5 - Factors affecting accuracy of Eyewitness Testimony

misleading information, including leading questions and post-event discussion; anxiety.

Eyewitness Testimony (AO1)

goes through 3 stages

• encoding details into the LTM - may be partial as the event occurs quickly, at night and/or includes complex actions

• retaining information for some time - can be lost or modified during retention, or other activities can interfere with the memory

• retrieval of information from LTM - retrieval cues may or may not be present, which can affect the accuracy of the memory

Leading Questions

substitution explanation -

Leading Questions (AO1) (1)

Loftus and Palmer (1974)

• split 45 participants into 5 groups and showed them 7 different clips of traffic accidents, then subsequently asked about those accidents

• in the ‘critical question’ participants were asked how fast the cars were going when they contacted/hit/bumped/collided/smashed each other

• each of the 5 groups were asked the same question with a different verb

• contacted group reported an average speed of 31.8 mph

• hit group reported an average speed of 34 mph

• bumped group reported an average speed of 38.1 mph

• collided group reported an average speed of 39.3 mph

• smashed group reported an average speed of 40.5 mph

this suggests that the effect of leading questions can negatively contribute to the accuracy of EWT, as a more ‘harsh’ verb was given a faster crash speed

Leading Questions (AO1) (2)

Loftus and Palmer (1974)

• wanted to investigate the substitution explanation

• tested a new set of 150 participants and split them into groups of 3

• they were shown a minute-long clip of a car accident, and asked questions about speed

• they were then asked to return a week later, and were asked 10 questions including if they saw broken glass

• 6/50 in the control group reported seeing broken glass

• 7/10 in the ‘hit’ group reported seeing broken glass

• 16/50 in the ‘smashed’ group reported seeing broken glass

even though there was no broken glass, those with the ‘harsh’ verb were more likely to report seeing broken glass

this suggests that the effect of leading questions can negatively contribute to the accuracy of EWT

Leading Questions (AO3)

Leading Questions (AO3) - real world effects

A criticism of the leading questions is that the participants all watched film clips of car accident, which is different to watching a real accident

Yuille and Cutshall (1986)

• found that witnesses to an armed robbery gave accurate reports of a crime 4 months after the event, despite having the influence of leading questions

suggests that real-world accidents are not susceptible to the effects of leading questions

perhaps the perceived consequences of getting it wrong in real life could mean that participants might be more motivated to be accurate as opposed to laboratory studies where there is little at stake.

lessens the usefulness of Loftus and Palmer’s research in understanding EWT in the real world

Post-event discussion

• witnesses discuss what they saw regarding the event, leading to contamination of memory

• demonstration of the conformity effect where witnesses copy other people’s accounts to win social approval

Post-event discussion (AO1)

Gabbert (2003)

• used matched pairs design to show each partner the same event but from different points of view, meaning each partner saw slightly different things

• both participants then discussed what they saw, before completing a test of recall

• 71% of participants went on to mistakenly recall items acquired during the discussion

• the control group had a 0% rate of mistaken recall

this suggests that post-event discussion can negatively contribute to the accuracy of EWT

Post-event discussion (AO3) - effect reduction

Bodner et al. (2009)

• some participants were told that anything they hear from co-witnesses is second-hand information and they should instead only recall their own memory

• these participants generally had more accurate recall than participants that weren’t told

suggests that the effects of post-event discussion can be reduced if people are made aware of the fact

Misleading Information (AO3) - real-world impact

A strength of research into misleading information is that it proves the negative effect of it, and thus has real-world application in the criminal justice system ehich relies heavy on EWT for investigating crimes

Wells and Olson (2003)

• states that mistaken EWT is the single largest factor in wrongful convictions.

• this led to DNA being used more to help exonerate those who have been wrongfully convicted

this research has been used to warn the justice system of problems with EWT, and has led to the presence of psychologists as expert witnesses in court trials

Anxiety (AO1)

weapon focus

• presence of a weapon can cause anxiety, causing a witness to focus on it instead of other events

Loftus and Burns (1982)

• participants shown a violent crime where a boy is shot in the face

• participants had significantly impaired recall for the events running up to the violent incident

suggests anxiety has a negative effect on EWT

Christianson and Hubinette (1993)

• questioned 58 real victims of a bank robbery

• found that those who had actually been threatened were more accurate with recall, compared to other witnesses

• continued to be true 15 months later

suggests anxiety has a positive effect on EWT

Anxiety (AO3) - the element of surprise

A limitation of Johnson and Scott’s research is that it could have been testing the element of surprise as a reason for reduced recall. The participants could have been surprised by the paper knife with blood on it.

Pickel (1998)

• conducted an experiment where scissors, a handgun, a wallet or raw chicken was used as handheld items in a hairdressing salon video

• the scissors condition was the control as it would be the regular tool used to cut hair

• found that eyewitness accuracy was lower in the high unusualness conditions (raw chicken and handgun)

suggests that unusualness could have attracted attention to the object, distracting from the rest of the surroundings

lessens the usefulness of Johnson and Scott’s research as it could have been testing surprise instead of the idea of weapon focus. Maybe weapon focus is only one part of the element of surprise as a whole

Anxiety (AO3)

A strength of anxiety as an explanation for reduced reliability of EWT is there is research backing

Johnson and Scott (1976)

• participants sat in a waiting room where one of two situations were witnessed

• one group heard a discussion in the next room, and saw a man leave with a men and grease on his hands

• the other group heard an argument in the next room