There is a city that has scanned the faces of more than 3 million people on the street and it is not in China, but in Europe

A few days ago a man was walking down the street when, without realizing it, a camera scanned his face. As he continued walking, a sophisticated system compared his face to a police database, sent the alert, and within minutes he was arrested. It happened in London.

The city of cameras. London is one of the most surveilled cities in the world; according to some sourcesin its streets there are more than 600,000 cameras controlling everything that happens. For some years now, in addition, they have a real-time facial recognition system to identify dangerous criminals, and it seems that the system is being as effective as it is controversial.

In numbers. London’s Metropolitan Police say that since the beginning of 2024 they have made 2,500 arrests, of which 2,100 are related to violent and sexual crimes against women and girls. The system scanned more than 3 million faces in one year and only generated ten false positives. During a pilot in the Croydon district at least 470,000 passers-by were scanned with only one false positive. According to the police, the result of this test was a 10.5% crime reduction.

How it works. The facial recognition cameras they have installed are capable of scanning up to 5,000 faces per hour. What they do is send the data to a police operations room where an AI system, signed by the Japanese company NEC, is dedicated to compare them with the police databasewhere there are more than 17,000 registered suspects. When there is a match, an alert is issued to officers in the area so they can make the arrest.

Opposition. Organizations like Big Brother Watch has carried out campaigns against this systemarguing that it risks normalizing mass surveillance in public spaces and calling the technology ‘Orwellian’. Furthermore, they strongly question its true operational profitability since, while the police boast of making an arrest every 35 minutes, they warn that these statistics hide the enormous number of hours of the agents and the immense logistical resources that the system requires on the streets, diverting efforts from traditional and more proportionate police work.

The debate has intensified after the unprecedented use of the system in a political protest in London. Big Brother Watch took the case to the High Court, but it ruled in favor of the legality of the technology, paving the way for its expansion.

In favor. Despite opposition from some organizations, according to Police Director Lindsey Chiswick, the technology is “revolutionary” and completely secure, stressing that the biometric data of those who do not match the list of suspects are immediately destroyed. There are also fears that the algorithm discriminates based on race, but the police hide behind the fact that the tests carried out concluded that the system is accurate and does not present ethnic or gender biases. According to Chiswick, citizen support is around 80% in surveys.

Image | Levi Meir ClancyUnsplash

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