Accuracy of EWT - Misleading Information

Eyewitness Testimony

the ability of people to remember the details of events such as accidents & crimes that they have seen

Misleading Information

Supplying information that may lead a witness’ memory for a crime to be altered.

Leading Questions

A question that, either by its form or content, suggests to the witness what answer is desired or leads him or her to the desired answer

Loftus & Palmer (1974) Experiment 1

• 45 students shown 7 diff. films traffic accidents

• After each film, participants were given a questionnaire which asked them to describe the accident & then answer a series of specific Qs about it

• 1 group asked the critical Q, other 4 groups given verbs in place of the word ‘hit’

What was the critical Q in experiment 1

• A leading Q

• ‘About how fast were the cars going when they hit each other?”

What verbs replaced ‘hit’ ?

Smashed, collided, bumped, contacted

Mean speed estimates for verbs

• Smashed = 40.8

• Collided = 39.3

• Bumped = 38.1

• Hit = 34.0

• Contacted = 31.8

Loftus and Palmer: Experiment 2

• New set of participants were divided into 3 groups & shown a film of a car accident lasting 1 min

• Asked Qs about speed

• Participants asked to return 1 week later - were asked a series of 10 Qs

• Another critical Q also asked

Critical Q for Experiment 2

• Leading Q

• ‘Did you see any broken glass?’

Findings for experiment 2

Findings: Shows leading Q did change the actual memory a participant had for the event

Post event discussion (Gabbert et al (2001))

A conversation between co-witnesses or an interviewer & an eye witness after a crime has taken place may contaminate a witness’s memory of the event

Conformity Effect (Gabbert et al, 2003)

• Participants watched the same video of a crime from diff POVs

• When allowed to discuss the video, 71% recalled aspects of crime they didn’t see in video

  • They go along w. each other to win social approval or cos they believe the other witnesses are right

• Control group had no discussion, = 0% incorrect recall

Repeat Interviewing (LaRooy et al, 2005)

• Each time an eyewitness is interviewed, there is the possibility comments from the interviewer will become incorporated into their recollection of events

• Interviewer may use leading Qs & thus alter individual’s memories of events

  • Especially the case when children are being interviewed about a case

Strength 1: (Real word app.)

Point: 1 strength of research into misleading info is that it has important practical uses on the criminal justice system

Evidence: Consequences of inaccurate EWT can be v. serious such as it leading to false accusations & lifelong sentences ( is shown in many cases by the innocence project)

Explain: Loftus (1975) believes leading Qs can have such distorting effects on memory that police officers need to be v. careful about how they phrase their Qs when interviewing eyewitnesses

Link: This shows that psychologists can help to improve the way the legal system works, especially by protecting innocent people from fault convictions based on unreliable EWT.

Limitation 1: (EWT in real life)

Point: However, the practical applications of EWT may be affected by issues w. research

Evidence: For example, Loftus & Palmer’s participants watched film clips in a lab, a very different experience from witnessing a real world event & so they don’t take the experiment seriously. They may also not be emotionally aroused in the way they would in reality

Explain: Also, Foster et al (1994), pointed out what witnesses remember has important consequences in the real world, but participants responses in research don’t matter in the same way ( so research participants are less motivated to be accurate)

Link: This suggests that research such as Loftus are too pessimistic about the effects of misleading info. EWT may be more dependable than many studies suggest

Limitation 2: (Response Bias)

Point: Another weakness of research into EWT is the possibility of a response bias

Evidence: E.g. Loftus & Palmer found that leading Qs changed the orig. memory. However, Belcerion & Bowers (1983) replicated a study by Loftus et al (1978) & found that participants aren’t susceptible to misleading info if Qs are presented in the same order as the orig. data

Explain: This means that the order of Qs had a significant effect on the answers given about the incidents, & therefore, memory change was due to response bias not storage

Link: Therefore, this provides an alternative explanation to Loftus & Palmer & highlights the importance of question order in police interviews