Eye witness testimony

Eye witness testimony

1. Leading Question

   • (Loftus study) Pps were shown a film of car accident and then asked either 'How fast was the white sports car going when it passed the stop sign?' or How fast was the white sports car going when it passed the barn while travelling along the country road?' The result was that 17% who had been exposed to the false information reported seeing a barn. This shows that non-existent item had been inserted into the witnesses' memories for the film suggesting that participants had indeed been influenced by the wording of the question
   • A question which, because of the way it is phrased, suggests a certain answer
   • (Loftus and Palmer study)Pps were shown a film clips of traffic accidents and were then asked to estimate the speed of the vehicles involved in each crashes. Different words eg. smashed, collided, bumped etc. were used in the questions to see whether the wording would affect recall. The result was that the more violent the word was, the higher the speed pps would estimate. This suggests that wording of questions to eyewitness can affect their judgements and be a crucial factor in prompting false memories.
     • Evaluation: Students were used as pps which cause issue to generalise findings as adults may have a better estimation because they have more experience. Lack of ecological validity because accident tends to happen unexpectedly. Demand characteristics.

2. Post-event discussion

   • (Wright study) Two groups of pps were shown a series of story pictures about a women stealing a man's wallet. In one condition, the woman had an accomplice and another had not. Both groups gave an accurate recall at this stage. Pps were then paired up, one person from each condition, and to discuss the detail of event. The result was that 79% of the pps agreed that there had been accomplice in the story, even they had both seen different versions. This shows that eye witness can be influenced by others
   • Conversations with other eyewitnesses can start to distort memory

3. Anxiety

   • (Yuille and Cutshall study) Following a real crime, 13 witnesses were asked to interview with psychologists. The participants were asked two misleading questions. Despite the recall was done after four months, the memory was not affected. There did not appear to be any relationship between levels of stress reported at the time of the crime and accuracy of recall. This shows that level of stress is not related to accuracy of recall and misleading questions do not necessarily produce inaccurate recall of events.
     • Evaluation: High ecological validity as it was carried out in a real-life situation. It may be suggest that witness with higher stress level were closer the the event and therefore had a better view, so a better recall is produced.
   • At very low levels of arousal eyewitness testimony is poor as it is at very high levels of arousal. This is supported by Yerkes-Dodson Law

4. General Evaluation: Crucial information recalled by the eyewitness is not affected by misleading information. Less crucial details are more often recalled inaccurately than key facts.Cognitive interview to improve the accuracy of recall.

5. Weapon focus

   • (Loftus and Loftus study) Pps were shown a series of slides depicting an incident in a fast-food restaurant. Half the pps saw a customer point a gun at the cashier and the other half saw him hand the cashier a cheque. Some of the pps' eye movement were recorded and their memories were assessed. The result was that pps have focused on the gun for longer period than on the cheque.
     • Evaluation: The study relies on slides rather than real people which cannot generalise the study to realistic setting. This cannot show cause and effect.
   • (Loftus study) Pps were left in a room . Pps were put in two situations. One was about a man leaving the lab holding a pen with grease on his hands and the other one was about a man emerging from the lab carrying a paper knife covered in blood. They were then asked to identify the man who had left the lab. The results was that pps in the pen condition recall better than those in the paperknife condition. This shows that fear and anxiety causes the witness to concentrate on the weapon and therefore distracts attention away.
     • Evaluation: Ethical issue of deception. Artificial task. Demand characteristics. Other research( Chirstianson and Hubinette) have shown that witness have good memories for stressful events that occur in real life
   • Where eyewitnesses look at the weapon rather than anything else. This means that their recall of other information can be poor

6. Cognitive interveiw

   • 1.To recreate the context of the original incident (not revisiting the scene) 2. To report every detail 3. To recall the event in different orders 4. To change perspectives
   • (Geiselman research) 89 students were shown a video of violent crimes and they were interviewed individually after 48 hours. The results were that by using a cognitive interview there was a significant higher number of corrected items being recalled. (41.15) More corrected items could be recalled in CL although error rates was a bit higher
   • General Evaluation: The cognitive interview takes up a long time which means memory may experience interference or fade out. The cognitive interview has the potential to enhance eyewitness memory although must be wary of confabulation