If the system detects a match, it sends an alert, and two trained team members manually review it to decide whether it is a match and what response is appropriate.
Next steps may include observing the person, contacting the police, or intervening to ask them to leave the store.
The system is calibrated to only send an alert when it detects a match with an accuracy level of at least 92.5%.
No images of people under the age of 18 or vulnerable people are entered into the watchlist.
Foodstuffs said only images that are matched with a person on the watchlist are stored.
All other images that do not match will be instantly deleted.
It’s not the first time Foodstuffs has introduced facial recognition.
Between March and September 2024 Foodstuffs North Island trialled facial recognition across 25 of its New World and Pak’nSave stores.
The Office of the Privacy Commissioner’s public inquiry into the trial found it had met privacy standards.
Facial recognition continued to be used in 25 North Island supermarkets, with other retailers now following suit.
General manager of retail Tim Donaldson said Foodstuffs South Island had chosen to trial the technology after stores had been repeatedly targeted “with serious, threatening behaviour” – even after people were trespassed.
“This trial will help us understand if facial recognition can help our teams identify repeat offenders so we can act quickly to prevent them causing more harm,” Donaldson said.
Foodstuffs South Island said it had engaged with the Office of the Privacy Commissioner and completed a Privacy Impact Assessment.
“We recognise some people may have questions about the use of FR,” Donaldson said.
“That’s why we’ve published clear information on our website about how the system works and the safeguards we’ve put in place, and are happy to answer any questions about how [facial recognition] will be used in our trial.”
At the end of the three-month trial results will be carefully reviewed.