Paul Hyland almost never forgets a face. He's a "super recognizer," and that's giving an unusual kind of help to his employer: Scotland Yard.
Several years ago, for example, London police were on the lookout for a burglar wanted for nine robberies. About a month after seeing the burglar's picture, Hyland and two colleagues were stuck in traffic.
"I looked up and noticed this guy coming out of a university and knew it was him," Hyland recalled, adding that neither of his colleagues recognized the burglar. Hyland arrested the suspect, who confessed after questioning.
"If I've met someone before and see them again, I'll usually know where I know them from, even if I can't remember their name," he said.
How does Hyland do it? Nobody knows. But since 2011, about 200 London police officers have been recruited to an elite squad of super recognizers. Officials say they have tripled the number of criminal suspects identified from surveillance photos or on the street each week, and even helped prevent some crimes like muggings, drug deals and assaults.
"When we have an image of an unidentified criminal, I know exactly who to ask instead of sending it out to everyone and getting a bunch of false leads," said Mick Neville, Detective Chief Inspector at Scotland Yard. Neville started the super recognizer unit after realizing the police had no system for identifying criminals based on images, unlike those for DNA and fingerprints.
The unit proved especially valuable after riots hit London in the summer of 2011. After the violence, Scotland Yard combed through hundreds of hours of surveillance video. So far, there have been nearly 5,000 arrests; around 4,000 of those were based on police identifications of suspects from video images. The super recognizers were responsible for nearly 30 percent of the identifications, including one officer who identified almost 300 people. A facial recognition software program made only one successful identification, according to Neville.
Weeks before the Notting Hill Carnival, the biggest street festival in Europe, kicked off last month, the super recognizers were given images of known criminals and gang members. After the carnival began, 17 super recognizers holed up in a control room to study surveillance footage and spot the potential troublemakers.
Once targeted people were identified, police officers were sent to the scene as a pre-emptive strategy. Neville said that likely prevented some crimes like thefts and assaults.
Neville said one super recognizer saw what he thought was a drug deal, but wasn't sure. The next day, the super recognizer saw the same person and when police intervened, they found the suspect with crack cocaine.
He noted that the officers aren't infallible and that their identification is only the start of a case, after which police start looking for other evidence.
Legal authorities warned it could be problematic to use super recognizers as expert witnesses in court, such as in situations where they identify criminals based on an imperfect image.
"Unless we subject them to (rigorous testing), then we are just taking their word on trust and we have no reason to do this," said Mike Redmayne, a law professor at the London School of Economics. "Perhaps they can do what they say, but we don't have the evidence yet," he wrote in an email. "If it was up to me, I would not (allow) it in court."
In the U.S., experts thought it would be up to individual judges to decide whether super recognizers needed to be verified before allowing their testimony in court.
"It's not clear to me that the law will demand they be tested first," said David Kaye, a distinguished professor of law at Penn State. He said the identification skills of super recognizers might be analogous to those of sniffer dogs, whose ability to sniff out drugs are mostly accepted without confirmatory tests. Kaye also noted cases where expert witnesses didn't need to have their skills verified before testifying in court and thought that in most instances, the prosecution would have more evidence than simply the identification of an alleged criminal by a super recognizer.
He said the skills of super recognizers might be more plausibly used in obtaining search warrants.
"There aren't strict rules for getting a warrant," Kaye said. "The judge is supposed to exercise independent judgment but often anything goes," he said, explaining that a super recognizer's identification of a suspect based on a grainy image might be sufficient to issue a search warrant.
Charles Farrier, a spokesman for the U.K. privacy group, No CCTV, called the police's use of super recognizers "the latest gimmick" being used to promote the widespread use of surveillance cameras. According to the group, Britain has the most surveillance cameras per person in the world.
"It is a slippery slope when we want to start to justify the widespread use of blanket surveillance 'just in case' a policeman spots someone," he wrote in an email. "The use of (super recognizers) will lead to cases of mistaken identity but more than that, it forms part of a ubiquitous surveillance culture that spreads fear and distrust," he said.
But Brad Duchaine of Dartmouth College in Hanover, N.H., a psychologist who has published on super recognizers, said he thinks the London police approach makes sense. "People are much better at facial recognition than software (is), so using people is a very reasonable thing to do," Duchaine said.
Interpol, the International Criminal Police Organization, said they weren't aware of any police forces worldwide using super recognizers or similar techniques to the London Metropolitan Police.
The abilities of some London super recognizers impressed a skeptical psychologist, who now plans to study them further.
"When I was told that the police have these amazing people who recognize everyone, I was a bit dubious," said Josh Davis of the University of Greenwich in England. At Scotland Yard's request, Davis ran several tests on 18 of the best-performing super recognizer cops and found many scored off the charts when compared to average people. He's now planning to examine all 200 super recognizers on the London police and to develop a test for new recruits to see who might have special facial recognition abilities.
"Unfortunately, we don't know how (the super recognizers are) doing it," he said. Maybe they process facial features more quickly and holistically than other people, he said. Davis said other police departments in Britain have asked him to test their officers to see if they're super recognizers but none have a specialist team just yet.
While most people can learn to remember faces better, scientists say, it is unlikely they could match the powers of a super recognizer.
"I think some of this is hard-wired," said Ashok Jansari, a psychologist at the University of East London.
It's like the natural advantage that sprinting champion Usain Bolt holds, he said. "Bolt has a very particular physical make-up that makes him the fastest runner in the world," he said. "You could teach other people to use the same techniques he's using, but they will never be as fast."
Hyland's Olympic-class memory for faces is an aberration in his own life.
"I'm quite forgetful with basic things," the 30-year-old said. "I'll walk into a room and forget what I was coming in for, or I'll drive to the shops and get a load of stuff except for what I was supposed to get.... Like everyone else, I'm not so good with a shopping list."
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