Researchers develop better criminal composites
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Charlie Frowd, a psychology professor at the University of Central Lancashire in England, has developed a new criminal composite sketch system called EvoFIT. An example of one of the computerized faces is on the monitor.
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When Brian Coates meets with police officers to tell them about a new computerized system he is using to produce images of criminal suspects, he'll start with some questions.
"I'll say, 'How many of you have partners?' " the detective constable said in an October interview in Driffield, England, "and most of them will hold up their hands."
Then he'll pick out one officer and say, "tell me about your partner's ears."
"He'll say, 'What?' "
"Describe her ears to me, I'll say. Do they have long lobes or short ones?"
" 'I don't know,' he'll say."
"Well what about her nose?"
" 'Well, it's normal,' he'll say."
"But what about the shape of the nostrils?"
" 'Well, I don't know,' he'll say, and by this time, of course, they're all laughing."
"Finally I'll say, 'Well if I held up a picture of her, would you know her?' And of course he'll say yes."
This little party game is Mr. Coates' way of making a point: We don't recognize faces -- even the ones of people we live with -- by being able to recall their eyes, noses, ears or eyebrows.
Instead, we see and know their faces as a whole. And that's the approach embodied in the computerized composite system Mr. Coates is field testing in the Humberside region on the east coast of England.
Known as EvoFIT, it has been developed over the past several years by a team at the University of Central Lancashire in western England, led by psychology professor Charlie Frowd.
EvoFIT tries to mimic the brain's face recognition system by showing witnesses a series of face images that have been morphed by the computer, and then asking them to select the ones that most closely match their recollection.
That's a sharp departure from older computerized systems like E-FIT, which asked witnesses to select individual noses, eyes, ears and other features and place them on a facial template.
In early tests, both E-FIT and EvoFIT showed about a 20 percent success rate of someone being able to identify a person from a composite, but those were lab tests that allowed the artists to create images immediately after a witness had seen a face.
When witnesses waited two days between seeing a photo and helping prepare a composite, though, the E-FIT method dropped to 5 percent identification rates, Dr. Frowd said.
First Published December 27, 2010 12:00 am
