questioning witnesses as leading questions can have a distorting effect
  • psychologists belive they can make improvements like improving the way the legal system works and by appearing in court trials as expert witnesses
• ~ the tasks are artificial


  • Ps watched film clips in a lab - less stressful so the experiment is artificial as the consequences dont matter as opposed to a real eye witness testimony
  • there evidence to suggest emotions may have an influence on memory
  • but may be too negative - EWT may be more dependable than many studies suggest
• ~ evidence challenging memory conformity

  • it is post event discussion that alters EWT rather than a desire to win social approval / saying the other person is right
  • skagerburg and wright 2008 - showed Ps clips of a mugging and hair colour of mugger was different. Ps discussed with eachother each having seen a different clip and they reported a 'blend' of the 2 -common answer was that mugger had medium brown hair rather than light or dark
  • this shows they arent just blindly following the other person as there is a blend
• demand characteristics 


  going along with what you think youre supposed to do
• ~ demand characteristics

  • zaragoza and mccloskey argue many answers given by Ps in lab studies are due to demand characteristics
  • they think that theyndo not want to let the researcher down, so they guess when they are asked a question they dont know the answer to
• seema clifasefi et al 2013


  • attempted to use leading questions to implant false memory
  • gave Ps document that claimed to be personalised profile put together by a computer software based on responses to a questionaire
  • for one group the profiles included false info that they under 16 drank so much alcohol they were sick
  • later Ps did a memory test - leading question asked when they had become sick from drinking too much, and found a significant number of Ps 'recalled' being sick from drinking too much before they were 16 and now disliked certain drinks because of this non existent experience
• context reinstatement (CR) - cognitive interview 


  mentally recreating the environment from the original incident. aim is same as RE, eg. weather, mood, purpose
• report everything (RE) - cognitive interview 


  include every detail of the event even if it seems irrelevant, aims to trigger useful information
• changing perspective (CP) - cognitive interview 


  recalling event from multiple perspectives. eg. imagining POV from other witnesses. aim is to trigger useful info
• reverse order (RO) - cognitive interview 


  reversing order in which events occured. aims to vary route through memory in order to increase recall - checking for truth
• CI varies with age

  • below 6 - struggle due to complex nature of some of the questions
  • the elderly (wright and holiday) - the older the P, the less complete and accurate the result, but when using CI, they recalled significantly greater detail without giving false info
• CI is said to produce an increase of correct info

  • kohnken - meta analysis of 55 studies, average 41% increase in amount of correct info generated with CI, helpful when info is stored but not accessible -triggers
  • milne and bull - 2 elements were very useful, RE and CR, but most of the sample were university students
• real world issues with CI experienced by the police

  • training / costs / time - takes more time than available, demands placed in the interviewer to 'probe' effectively, quality and quantity of CI training is an issue
  • due to these issues police only favour RE and CR