Welsh police deployed facial recognition tech with a 92% false positive rate, but they're sure it's fine


The South Wales Police deployed a facial recognition technology at the June 2017 Champions League soccer final in Cardiff, and 92% of the people identified by the system as matches for suspiciousness were false positives.

The 92% figure became known after Wired UK and The Guardian used public records requests to get statistics on the usage of facial recognition at the event; they discovered that the system generated 2,470 alerts, 2,297 of which were faulty.

The South Wales Police say they arrested "over 450" people at the event thanks to facial recognition technology, but none were the result of false positives. They assure the public that the technology is therefore fit for purpose.


"Of course, no facial recognition system is 100 percent accurate under all conditions. Technical issues are normal to all face recognition systems, which means false positives will continue to be a common problem for the foreseeable future," the police wrote. "However, since we introduced the facial recognition technology, no individual has been arrested where a false positive alert has led to an intervention and no members of the public have complained."

The agency added that it is "very cognizant of concerns about privacy, and we have built in checks and balances into our methodology to make sure our approach is justified and balanced."


2,000 positive matches reached with our ‘Identify’ facial recognition technology in past 9 months with over 450 arrests. [South Wales Police]


UK police say 92% false positive facial recognition is no big deal [Cyrus Farivar/Ars Technica]


(Image: Steindy, CC-BY-SA)