Facewatch are keen to say that they’re not a technology company themselves – they’re a data management company. They provide management of the watch lists in what they say is compliance with the European General Data Protection Regulation (GDPR). If someone is seen shoplifting on camera or by a staff member, their image can be stored as an SOI; if they are then seen in that shop again, the shop manager will get an alert. GDPR allows these watch lists to be shared in a “proportionate” way; so if you’re caught on camera like this once, it can be shared with other local Facewatch users. In London, says Fisher, that would be an eight-mile radius. If you’re seen stealing repeatedly in many different cities, it could proportionately be shared nationwide; if you’re never seen stealing again, your face is taken off the database after two years.

Carlo is not reassured: she says that it involves placing a lot of trust in retail companies and their security staff to use this technology fairly. “We’re not talking about police but security staff who aren’t held to the same professional standards. They get stuff wrong all the time. What if they have an altercation [with a customer] or a grievance?” The SOI database system, she says, subverts our justice system. “How do you know if you’re on the watch list? You’re not guilty of anything, in the legal sense. If there’s proof that you’ve committed a crime, you need to go through the criminal justice system; otherwise we’re in a system of private policing. We’re entering the sphere of pre-crime.”

Fisher and Facewatch, though, argue that it is not so unlike the age-old practice of shops and bars having pictures up in the staff room of regular troublemakers. The difference, they say, is that it is not relying on untrained humans to spot those troublemakers, but a much more accurate system.

The problem is that, at the moment, there is very little regulation – other than GDPR – governing what you can and can’t do with a facial-recognition system. Facewatch say, loudly and often, that they want regulation, so they know what they are legally allowed to do. On the other hand, Carlo and Big Brother Watch, along with other civil liberties groups, want an urgent moratorium and a detailed democratic debate about the extent to which we are happy with technologies like these in our lives. “Our politicians don’t seem to be aware that we’re living through a seismic technological revolution,” she says. “Jumping straight to legislation and ‘safeguards’ is to short-circuit what needs to be a much bigger exercise.”

Either way, it needs to happen fast. In Buckinghamshire, Paul Wilks is already using the technology in his Budgens, and is finding it makes life easier. When he started, his shop would have things stolen every day or two, but since he introduced the system, it’s become less common. “There’s definitely been a reduction in unknown losses, and a reduction in disruptive incidents,” he says. As well as a financial gain, his staff feel safer, especially late at night, “which is good for team morale”. If enough retailers start using facial-recognition technology before the government takes notice, then we may find that the democratic discussion has been short-circuited already.

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