Sainsbury's Store Pauses Facial Recognition After False Shoplifting Claim (theguardian.com)
- Reference: 0185034264
- News link: https://yro.slashdot.org/story/26/08/18/0742229/sainsburys-store-pauses-facial-recognition-after-false-shoplifting-claim
- Source link: https://www.theguardian.com/technology/2026/aug/17/humiliated-sainsburys-store-pauses-ai-scanning-after-false-shoplifting-accusation
> Sainsbury's has [2]paused the use of AI face scanning in one of its stores after a customer was wrongly identified as a shoplifter and ejected from the shop. "I was embarrassed, mortified even, and felt quite humiliated and powerless," Matt Arnold, 46, said of his ordeal. The comedy promoter was buying supplies in the store in East Dulwich, in south-east London, for a standup event at Dulwich Hamlet football club when, after scanning his items and a Nectar card, he was approached by two managers who told him he could not be served owing to an earlier incident. He was then asked to leave and they tried to escort him from the store.
>
> As he left, he saw an overhead CCTV monitor alert with a red circle surrounding his face. He asked the shop staff to keep his shopping in the trolley so his friend could come and pick up the supplies for the comedy night happening soon next door. "I think they were quite confused by this, understandably, but agreed and my colleague Dave went in to pay for and pick up the shop about five minutes later. There was no pause for thought from the staff, no suggestion that they understood this is not how a shoplifter would behave. Just blindly following the machine's orders." Sainsbury's head office apologised to Arnold the next day and has paused use of its AI-assisted Facewatch technology in the store while an investigation takes place.
Arnold says the facial recognition tech should be paused in all stores. "Anyone could be falsely accused and at some point that will be someone vulnerable, someone with mental health issues like anxiety. It's inevitable," said Arnold. "Also, I would worry about the confidence-destroying effect of it happening to a younger person or someone less willing or able to stand up for themselves as I have done."
A Sainsbury's spokesperson said: "We have contacted Mr Arnold to apologise for his experience at our Dulwich superstore. The incident was caused by human error, not the facial recognition technology. Customers can be reassured that the Facewatch system has a 99.98% accuracy rate, and every match is reviewed by a trained manager." A Facewatch spokesperson said their technology was not at fault in this case. "A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store," they said.
[1] https://slashdot.org/~Bruce66423
[2] https://www.theguardian.com/technology/2026/aug/17/humiliated-sainsburys-store-pauses-ai-scanning-after-false-shoplifting-accusation
99.98% (Score:5, Interesting)
> the Facewatch system has a 99.98% accuracy rate,
So one in every five thousand people who walk into your stores is going to be falsely accused of a crime? Wow, thanks for making abundantly clear that people should NOT shop there...
Re: (Score:2)
It's penalising the customers only.
Re: (Score:1)
> It's penalising the customers only.
It's penalizing the significant part of society that desperately wants to embrace a high-trust society.
Fuck all the goddamn racists who racist-think otherwise.
Re: (Score:3, Interesting)
It really means nothing. What does the 99.98% "accuracy" even refer to? For all we know, it could be the true negative rate (e.g. it correctly detects who is NOT a shoplifter 99.98% of the time).
At minimum, you need a "confusion matrix", you need False Positive, True Positive, False Negative, True Negative, to have a minimum of information to evaluate any prediction system.
Re: (Score:1)
These systems are banned in Germany for this very reason.
Re: (Score:2)
It's laboratory tests in perfect condition with a tailor made data set designed to make the number look better. In other words it's a lie. It's not even lying with statistics it's just a lie.
Re: 99.98% (Score:1)
A short course in Bayes' theorem should be mandatory for anyone making that kind of "success rate" claim.
Re: (Score:2)
Ah, the priors strike again! There should be a mandate that every accuracy claim to comes with the expected positive predictive value and the number of expected false positives.
Re: (Score:3)
>> the Facewatch system has a 99.98% accuracy rate,
> So one in every five thousand people who walk into your stores is going to be falsely accused of a crime? Wow, thanks for making abundantly clear that people should NOT shop there...
More interesting is if 1 in five thousand is also a shoplifter, that means 1 fals positve and one real one, so a 50/50 chance of being wrong when an identificattion is made.
Re: (Score:3)
and
> "A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store,"
So was the guy a shoplifter or not? Because apparently not and the human error was acting on the alert it seems. Sounds like the front fell off.
Re: (Score:1)
> So was the guy a shoplifter or not?
Something not yet mentioned is that face recognition can't even tell whether someone "is a shoplifter" NOW. At best, it can only identify that someone is on a list. A list of what? People who have been convicted of shoplifting? Or accused? Or just a list of people the shop-keeper doesn't like? Like the infamous terrorist watch list or license-plate readers, who's on the list, how do people get onto the list, how do they get off the list, who makes the list, and how many people are on the list incorrectly?
Re: (Score:2)
> and
>> "A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store,"
> So was the guy a shoplifter or not? Because apparently not and the human error was acting on the alert it seems. Sounds like the front fell off.
Facial recognition software doesn't actually "recognize" your face, it selects a series of points the algorithm thinks important in a pattern and matches them to other patterns in the database. It's the same technology, though less advanced, than fingerprint readers. Until better filters for the patterns were developed there were a lot of false positives in the fingerprint readers as well, and I suspect this will be the case with facial recognition software as well.
Re: (Score:1)
> the Facewatch system has a 99.98% accuracy rate,
> So one in every five thousand people who walk into your stores is going to be falsely accused of a crime? Wow, thanks for making abundantly clear that people should NOT shop there...
> Flag as Inappropriate
My math may be wrong but that would be 2 out of every thousand nt five thousand.
Re: (Score:3)
Your math, is, alas, wrong. 99% is one in one hundred. 99.9% is one in one thousand. 99.99% is one in ten thousand. 99.98% is two in ten thousand or one in five thousand, as the OP stated.
Re: (Score:3)
Even if we discount various other confounding factors, and assume in good faith that the 99.98% "accuracy" is somehow meaningful on individual recognition basis one should consider this:
Sainsbury's stores serve millions of customers per week. As per usual, they do not seem to be publishing any current customer amounts themselves, but [1]https://rspo.org/members/3-001... [rspo.org] claims "Over 16 million customers visit 740 Sainsbury's stores each week", and that was nearly 20 years ago.
Assuming that figure has any truth
[1] https://rspo.org/members/3-0010-06-000-00/
Re: (Score:2)
I bet management can't do the math. They only read the 99.98% accuracy promise on the supplier powerpoint and drooled themselves.
Re: (Score:2)
That's why the people selected by the software are **supposed** to be checked against the image in the database. Apparently in this case they didn't bother with that step.
Re: (Score:2)
It's potentially a big GDPR issue as well. If they shared the face data with anyone else (these shops usually share the data) then they need to tell him who and compensate him for now having to get all of the others to fix the mistake too.
Otherwise the next time he walks into some other shop using the same data, he will get accosted again.
Re: (Score:2)
Yeah, I get mail at my address for some guy that owned a BMW. Mostly mail about his SiriusXM subscripton. So I started terminating his SiriusXM subscription, forcing him to turn it back on, and... I no longer receive his mail. My point is, we all get mail addressed to other people, so the databases tracking people's addresses are full of bad data. Somebody apparently keeps applying for credit using the address I lived at 15 years ago. Thankfully, they keep getting denied despite my perfect credit score.
Re: (Score:2)
That's not good. We regularly get collection notices for someone who not only doesn't live at our address but has NEVER lived at this address.
Re: 99.98% (Score:2)
Plus some of us have been confused with other people with the same name. My full name, all three names, is the 400th most common name in the US and with just first and last it's about number 103. When I try to ID with services which think they know things about me they ask if I've lived on streets I've never lived on, I tell them no and they tell me I'm not me...
Re: (Score:2)
Please please please be Johnny J. Johnson.
Re: (Score:3)
It's also an outright lie. Ignoring the fact that facial recognition has a hard time with black and brown faces the figure cited is based on laboratory tests in perfect conditions.
Once again I am so tired of being lied to and in such an obvious fashion.
Re: 99.98% (Score:2)
I imagine my software that simply returns "not a shop lifter" would have a similar accuracy rate.
The Path to Dystopia is, De-humanize Humanity (Score:2)
Incidents of AI [machines][computers] reigning superior over Humans is on-the-rise and out-of-control. Every power-of-authority is eager to use technology like Flock cameras and facial recognition, as a club to de-humanize Humanity. As pointed-out in countless books and movies, when the foundation of civilized society is stripped-away, no civilized society remains.
Re: (Score:3)
> Incidents of AI [machines][computers] reigning superior over Humans is on-the-rise and out-of-control. Every power-of-authority is eager to use technology like Flock cameras and facial recognition, as a club to de-humanize Humanity. As pointed-out in countless books and movies, when the foundation of civilized society is stripped-away, no civilized society remains.
We lost the clanker war one little step at a time. From "remember my password" features in browsers to carrying our little life-controllers under the label "organizer" in our pockets to letting the machines dictate behavior for us. These types of stories are just one more example of how we've already given up, and consider the machines superior. It's also why I've been so frustrated over the last decade and some change by every self-driving story being filled with comments from people convinced the machines
Investigation... (Score:2)
"Sainsbury's head office apologised to Arnold the next day and has paused use of its AI-assisted Facewatch technology in the store while an investigation takes place."
What investigation? It has a 0.02% failure rate, which is very, very high. End of investigation. Discard the tech.
"The incident was caused by human error, not the facial recognition technology. Customers can be reassured that the Facewatch system has a 99.98% accuracy rate, and every match is reviewed by a trained manager."
Every match
Re: (Score:2)
I'm sure that technically they said something like "The man may be a shoplifter", and thus were correct in that sense. But using a system that does that at that error rate is NOT reasonable. This is like the automated driving systems that require a human driver to take over within 2 seconds. NOT a good idea.
Re: (Score:3)
Notice how they blamed a human and defended the machine. Sounds like the facial recognition company drafted the response.
This is a major part of what is killing "AI" (Score:5, Insightful)
The dumb sonofabitch WOULD NOT back down.
His system had obviously accused the wrong man, but the machine "doesn't make mistakes".
The current state of "AI" is primitive and terrible.
They lie, they cheat, they take the easy way out, even if it's wrong.
People are going to be killed by shitty, fake "AI".
Do this to me, and I'll sue. (Score:2)
Do this to me, and I'll sue. I don't care for what -- the usual bullshit of "emotional damage" and "mental anguish" and all that.
I encourage every person erroneously flagged to do so. The only thing that hurts corporations is a hit on the wallet -- so hit their wallet, hard, and often.
Re: Do this to me, and I'll sue. (Score:2)
I will destroy your store on the way out. Every single shelf will be emptied onto the floor. Every display toppled.
Re: (Score:2)
Like the "lefties" who stormed the capital on January 6?
Re: (Score:2)
That's a destructive crime, not a violent crime. "Violence" is when you target other people. "Destruction" for property. In this case, destruction with provocation.
Still not a very clever way to react, of course.
Re: Do this to me, and I'll sue. (Score:2)
It's not destruction. It's vandalism. A misdemeanor for which they cannot place you under citizens arrest. It just leads to hours of wages paid to reorganize the store.
Re: Do this to me, and I'll sue. (Score:2)
Weird, in my US state (CA) I can do a citizen's arrest if I witness a misdemeanor
Re: Do this to me, and I'll sue. (Score:2)
You need to look up what a violent crime is.
Re: Do this to me, and I'll sue. (Score:2)
You must be a bootlicker who always does what he's told by his betters.
Re: (Score:2)
That would make you a criminal.
Re: (Score:2)
> Do this to me, and I'll sue. I don't care for what -- the usual bullshit of "emotional damage" and "mental anguish" and all that.
This is the second-highest level of self-unawareness demonstrated on Slashdot after all the maggots claiming Democrats rape kids.
You'll sue, you don't know for what, but emotional damage and mental anguish are bullshit? You absolute clown.
Re: (Score:2)
You must have lawyers in your family.
Reassured (Score:2)
> Customers can be reassured that the Facewatch system has a 99.98% accuracy rate,
I'm sure Matt Arnold is extremely reassured.
First and foremost... (Score:2)
Retailers and shop managers ARE NOT law enforcement. If they SUSPECT someone is a criminal, they should notify the police with the appropriate EVIDENCE.
Re: (Score:2)
I think they do have some shopkeeper privileges to detain but they rest on having reasonable grounds (ie. they saw you slip something into your pocket)
Asking this guy to leave I presume must have been on other grounds though, pehaps some fine print you walk past as you enter the store saying they reserve the right to refuse service to anyone for any reason.
Re: (Score:2)
In UK, if I'm correct, law allows shopkeepers from refusing service only for security reasons.
[1]https://www.milnerslaw.co.uk/c... [milnerslaw.co.uk]
Still, I believe the appropriate thing to do in case they suspect of a crime, is to notify the police and provide evidence, so it's investigated.
If they're allowed to kick people because some obscure software misidentified them as a criminal, I can envision a future where innocent people are unjustly and completely ostracized from all commerce within a city or country.
[1] https://www.milnerslaw.co.uk/can-i-choose-my-customers-the-right-to-refuse-service-in-uk-law/
Re: (Score:2)
They have a right to trespass anyone they don't like from the store. Apparently "the AI told me some nasty rumors about you" is adequate grounds for banning someone for life
Re: (Score:2)
> They have a right to trespass anyone they don't like from the store.
No, they haven't.
[1]https://www.milnerslaw.co.uk/c... [milnerslaw.co.uk]
[1] https://www.milnerslaw.co.uk/can-i-choose-my-customers-the-right-to-refuse-service-in-uk-law/
Correct alert? (Score:2)
"A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store," A "correct alert" would say that he was not a match. Are they claiming that they send alerts to the store for every non-match they find?
Re: Correct alert? (Score:2)
The alert said someone who kinda looks like that was a shoplifter. It's the store employee's job to verify a match which they didn't do. The tech is still bad but it didn't say he was a shoplifter, it said he might be and a human fucked it up the other half of the way.
Re: (Score:2)
But every person who sets foot in that store probably "kinda" looks like someone who has shoplifted. And since shoplifters look like everybody else, everyone COULD be a shoplifter.
Re: (Score:2)
I don't know, but that line bothered me as well. Too broad. It could mean that the system flagged him as "possible shoplifter, so keep an eye on him", and they misinterpreted that as "get him!". Or, "you weren't supposed to put his picture up".
Facewatch is a fake product (Score:2)
EVERYONE looks the same at about 50x50 pixels on a bubbled lens using a 10 year old camera. You really think to stop shoplifting, they installed an isolated network that can handle barely compressed 8K footage then put in all new, top res cameras? No! Those are $200 garbage quality cams mounted in the ceiling with warped lenses. Gee, I wonder why it can't tell people apart from that distance.
Have you seen the view of yourself that they broadcast at an American HyVee? It looks like a damn 90's skateboardin
Re: (Score:2)
If a product doesn't do what it claims, that sound like lawsuit fodder to me. 'Merika!
Trust But Verify (Score:2)
Facial recognition is really neat technology, and we are all slightly better off thanks to its development. It's also imperfect, and nearly-guaranteed to be a net negative if you fully trust it, without human verification.
If you want to come out ahead by using cool technology, you're going to have to think about how to use it. There just isn't any shortcut around thinking.
If you have something which is only 99.9% reliable, that can be useful but it's going to be wrong sometimes. How are you preventing that
Re: (Score:2)
The problem is, people have been over-trusting technology since technology was invented. Consider the '70s when corporate representatives were so fond on the phrase "But the computer says...". Yes, you could hear the bold italics in their voice, as if it was the infallible final word on everything.
If THE COMPUTER says you shoplifted, rest assured, some dolt in a suit will treat that like God's own word booming from the clouds.
Quote from the store and service company (Score:2)
> A Sainsbury's spokesperson said: "We have contacted Mr Arnold to apologise for his experience at our Dulwich superstore. The incident was caused by human error, not the facial recognition technology. Customers can be reassured that the Facewatch system has a 99.98% accuracy rate, and every match is reviewed by a trained manager." A Facewatch spokesperson said their technology was not at fault in this case. "A correct alert was sent to the retailer, but was subsequently subject to human error in the way it was handled in store," they said.
That's frankly bullshit. The system put a red ring around his face on the security monitoring system. The system told the employees to treat him as a shoplifter and as dutiful employees of their company with the system their company told them to use, they complied.
This is almost the exact same excuse made in the movie Brazil by Michael Palin's character Jack Lint, "Information Transit got the wrong man. I got the *right* man. The wrong one was delivered to me as the right man, I accepted him on good fai
I guess I won't be shopping at Sainsbury's anymore (Score:1)
The flaw here isn't that the software got it wrong, it's that a corporation is allowed to use it at all. What's next, cameras positioned to capture "legal" upskirt video because, of course, that's one of the best places for shoplifters to hide their stolen merchandise?
We need to let governments and corporations know that as citizens of a free country, we will not put up with mass surveillance backed by software that can track every individual person every moment of the time they are outside their homes, an
Re: (Score:3)
I don't understand why taking someone to court is considered "bad" or "American". That's a very civilized way to settle a dispute.
Re: (Score:2)
American and British laws are different. Most people consider it easier to win a defamation case in Britain, although the plaintiff does need to prove "actual harm" to their reputation. British law does place a high value on one's reputation.
Re: Be an American (Score:2)
Notably, fact is not an absolute defense like it is here. If your intent is to do harm then it's illegal, even if the harm is to a nonce like Saville, which is why it took so long to get him
Re: (Score:3)
Why is it that every Republitard answer to a problem is grift, corruption and ignoring the rule of law ?