By Rowland Manthorpe, technology correspondent
Facial recognition in China is "absolutely correct" and "spot on", the head of the Metropolitan Police Federation has said, calling for it to be deployed in London "on a 24-hour basis".
Ken Marsh, who is chairman of the Metropolitan Police staff association, said he believed the "fantastic" technology could be used to catch criminals and terrorists.
Mr Marsh gave the example of the 2017 London Bridge attack, when police lost track of the terrorists in the aftermath of the killings.
He said: "Facial recognition, if it was pointed in certain areas in London on a 24-hour basis, could pick these individuals up… if we could have stopped that I'm all for this."
The Chinese government has invested heavily in facial recognition, deploying it in the country's massive network of CCTV cameras.
China's use of facial recognition has been widely condemned, after the technology was reportedly used to track and control members of the largely Muslim Uighur minority group, up to one million of whom are believed to be held in detention camps.
Human Rights Watch described the system as "China's algorithms of repression".
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"Although China is a very intrusive country and I don't agree with a lot of what they do," Mr Marsh told BBC Radio Essex's breakfast show, "[on facial recognition] they've got it absolutely correct. They're recognising individuals… they've got it spot on".
In response, David Davis MP said Mr Marsh had "swallowed Chinese propaganda".
He told Sky News: "Mr Marsh needs to check his facts before he tries to write policy. Independent analysis showed facial recognition was wrong four out of five times.
"He has simply swallowed Chinese propaganda about their own repressive practices.
"They may not care about false positives. In this country we do. We call it miscarriage of justice, and we do all in our power to avoid it."
The Metropolitan Police has been conducting public tests of live facial recognition, which scans every face in a crowd to pick out wanted individuals, since August 2016.
On Wednesday, Sky News reported that 81% of "suspects" flagged by the Met's facial recognition technology were identified incorrectly, according to the first independent review of the controversial programme.
Asked about the figures, Mr Marsh said: "That's just absurd. I've not heard that from anyone."
If the technology was that inaccurate, then, he said: "Logic would tell you it's just not fit for purpose. We'd throw it in the bin if it that's bad."
The Metropolitan Police maintains its technology only makes a mistake in one in 1,000 cases – but it uses a different measurement to arrive at this conclusion.
Rather than comparing the number of successful matches to the number of people flagged by the system, it compares successful and unsuccessful matches to the total number of faces captured by the camera.
"I do accept there are areas we need to get correct," Mr Marsh said. "But I would add to that, if we stop someone incorrectly and they've done absolutely nothing wrong and we explain to them, 'I'm so sorry, we've got this one wrong' – if you've done nothing wrong, I personally wouldn't have any problem with it whatsoever."
Mr Marsh continued: "I do not condone what the Chinese do with the technology, but they have faRead More – Source