Outline and evaluate the different levels of accuracy of different types of witness

Eyewitness testimony (EWT) refers to an account given by people of an event they have witnessed; it is an important area of research in cognitive psychology and human memory. Juries tend to pay close attention to EWT and generally find it a reliable source of information. However, research into this area has found that EWT can be affected by many psychological factors: anxiety, age, reconstructive memory and consequences.

Anxiety is almost always associated with real life crime. Deffenbacher (1989) theorized the ‘Inverted U-theory’ stating that low levels of anxiety cause cognitive performance (memory) to also be relatively low. As the anxiety increases, so does the cognitive performance until optimum level. Any further anxiety produces a rapid drop in the performance. Therefore, it can be predicted that stressful incidents leads to witnesses having inaccurate recall due to their high anxiety levels. Research support for this theory and its relevance EWT can be found in a field experiment carried out by Peters (1988).
Loftus (1979) aimed to see whether anxiety in EWT affected later identification. An experimental and control group were tested upon in which the control group overheard a low-key discussion in a lab about an equipment failure. A person then emerged from the laboratory holding a pen in grease covered hands. Next, the experimental group overheard a heated and hostile debate between people in the lab. After the sound of breaking glass and crashing chairs, a man walked out of the room holding a knife with blood covered hands. Participants were then asked to recall the mans’ appearance form 50 photos; 49% from the controlled group recalled correctly however only 33% recalled correctly from the experimental group. This experiment demonstrated the ‘weapon focus