factors affecting EWT: misleading information

• eyewitness testimony


  the abilty of people to remember the details of events such as accidents and crimes.

  accuarcy of EWT can be effected by factors such as misleading information and anxiety.
• two types of misleading information

  1. leading questions
  2. post-event discussion
• misleading information


  incorrect information given to an eyewitness usually after the event
• leading questions

  • when you are asked a question, the wording may lead or mislead you to give a certain answer
  • eg. police may 'direct' a witness to give a particular answer
• research on leading questions

  Loftus and Palmer (1974)
• research into leading questions- aims

  aim- to see how leading questions affect EWT
• research on leading questions- findings

  findings- the mean estimated speed was calculated for each group. For; contacted- 31.8mph estimated speed, hit- 34.0mph, bumped- 38.1mph, collided- 39.3mph, smashed- 40.5 estimated speed.
• research on leading questions- conclusions


  conclusion- the leading question biased the eyewitness's recall of the event
• research on leading questions- method

  method- Loftus and Palmer(1974) had 45 particpants (students) watch a film clip of car accidents and then asked them questions about the accident. They were asked to describe how fast the cars were travelling and were given the critical (a leading question or also known as misleading question) question: "how fast were the cars going when they hit each other?". There were 5 groups of particpants and each group were given a different verb in the critical question. The verbs were; hit, contacted, bumped, collided and smashed.
• (Why LQs affect EWT) Response bias explanation


  Suggests the wording of the question has no real effect on the participant's memories, but just influences how they decide to answer. When a participant gets a leading question using the word smashed, this encourages them to choose a higher speed estimate.
• post-event discussion


  witnesses will discuss what they have seen

  occurs when there is more than one witness to an event

  may influence accuarcy of each witness's recall of the event
• why leading questions affect EWT

  Loftus and Palmer (1974) conducted a second experiment that supported the substitution explanation, which proposes that the wording of a leading questioh changes the participant's memory of the film clip. This was shown because participants who originally heard smashed were later more likely to report seeing broken glass (there was none) than those who heard hit. The critical verb altered their memory of the incident.
• Gabbert et al (2003)- method

  • studies p's in pairs - matched pairs
  • each p watched a video of the same crime, but from differnt points of view
  • they then discussed what they saw
  • they then individually completed a recall test on what they had seen
• Gabbert et al (2003)- findings

  • 71% of the p's mistakenly recalled aspects they did not see in the video themselves but had picled up from the discussion
  • control group with no discussion--> 0% mistakes of recall
  • evidence of memory conformity
• memory conformity


  witnesses go along with each other for social approval or because they believe the other witnesses are right and they are wrong

  unlike memory contamination, their memory is not changed
• memory contamination


  explaination why PED affects EWT

  when witnesses to a crime discuss it with each other, their EWT's may become altered or distorted.

  this is because they combine information/misinformation from other witnesses, with their own memories
• A03- real world aplication

  • strength- reserach onto misleading information has important practical uses in criminal justice system
  • the consequences of EWT can be very serious (loftus&Palmer- belived leading q's can have a distorting affect on memories)
  • police must be careful about how they phrase q's when interveiwing
  • psychologists are sometimes asked to act as expert witnesses in court and explain limits of EWT to juries
  • shows psychologists can help improve the way legal system works, especially by protecting innocent people from faulty convictions from unreliable EWT
• A03- counter to real world aplication

  • practical apllications of EWT mat be affected by issues with the research
  • eg. Loftus &palmer conducted study in a lab- different from witnessing a real crime- less stressful
  • other research- foster et al- stated that what eyewitnesses remember has important consequences in the real world, but participants responses in reasearch do not matter in the same way- so research p's are less motivated to be accurate
  • siggest that researchers are too pessimistic about the effects of misleading information- EWT may be more dependable than studies suggest
• A03- evidence challenging memory conformity- limitation of memeory conformity explaination

  • researcher showed their p's clip. 2 versions- eg. robbers hair dark brown in one but light brown in the other. P's discussed clips in pairs each having seen different versions. Often didnt report what was seen in the clips/from the other witnesses, but a 'mix' of the two. eg. a common answer to what colour the robbers hair was- 'not dark or light brown but medium'. Suggests thst the memory itself is distorted thriugh contamination by misleading PED rather than memory conformity
• A03- demand charcateristics in EWT

  • lab study- controlled variables- reserschers argue that many answers given by ps in lab studies are due to demand characteristics
  • p's usually want to show social desirabilty and not let the researcher down so they guess when asked a question they don't know the answer to