ewt: misleading information

• leading questions

  • respone-bias explanation - working of a question has no enduring effect on a eyewitness's memory of an event, but influences the kind of answer given
  • substitution explanation - working of a question does affect eyewitness memory; it interferes with its original memory, distorting its accuracy
• key study 1: Loftus + Palmer (1974) Leading questions


  procedure: 45 pp's watched film clips of car accidents + then answered questions about speed. critical question: 'About how fast were the cars going when they hit each other?'. Five groups of pp's, each given a different verb in the critical question: hit, contracted, bumped, collided or smashed
• key study 1: Loftus + Palmer (1974) Leading questions


  findings: the verb 'contacted' produced a mean estimate speed of 31.8 mph. for the verb 'smashed', the mean was 40.5 mph. the leading question (verb) biased eyewitness recall of an event. the verb 'smashed' suggested a faster speed of the car than 'contacted'
• post-event discussion (PED)

  • memory contamination : when co-witnesses discuss a crime, they mix (mis)information from other witnesses with their own memories
  • memory conformity : witnesses go along with each other to win social approval or because they believe the other witnesses are right
• key study 2: Gabbert et al (2003) post-event discussion


  procedure: paired pp's watched a video of the same crime, but filmed so each pp could see elements in the event that the other couldn't. both pp's discussed what they had seen on the video before individually completing a test of recall
• key study 2: Gabbert et al (2003) post-event discussion


  findings: 71% of the pp's mistakenly recalled aspects of the event that they didn't see in the video but had picked up in the post-event discussion. in a control group, where there was no discussion, there was no errors
• strength- real life applications

  the research has led to the important practical uses for police officers because the consequences of inaccurate ewt can be serious. Loftus (1975) claimed that leading questions can have such a distorting influence on memory that police officers need to be careful in how they word the question when interviewing eyewitnesses. research into ewt: is one area where psychologists can make an important difference to the lives of real people
• limitation of Loftus + Palmer's study - used artificial materials

  pp's watched film clips of an accident, a very different experience of witnessing a real accident, its less stressful, Yuille + Catshell (1986) found that witnesses of a traumatic real armed robbery had very accurate recall after four months. this shows that using artificial tasks tells us little about how leading questions affect ewt in real crimes or accidents
• limitation: individual differences


  Anastasia + Rhodes (2006) found that older people were less accurate than younger people when giving eyewitness reports. however, they also found that all age groups were more accurate when identifying people of their own age group. research studies often use younger people as the target to identify. so some age groups may seem less accurate but this is not really the case