The new 'jigsaw' method seeks to modify the existing system used by most police forces by reducing to a minimum the memory interference that distorts a witness's vision of a suspect. Under the current E-FIT system, as a witness gives a description of, say, the eyes, the computer chooses the best set of eyes for you, and so on. The witness does not see the face until it is completed. What we are saying is that you can improve things by allowing witnesses to watch the face build up. However, as it is important that the features are always seen as part of a face, a cartoon outline and features are used to replace those elements that have yet to be described.
People distort things, even forget things.
Psychologists have been working with the police for quite a while to try and improve those memory processes. Changing the way police conduct interviews to elicit information for the E-FITs aims to get the best information possible out of the witness. In addition, Dr Kemp and his team are investigating the benefits of using the evidence of multiple witnesses to create a more accurate image of a suspect's face. But the police have been interested for some time in what the effect would be of having multiple witnesses. It could be that seeing four E-FITs would confuse people.