Based on that dismal performance, and perhaps emboldened by the coming Brexit and its liberation from EU privacy rules, the Met have announced that they are rolling out permanent, citywide facial recognition. The system will use "bespoke" watchlists whose criteria are not disclosed, though they will include people "wanted for serious and violent offences."

The cameras will be placed in popular tourist and shopping spots.

When the camera flags an individual, police officers will approach and ask them to verify their identity. If they’re on the watch list, they’ll be arrested. “This is a system which simply gives police officers a ‘prompt’, suggesting ‘that person over there may be the person you’re looking for,’” said the Metropolitan police in a press release.

Operational use of the cameras will only last for five or six hours at a time, says BBC News, but the Met makes clear that the use of this technology is to be the new normal in London.

London police to deploy facial recognition cameras across the city [James Vincent/The Verge]

(Image: Cryteria, CC-BY, modified)