The first independent evaluation of the Metropolitan police’s use of face recognition warned it is “highly possible" the system would be ruled unlawful if challenged in court.

The news: London’s police force has conducted 10 trials of face recognition since 2016, using Japanese company NEC’s Neoface technology. It commissioned academics from the University of Essex to independently assess the scheme, and they concluded that the system is 81% inaccurate (in other words, the vast majority of people it flags for the police are not on a wanted list). They found that of 42 matches, only eight were confirmed to be correct, Sky News reports.

Police pushback: The Met police insists its technology makes an error in only one in 1,000 instances, but it hasn’t shared its methodology for arriving at that statistic.

Rising fears: As face recognition becomes more ubiquitous, there’s growing concern about the gender and racial bias embedded into many systems. With that (and other concerns) in mind, San Francisco banned its use by public agencies last month. That doesn’t do anything to stop it from proliferating in the private sector, but at least it might mean it can’t be wielded by authorities with the power to arrest you.

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