Factors affecting the accuracy of eyewitness testimony: misleading information, including leading questions and post-event discussion

The Effects of Misleading Information on the Accuracy of EWT

Description, AO1 Research into the Accuracy of EWT – Leading Questions: Loftus and Palmer (1974)

Elizabeth Loftus’ and EWT – The role of misleading information Elizabeth Loftus (1975) argues that memory is reconstructive in nature. She suggests that an individual’s evidence, in terms of eyewitness accounts, are in fact extremely unreliable pieces of evidence, as memory of an event is influenced by the form of questioning they receive after the event. This is known as the post-event effect and has been demonstrated in much research.


This study aimed to investigate the accuracy of memory after witnessing a car accident. In particular, it was to see if leading questions distort the accuracy of an eye-witnesses immediate recall.


  • Laboratory study
  • 45 of Loftus’ own students were divided into 5 group and shown 7 films of different road traffic accidents.
  • After each film the participants were given a questionnaire which asked them to describe the accident and then asked a series of specific questions about it.
  • There was one critical question. This question was “About how fast were the cars going when they hit each other?”
  • One group of participants were given this “hit” question; the other 4 groups were given the verbs smashed, contacted, bumped , collided in place of the word “hit”


Loftus and Palmers Results


The experiment shows that misleading information (in the form of leading questions) can affect memory recall of eyewitnesses. The leading questions create post-event information, this information starts to form part of the individual’s original memory, this memory then reconstructs – the individual believes that the post-event information is in fact the original memory and falsely report this during testimony questioning.

Evaluation, AO3 of Loftus and Palmer’s (1974) research into the accuracy of EWT:


(1) Point: Further research by Loftus and Palmer supports the role of misleading information affecting the accuracy of EWT. Evidence: They showed 150 students a video of a car crash and 50 were asked the critical question with the word ‘smashed’, 50 with the word ‘hit’ and 50 were the control group (a group for comparison) and not asked anything at all. After a week they students were asked if they saw any broken glass (there wasn’t any), participants in the ‘smashed’ condition were 2x as likely to recall the false memory of broken glass. Evaluation: This is a strength because it demonstrated that misleading information, in the form of post-event information, can affect the accuracy of EWT.

(2) Point: Loftus & Palmer’s research has high internal validity. Evidence: For example, Loftus and Palmer were able to control the videos that the participants watched, the verbs that they were given in the questions, the filler questions that were used to prevent demand characteristics.  Evaluation: This is a strength because it means that the research has measured what it intended to, the effect of misleading information on EWT accuracy, which gives credibility to the research and to the theory of the post-event effect.



(1) Point: Laboratory experiments such as those carried out by Loftus may not represent real-life. Evidence: Foster et al (1994) found that if participants thought they were watching a real-life robbery, and also thought that their responses would influence the trial, their identification of a robber was more accurate. Evaluation: This is a weakness because it can be argued that the findings from artificial laboratory research settings such (as Loftus’ study) may not be applicable to real life EWT behaviour, which weakens the research as support for the role of misleading information affecting the accuracy of EWT.