A Sainsbury's customer was wrongly identified as a shoplifter by an AI-powered camera system and asked to leave the store. The incident happened on August 6 at the supermarket's East Dulwich branch in London.
Matt Arnold, 46, was shopping for supplies ahead of a comedy event at a nearby venue. He was waiting at a self-service till for a staff member to approve an alcohol purchase.
Instead of getting help with his purchase, two members of management approached him. They told him he could not be served because of an incident earlier that week.
Arnold said he had already scanned all his items and used his Nectar loyalty card. He pointed out that this behavior does not match a typical shoplifter.
What Happened at the Store
Arnold was escorted out of the store. As he left, he said he saw a CCTV monitor showing a red circle around his face.
Sainsbury's head office contacted Arnold the next day to apologize. The company said the mistake was caused by human error rather than a fault with the AI software itself.
This is not the first case involving Sainsbury's facial recognition system, which is supplied by a company called Facewatch. Last September, another customer was wrongly flagged at a different London branch. Facewatch later confirmed that customer was not even in its database.
Facewatch has also been linked to similar misidentification cases at other retailers, including a discount store in 2024 and another shop in Wales last year.
Arnold said he believes staff are struggling to use the system correctly during busy periods. He said mistakes are likely to happen when workers are not properly trained to handle the alerts.
Company Response and Accuracy Claims
Sainsbury's confirmed the technology has been paused at the East Dulwich store while it investigates. The company said it still supports using the system at other locations.
A spokesperson said the Facewatch system has a 99.98% accuracy rate and that a trained manager reviews every match before action is taken.
Facewatch said a correct alert was sent in this case, but staff made an error when handling it in the store. The company said pausing a store after an incident is a standard precaution while employees receive more training.
Sainsbury's pointed to industry data showing daily incidents of violence and abuse against shop workers have risen sharply since 2019. The retailer said early trials of the technology led to a drop in theft and anti-social behavior at two stores, with most offenders not returning.
Big Brother Watch director Silkie Carlo said mistakes are unavoidable when a large retailer runs facial checks at this scale. She called on Sainsbury's to remove the technology entirely.
Arnold donated a £150 goodwill voucher from Sainsbury's to a local food bank. He questioned why the system is still running in other stores if the company recognizes it caused a problem in this one.
Sainsbury's has not announced a timeline for when the investigation at the East Dulwich store will conclude.
