Police have had no response to the E-FIT
"If the witness tells you the suspect has green hair, then you just have to go with it," says psychologist Dr Jim Turner of the Open University, an expert in facial perception.
E-fits are produced by an operator working under the direction of a witness. Police have to follow strict guidelines and can only respond in a way which is led by the witness, says Dr Chris Solomon, managing director of VisionMetric Ltd, which produces the E-FIT software used by 90% of police forces in the UK.
Both parties are also required to sign a witness statement to the effect that the operator has not "led" the witness towards a particular likeness. It means the quality of the images cannot be altered by the operator without direction from the witness.
They are often working from memory and sometimes in a distressed state. They also might not have seen the suspect's face for very long or be unable to recall a lot of detail. In the case of the lettuce e-fit, the victim was 85 years old.
'Hostage to ridicule'
"For these reasons, results with e-fits can vary widely," says Dr Solomon. Ultimately, they can only be as good as the witness.
The courts have long recognised the fallibility of onlookers' testimony. In 1976, the Devlin Committee's investigation of identification evidence found that many witnesses overstated their ability to single out the right person.
A recent study involving the Open University, the BBC and Greater Manchester Police (GMP) tested the memories of 10 volunteers by mocking-up "crimes". It found the difference between what people though they'd witnessed and what had actually happened was "staggering".
These are not the only potential problems. Witnesses and the acquaintances of the suspects whom police want to reach will be looking for very different things in an e-fit, says Dr Turner.
"When you don't know someone - as will be the case with most witnesses who end up doing an e-fit - you tend to focus on their external features, such as their hair or the shape of their face," he says.
"But when you do know someone, it's their internal features you notice, that's why you can still recognise someone when they get their hair cut. So there's a disconnect that you have to get over."
Of course e-fit has been designed to mitigate against this. When creating an image, the operator will ask the witness to recall everything they can about the suspect.
Great value
The computer programme will generate a face that may not initially resemble the suspect, but as the shapes, sizes and positions of each feature are altered the picture will - hopefully - offer a more accurate representation.
However, there are still more potential pitfalls. Professor Peter Hancock of Stirling University, who has been involved in the development of evoFIT, an alternative identification programme, believes use of colour is a distraction - and, in the "lettuce head" case, a hostage to ridicule.
Rapist Ross Gleave was caught with the help of EvoFIT
"If you get the hair right, for instance, it doesn't make a lot of difference," he says. "But if you get it wrong, it just looks stupid - as this case shows. That's why evoFIT is in black and white."
With this system, users repeatedly select complete faces from screens of alternatives to allow a composite to "evolve". The approach has the potential to allow construction when a witness has seen the face, but cannot describe it in detail.
What all those involved in the area agree is the relationship between the operator and the witness has to be right for the technique to work.
Bruce Burn, 56, worked as an artist for Northumbria Police in the days before e-fit, but says the principles for coaxing a good image out of a witness are the same.
"The biggest danger is that they defer to you because you're the artist or the police officer," he says. "You need to ensure that they can be hard on you and say 'no, that's rubbish' - otherwise it's not their recollection that you're capturing."
Research suggests that such composites only have an accuracy rate of about 20%. But when you have nothing else to go on they can be good odds.
"Composites images are often used when the police have no other means to attempt to identify a suspect," says Dr Solomon. "As such they perform a very important function and one often not well understood by the public."
I think the lettuce hair has worked wonders, a lot more people would have seen this picture! Something to ridicule or clever ploy? I guess we'll have to wait and see.
I was kidnapped, robbed and raped when I was in my mid 30s. I was given the option by the police, of either doing an e-fit profile immediately after the crime, or waiting until the next day. I chose to both give the statement and give the suspects description to the e-fit expert, within an hour of the event. My reasoning was that I wanted to pass on the information, that I was holding, as soon as possible, then I would be able to "let go" of the incident and start to heal. I later found from working in police training, that this timing is often easier for crime victims, as shock often protects the brain from trauma overload for a few hours. This shock may protect and insulate the victim emotionally. (We did gain a conviction and my E-Fit was incredibly close to the later arrest "mug shot".)
I had to provide an e-fit of a man who attacked me the day before my 16th birthday. On my 16th birthday I spent two hours with a police officer constructing an efit. I can say from experience that it is extremely difficult to do. Many people who have been assaulted would prefer to block out the face of the person who did it. What would have helped in my case is if the people who had witnessed the attack had come forward to help me at the time. I did the best I could with my efit but still didn't feel happy with it at the end. By the time you have looked at hundreds of different noses you can't trust your own memory any more.
A lot of people who have to give descriptions or work with an operator to build an E-Fit, will have a very hard time Consciously remembering the face of the criminal. Just like when you see a face in a dream, but cant remember the exact details when you awake. If you were to ask the average person to create an E-fit of their own face, without use of a mirror, they wouldn't be able to provide an exact image.
If I recall correctly, there was an efit type of picture of the yorkshire ripper, which was very accurate.
There's been a lot of rubbishing of "lettuce head" and comments that make out the witnesses must be either suffering from dementia or just plain stupid. The detractors all seem to ignore the fact that some people DO HAVE green hair. Hair dyes have existed for quite a long time and this suspect just might have used one.
In normal circumstances , trying to describe a face feature could be hard but if you have been indirectly involved in an incident and harmed in any way , to remember a person's features after extreme stress is nigh on impossible to most people. The examples that were used in this article is a prime example of how hard it would be for the Police to determine a criminal's guilt.
Elizabeth Loftus et al is a woman who did a study about photofits, it is very difficult to remember a persons face especially is there is a weapon involved. People will instantly focus on the weapon and adrenaline will take hold, it is very difficult to remember a persons face after an incident like this. Another study, done by Bruce et al discovered that people do not remember faces by the "internal" features i.e the eyes, nose, mouth etc. They mainly remember the external features such as hair, face shape and ears. Police when doing photofits focus on the internal features rather than external which makes sense, considering there are many people with similar hair, but it isn't so easy to remember those things. It has to be said though, some photofits are very accurate and some are down right atrocious.
A lot of people who have to give descriptions or work with an operator to build an E-Fit, will have a very hard time Consciously remembering the face of the criminal. Just like when you see a face in a dream, but cant remember the exact details when you awake. If you were to ask the average person to create an E-fit of their own face, without use of a mirror, they wouldn't be able to provide an exact image.
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