Eyewitness Testimony

Page 1

Misleading Information

AO1

Loftus and Palmer investigated how misleading information could distort eyewitness testimony accounts.

Procedure:

Forty-five American students formed an opportunity sample. This was a laboratory experiment (with an independent measures experimental design) with five conditions, only one of which was experienced by each participant.

Participants were shown slides of a car accident involving a number of cars and asked to describe what happened as if they were eyewitnesses. They were then asked specific questions, including the question "About how fast were the cars going when they (hit/smashed/collided/bumped/contacted) each other?". They word chosen was the condition.

Findings:

The estimated speed was affected by the verb used. The verb implied information about the speed, which systematically affected the participants' memory of the accident.

Participants who were asked the "smashed" condition thought the cars were going faster than those who were asked the "hit" condition. The participants in the "smashed" condition reported the highest speeds, followed by "collided", "bumped", "hit" and "contacted" in descending order.

AO3

The research lacks mundane realism, as the video clip does not have the same emotional impact as witnessing a real-life accident and so the research lacks ecological validity.

A further problem with the study was the use of students as participants. Students are not representative of the general population in a number of ways. Importantly they my have less experienced drivers and therefore less confident in their ability to estimate speeds. This may have influenced them to be more swayed by the verb in the question.

A strength of the study is that it's easy to replicate. This is because the method was a laboratory experiment which followed a standardised procedure.

Page 2

Anxiety

AO1

When we are in a state of anxiety, we tend to focus on whatever is making us feel anxious or fearful, and we exclude other information about the situation. If a weapon is used to threaten a victim, their attention is likely to focus on it. Consequently, their recall of other information - such as the appearance of the attacker - is likely to be poor.

Clifford and Scott (1978) found that people who saw a film of a violent attack remember fewer of the 40 items of information about the event than a control group who saw a less stressful version. As witnessing a real crime is probably more stressful than taking part in an experiment, memory accuracy may well be even more affected in real-life.

However, a study by Yuille and Cutshall (1986) contradicts the importance of stress in influencing eyewitness memory. 21 witnesses observed a shooting incident in Canada outside a gun shop which one person was killed and a second seriously wounded. The incident took place on a major thoroughfare in mid-afternoon. All of the witnesses were interviewed by the investigating police, and 13 witnesses (aged 15-32 years old) agreed to a research interview 4-5 months after the event. The witnesses were also asked to rate how stressed they had felt at the time of the incident, using a 7 point scale. The eyewitness accounts provided in both the police and research interviews were analysed and compared.

The results of the study showed the witnesses were highly accurate in their accounts, and there was little change in amount or accuracy of recall after 5 months. The study also showed that stress levels did not have an effect on memory, contrary to lab findings. All participants showed showed high levels of accuracy, indicating that stress had little effect on accuracy. However, very high anxiety was linked to better accuracy. Participants who reported the highest levels of stress were most accurate (about 88% accurate compared to 75% for the less-stressed group).

AO3

One strength of this study is that it had high ecological validity compared with lab studies which tend to control variables and use students populations as research participants.

One weakness of this study was that there was an extraneous variable. The witnesses who experienced the highest levels of stress were actually closer to the event (the shooting) and this may have help with the accuracy of memory recall, as well as making stress levels higher and so showing an apparent relationship between stress and accuracy.