London’s Metropolitan Police force — the UK’s largest — deployed its Live Facial Recognition (LFR) technology in Oxford Circus, a very busy area of the city. The system scanned 8,600 faces, and, as Business Insider reports, spit out eight matches — only one of which was a person wanted by the police. That’s a false-identification rate of 86 percent.

Business Insider quoted a spokesperson for the Met Police defending the practice. “LFR deployments are accompanied by clear signage alerting members of the public to the fact that LFR is in operation,” they said. “We want the public to know that we are there and want to provide reassurance that we are working to make London safer.”

London’s police announced the measure would go into widespread use in January. The idea is that cameras will be placed in populous areas to scan for targets on designated watch lists — individuals, the Met Police say, that are wanted for “serious and violent offenses.”

Obviously, civil liberties groups in London have pushed back against the cameras. Big Brother Watch, a UK-based nonprofit, had some harsh words about the Met Police’s latest trial. “This blows apart the Met’s defense that facial recognition surveillance is in any way proportionate or that the staggering inaccuracy is mitigated by human checks,” they told BI. “This is a disaster for human rights, a breach of our most basic liberties and an embarrassment for our capital city.”