Opening up 'Zero-Knowledge Proof' technology to promote privacy in age assurance
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Parents should at least be able to overwrite the age of their child, maybe selectively allow bypasses. My experience with a computer would have been completely different if I was blocked from half of the internet. Especially when I see which kind of content gets blocked.
We're building 1984 to protect from god knows what imaginary harms.
Stop putting plastic wrap around people's freedoms, liberty, and right to privacy.
We will look back at handing kids phones with instagram like giving kids cigarettes and think wtf were we doing.
In dealing with the ills of social media, you do what you do with every other negative externality - you tax it. At least the parts of it you don't like.
Designing privacy, freedom, and liberty destroying mechanisms is not the way.
Big social wants these regulations to pass so that they can get better identity tracking for ads targeting. To them it doesn't matter if the tech ushers in 1984. It makes them more money.
The argument, which has some pretty decent evidence behind it, is that prohibition is the thing that kills people. Because it has to be smuggled, dealers switch from "normal" hard drugs to overdose triggers like fentanyl with 1000x the potency because then they only have to smuggle 0.1% as much of it, which in turn kills people because street dealers cut it improperly and users get wildly different effective doses or drugs cut with dangerous contaminants.
Notice that meth literally is legal in the US. Essentially anyone can get amphetamines by going to a doctor and telling them you have the symptoms it gets prescribed to treat. It's even prescribed to kids. The primary barrier is having health insurance and the ability to take off work during the day every month to get a refill. Which is why the people dying of overdose are the people priced out of that system, who wouldn't be if they could buy it at Walmart, but because they can't they resort to the entirely unregulated black market and die of a fentanyl overdose.
Are you saying that we should let children smoke and just tax it because its better for their liberty and freedoms?
Or are you saying we should just tax social media for adults but banning it for kids is ok
A good example is the Jonathan Haidt/Aaron Brown fiasco from a few years ago. Brown has been methodically trying to stop the stampede off yet another pseudo-scientific cliff but not enough people are listening.
https://reason.com/2023/03/29/the-statistically-flawed-evide...
https://reason.com/video/2024/04/02/the-bad-science-behind-j...
https://reason.com/2023/05/30/not-every-study-on-teen-depres...
> In a recent article for Reason, I argued that the hundreds of studies that New York University professor Jonathan Haidt has assembled to support his claim that social media is causing the teen mental health crisis not only don't back up his claim; they undermine it.
Age verification campaigners like Haidt play a smooth game but consistently downplay how useless social science actually is for answering questions like this:
> I didn't express "concerns" about specific studies; I argued that the majority of the 301 papers cited in his document are garbage. I went through each category of studies on Haidt's list, chose the first one that studied social media and depression to get a random sampling, and then showed that they were so embarrassingly bad as to be completely useless. They were guilty of coding errors, fatal defects hidden in mid-paper jargon, inappropriate statistics, longitudinal studies that weren't longitudinal, experiments in name only, and red flags for hypothesis shopping and p-hacking (that is, misusing data analysis to yield results that can be presented as statistically significant).
It's possible that in the past few years a wealth of robust evidence has suddenly emerged but it seems doubtful.
This stuff does matter. If you misdiagnose the problem then congrats, you just let governments censor the internet - quite possibly creating a China style totalitarian system that pretends to be democratic along the way - and kids will still have the same problems. A bad outcome!
The interpretation is interesting. Probably, a lot of people don't like criticism of academia or have already made an emotional investment in the social media hypothesis, but aren't sure how to respond to Brown's critiques of the studies. So it just swings up and down with otherwise no engagement.
I wouldn't be surprised if 20 years from now we see social media as just another hysterical reaction that generated a generation of bad law, wrecking, or diminishing a number of lives, for no good reason at all.
Edgar Friendly got it right, back in 1993:
> See, according to Cocteau's plan, I'm the enemy. Cause I like to think, I like to read. I'm into freedom of speech and freedom of choice. I'm the kind if guy who wants to sit in a greasy spoon and think, "Gee, should I have the T-bone steak or the jumbo rack of barbecued ribs with the side order of gravy fries?" I want high cholesterol. I want to eat bacon, butter and buckets of cheese, okay? I want to smoke a Cuban cigar the size of Cincinnati in a non-smoking section. I wanna run through the streets naked with green Jello all over my body reading Playboy magazine. Why? Because I suddenly might feel the need to. Okay, pal? I've seen the future, you know what it is? It's a 47-year-old virgin sittin' around in his beige pajamas, drinking a banana-broccoli shake singing "I'm an Oscar-Meyer Wiener".
Sounds like denial or tunnel vision.
I mean, quite a few have come from proto-manosphere circles, too. Elliot Rodger comes to mind.
The fact that this is basically unheard of, while incels shooting up schools is somewhat common, may explain why blame is often thrown at one movement and not the other.
Citation needed?
Bollocks. European teenagers watch just as much porn and play GTA at age 10 and yet we don't end up having 12 children a day die from gun violence [1].
Note, I'm not an anti-gun nut, I think German and British anti-gun laws are ridiculously strict. But the American way of dealing with guns is equally bad.
[1] https://www.sandyhookpromise.org/resources/gun-violence-fact...
Note that this definition of "children" includes ages up 24 years old. Not that the US doesn't have a gun violence problem, but pretending 24 year olds are "children" in order to gain a better sound bite doesn't help anybody.
Then there are gun suicides which I would not count as gun violence, amounting to another 3.5 children + teenagers a day.
This is incredibly toxic for young men growing up and the women they interact with.
Some of the more prominent proponents are actual pimps (the Tate brothers).
This is a common media talking point, but are there any hard figures for this 'many'? The type you're describing existed when I was young, long before the internet. My impression of boys and young men today is that they are generally just as decent, cautious, respectful and idealistic as they ever were - but that a small crude and unpleasant minority taints the reputation of the whole generation.
The review talked to young people aged 13 to 19 and surveyed 1,000 young people aged 16 to 21. Over 6 in 10 (64%) said they had seen online pornography. Of these:
1 in 10 (10%) of nine-year-olds had seen pornography
3 in 10 (27%) of children had seen pornography by age 11
Half (50%) of children had seen it by age 13
4 in 5 (79%) had seen violent pornography before the age of 18, with the report stating “young people are frequently exposed to violent pornography, depicting coercive, degrading or pain-inducing sex acts”.
You don't seem to have any data putting your figures into any context over time: run the same study in the 80s and I would wager you'd see similar even worse results. Wank mags and grainy VHS were passed around schools from the moment they appeared, including BDSM and torture porn - often in the form of sleazy B-movies. Sure, pornography is far easier to access today. But the material is the same, and this notion that somehow, today's boys and young men are worse for this exposure than their predecessors is insidious and deeply ignorant.
It is significantly more difficult to find young men today who think it's acceptable for husbands to beat their wives - or that rape is never rape in marriage. Or who think they can get a woman drunk to seduce her. Campaigners had to work damn hard to raise public consciousness out of the traditionalist inertia around these blights. Frankly, to anyone like me, old enough to compare several different eras and their male representatives, comments like yours and the inferences you'd have people draw from them, are utterly ridiculous - and yes, hugely unjust to the overwhelming majority of young men who flinch from the idea of hurting a woman in bed or out of it, regardless of what type of pornography they've been exposed to.
No what's ignorant is ignoring the prevalence and nature of modern online pornography. Hopefully you realize that having the worst of what previous generations might've been exposed occassionally to by copying grainy VHS videos is literally a few clicks away now.
Much like social media it's pushed constantly onto them (well all us men). It's a giant predatory industry with a very addictive product.
It's not a reputation thing because it's about how destructive it is to society as a whole to both men and women. It's a very different sort of destructive behavior than previous generations might've had.
> hugely unjust to the overwhelming majority of young men who flinch from the idea of hurting a woman in bed or out of it
There's lots of great young guys out there. How about we not regress due by allowing new rampant destructive influences. That's my perspective.
We're seeing huge upticks in "incels" and "red-pilled" young men now. IMHO that's largely influenced by pervasive (mysoginist) pornography.
Even then, apparently young women don't agree with you as recent polls show young women don't view men favorably anymore [1]. So apparently something, or many things, are going wrong.
1: https://www.independent.co.uk/news/uk/home-news/women-men-fe...
Pornography may give some people some wrong ideas about sex and romantic relationships, might even instill some level of implicit misoginy in certain straight men, but I'm pretty sure you won't get the idea that women should be allowed in Parliament from watching too much porn.
There's many studies and organizations who publish warnings about violent pornography and young adults:
Dr Ruth Weir of City St George's, University of London, said extreme porn had been "normalised online" and was now "playing out in young people's relationships". [1]
It first posits that adult content has been normalized online, then cites unrelated statistics about abuse victims who had watched adult content. There's nothing that convincingly links that that first statement to the latter data.
It's at: https://www.childrenscommissioner.gov.uk/resource/pornograph...
To quote from that report:
A literature review of 19 academic papers, drawing on multiple methodologies since 2005, conducted by the Government Equalities Office (GEO) to assess the relationship between pornography exposure and negative behaviours towards women and girls found that pornography use had a statistically significant association with attitudes supporting violence against women (with violent pornography showing an even stronger association). [44] A meta-analysis of 9 studies found a significant association between pornography use among adult men and attitudes supporting violence against women, such as ‘rape myth acceptance’. [45] The association was found to be significantly stronger for violent pornography than non-violent pornography. Other studies involving young adults, including Peter and Valkenburg (2009) [46] and Hald et al. (2013), [47] have found that past pornography exposure among young males is significantly associated with less egalitarian and more aggressive attitudes towards women. This is particularly worrying when young people are being exposed to pornography.
Maybe there's lasting harm from engaging in them early. Or maybe it's better to get exposed to them early in your life, so that you have time to figure out why you don't want anything to do with them.
Either way, it seems pretty clear that preventing children and teens from engaging them is a nonstarter. You can't get anywhere close to consensus on "this is harmful and should be banned" because, guess what, someone's entire identity is going to be built around such communities.
https://en.wikipedia.org/wiki/Louis_Theroux:_Inside_the_Mano...
I think the basic error is that we're making a concession to obscene content and the sophists in our midst who have spent decades deploying the garbage of moral relativism and fallacious appeals to "freedom" to defend evil. The argument for age verification here is weakened if, instead, the production and distribution of pornography is outlawed.
That you cannot perfectly enforce the law doesn't mean the law has no value or function. The purpose of the law is not undermined by imperfect enforcement, and it isn't exhausted by enforceability. Law is a teacher. Anti-porn laws would still carry psychological and social weight. They are a declaration of what is not tolerated and what is not good and contributes to the stigmatization of bad things. That creates a higher hurdle in people's minds to seek out and engage in such activity and creates shame around such activities that itself dissuades.
I would also add that pornography and drugs have a history of being used in psychological warfare. Oligarchs ruining society? Allow pornography and it will absorb people's attention and cripple them emotionally and rationally to neutralize them. Or consider the recent loosening of drug laws or debate about loosing them - which I do not accept is coincidental - to give people another dulling and numbing agent and an escape. It is in the corrupt interests of an oligarchic elite to corral the herd. The police baton is painful and creates a dangerous indignation and resentment, but pornography and drugs do not.
Insane that they didn't even try this simple solution first. Yeah people will get around it, but they'll get around any solution.
Then the policy lives on the user agent.
That would be nice!
But if there isn't a safe market driven solution to age-verification, which provides anonymous, unsurveiled, age-attested site access, with no ability for the government to individual monitor, deny or revoke, then that is exactly what is going to get pushed on all of us.
You don't defeat an enemy by not needing the manacles they are very motivated to force on everyone..
Increasingly: We adopt zero knowledge proofs, and other decentralized open-sourced hard-security technologies, and resolve seemingly-small, but not-going-away practical issues like age & porn, or empower and "trust" every weak politician, interest group and stranger on the internet to not use our lack of awareness and defense against us.
Add AI to the mix, and the risk/damage of passivity becomes extreme.
- The age-gate should just be a setting on the device: either over 18 or under 18. Websites/apps should at most only be legally required to respect the device's assertions.
- Devices should be controllable by parents: let the parents decide whether the child should be age-restricted or not.
- Devices should have profiles so that you can let your kids use your own phone/laptop without messing up your stuff or getting into things they shouldn't.
Historically parents have been allowed to rent R-rated movies for their kids with nudity and sex and violence even if the video store isn't supposed to rent it out to the kids directly. That was always considered okay. If I think my 16-year old is mature enough to watch some porn, that should be the parents' decision.
Discuss what the experience was/is to zoomers and younger, especially girls. Did you try to play a silly online game with your friends while being constantly harassed by 3-4 adult men? How many times someone offered you money (in form of “lootboxes”) to get nude pictures of you when you were severely underage? Or was on every site you visited an algorithm pushing on your face content about how you should embrace anorexia, start gambling on what Trump says on TV, use drugs, or simply do a suicide?
Hey fellow unc’s, we really need to stop nostalgising on the computer childhood of our youth and listen to the kids (as well as a bunch of research on the topic) and face the fact that the internet of the friendly geeks and nerds of the yesterday does not exist anymore. Things have to change, if we want to have any kind of working society left whatsoever.
This is a huge shift that cannot be rectified by simple age filters.
Being realistic about the problem requires being realistic about ill-conceived solutions with conspicuous benefits for commercial actors.
Besides an array of largely static, non-interactive websites, there is no hard line between content that is suitable for young eyes and not.
and even if you think kids dont understand it enough to make that choice for themselves you should let parents do it. if a family thinks their kids can have unlimited access the government should let them.
thats where the california bill comes in as the only reasonable option. it gives families a choice instead of forcing restrictions on everyone and theres no privacy problem because its using self reported age data that stays on device. and i know you might ask what about kids who secretly buy a unrestricted phone with their own money. i think at that point they deserve to have it.
The fact is that we as a society have so far put the convenience and entertainment of adults before well-being of children and others, who are in the most weakest position.
https://blog.vrypan.net/2026/06/29/260629-whats-wrong-with-e...
...but they do? Google pay gives them your credit card and transaction details; any time your bank sends a statement to your gmail account, Google has that, too.
Am I missing your sarcasm?
Europe doesn't really have that status. Either you're known to the government and can receive documents from it, or you're a criminal in hiding, avoiding any and all government offices.
I have written a paper on how to do age verification in a completely privacy-preserving way, and it doesn’t even need zero-knowledge proofs:
I'm talking about complying with laws, in a privacy-preserving way. It's possible.
Here, I posted it on HN: https://news.ycombinator.com/item?id=48760492
Once adult sites adopt the system, it will creep over to any site wanting to limit their liability. Banks. Business services. Eventually almost everyone.
Liability the government will dramatize and escalate. You won't see the government pass any laws to create age-liability safe harbors.
Wikipedia is already being forced to fight to not implement age verification. Age verification managed by the government = No Wikipedia access without individually tracked, controlled and revokable government permission. [0]
Seldom has a slippery slope been so slippery.
The distance between government controlled per-citizen access to obviously adult sites, and government permissioned/controlled access to any site of substance, does not even involve a technical hurdle. It just becomes a site adoption curve. Every adoption increasing the scope of real-time government surveillance in our minute-to-minute lives, and its real-time at-will ability to deny access to whatever it chooses, whenever it chooses, and for whoever it chooses. In any combination.
Dystopia is here.
In my opinion, this is terrifying.
We need: Third party attestation, providable by anyone/entity meeting basic openly-defined criteria, limited to age attestation only, implemented with Zero Knowledge Proofs, to create a safe anonymous (unsurveiled/no personalized denials) alternative, to take the wind out of the sails of this constant governmental power grab. If it isn't solved by security minded technologists and the marketplace, the freedom destroying version will prevail - and it won't be undone.
[0] https://www.eff.org/deeplinks/2025/07/we-support-wikimedia-f...
But apparently are unaware that this debate is being forced by powerful unreasonable people who are not going to give up if we leave a resolution up to them.
Reasonable and informed people want to avoid that. By stronger means than repeating “I don’t need that” until we realize that didn’t work.
When a site you and i need requires you and I to register with our governments to access it, how is your reasonable opinion going to help us navigate that?
Identity attestation isn’t a bad thing per se. It’s just something that can be abused.
Banks already verify your identity as well and don't require you to use a government app.
Law enforcement asks for your ID and check it with their database, which is already enough as well.
We don't need age attestation for accessing websites.
This needs more emphasis. Once we make (even zero-knowledge) proofs convenient and common, it'll spread, and soon it won't be just age that's getting assured.
First it's 'over 18?', then it's 'over 25?', and then 'biological sex?', 'employed?', 'enjoys posting on HN?', 'active in the early morning?' and after half a dozen questions, all with binary answers that are safe individually, you can zero in on a 23 year old woman who has a job and posts on HN in the morning.
Ask a few dozen questions like that and you'd be able to sieve an individual from a group of millions, especially if they're unlucky enough not to be absolutely typical.
Obviously if you see a bunch of proofs for known circuits coming from the same IP address then yeah, you can infer a bunch of info from that metadata.
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in theory. How do you do that on paper? How do you "anonymize" this data, to make it so they aren't related to each other?
This is just like Facebook implementing the Signal protocol on WhatsApp. They technically can't access your messages, but they have all the metadata which most of the times will allow someone to infer the content of the conversation.
And does it make sense that at least some people do want your identity before interacting with you?
I'm afraid "age assurance" has nothing to do with "the children".
and you should be afraid, very afraid. Because none of these (and other measures to invade privacy) has ever had anything to do with children.
It is not, because your premise is false. This whole thing has been going on for as long as kids have been online. The early 2000s tried (and obviously failed) by using credit cards. The UK tried and failed last decade to ban porn for minors this way. AI tools are probably not even on the radar for the kind of politicians that keep pushing this.
Forget about the politicians for a bit. There still are many regions on the globe where no age verification is mandatory, yet websites chose to implement it anyway. Why, if not for tracking and bots?
You can both give a proof your age and not lose privacy.
Why the hell do I need to login to my digital wallet to access a fucking website???
The irony.
Before snarkily calling "irony", at least understand the topic of discussion and make appropriate comparisons.
P.S.:
Not only is your assumption false, since in its first years the web was only accessible to academics so the gating was implicit, but the internet itself from its beginning to the present day requires heavy governmental intervention and international collaboration to make it work. Do you know what's behind the cables that carry your bytes? The ICANN? The IANA? I hope you never do, if you dislike government involvement this much
I know, and neither am I. Perhaps you misread my comment.
> I couldn't care less that the web has not been government-gated for the past X years
That is clear.
> because through this logic you should adhere to any dumb tradition or custom humans have ever had
Not only is that statement a non-sequitur, since neither of us is making an argument based on tradition, it's also entirely irrelevant.
> I am concerned with the present and the future of the web's impact on the world, which of course requires government intervention like any other big phenomenon or technology in the history of humanity.
An assertion that is a) going beyond the subject, thus creating a straw man, and b) when applied to that actual subject, completely undermined by my comment.
My actual comment, not the one you appear to have decided to respond to that I haven't written, wouldn't write, and thus doesn't exist.
> Not only is your assumption false, since in its first years the web was only accessible to academics so the gating was implicit
The subject is *explicit* age gating. Nothing implicit, and nothing that isn't age gating is relevant.
> Do you know what's behind the cables that carry your bytes? The ICANN? The IANA? I hope you never do, if you dislike government involvement this much
Firstly, that is snark, but fair's fair I suppose. The irony.
Secondly and much more importantly, I dislike age gating via large-scale government coercion, the subject of this discussion.
Could you respond to that? Specifically, age gating via large-scale government coercion.
Since the government currently has all of our ID data and since mathematically secure algorithms have been invented to prove personal information without revealing it, I'd say we have reached the point where digital identification can be implemented without infringing on people's privacy any more than a clerk checking your ID.
> Operating a motor vehicle requires a license, and you have to present it.
You do not have to present it in all cases, and not to actually use the vehicle.
> Drinking and other activities and purchases require showing ID to prove your age.
Not in all cases. Purchasing alcohol in the UK may require ID (but again, not in all cases) but drinking is legal above 5 years old in areas that are not solely for the purpose of selling alcohol (crazy, but true).
That list will go on.
> Since the government currently has all of our ID data
No, it does not - for example, a passport is different to a birth certificate and they contain different amounts of identity information, and my government does not need to know other identity info regarding my work.
> mathematically secure algorithms have been invented to prove personal information without revealing it, I'd say we have reached the point where digital identification can be implemented without infringing on people's privacy any more than a clerk checking your ID.
This is too strong a statement. Having strong algorithms does not equate with the level of security you claim to exist. Implementation of the whole process is just as important.
Regardless, we have plenty of good reasons to fear any government having this information. The Japanese government, for example, has its civil service set up in a way to prevent the kind of abuses we saw in WW2. I wouldn't be surprised if the Dutch have done the same, for what should be obvious reasons.
The authentication requirements for some web pages have exited for a long time.
If a company can come up with a reasonable reason to check something, then a ZKP enables that check without wider harm to privacy. But it still gives the narrow harm to privacy that otherwise wouldn’t exist.
Put differently, privacy concerns have shielded us not just from surveillance, but also from powerful control. Control in the form of “you are only allowed X if you meet criteria Y”. With ZKPs, that shield of “why would I tell you enough information to determine Y” stops working. But those conditions on X are harmful more broadly.
Take the US border checks of Social Media. Are those more OK if all of a sudden there’s a ZKP you have to give of never having called Trump a cunt in any private message?
I'm not into this topic, so maybe someone else can answer this: How "zero-knowledge" is this actually?
As far as I understand, there are three parties here: 1. Me, the user; 2. The site I want to access; 3. The attestor (google? my government?). What do they know about each other?
Does the site know who I am?
Does the site know who my attestor is (and therefore, for example, that it doesn't like Winnie-the-Poo memes)?
Does the attestor know what site or kind of content I want to visit (and therefore e.g. if he agrees with it)?
Does the attestor know who I am?
Do I always know who the site and attestor are, and when this proof happens?
the system is valid zkp but any of the services in practice can still collect personally identifiable information from their users.
There is also nothing stopping the attestor to collude with the site you want to access, to reveal information about you.
Also, nothing stops a site from having a flow like: 1. Please enter your age 2. Verify that it's correct using a proof
The zkp is valid as far as the tech is concerned but the sites can still do whatever they want.
* Does the site know who the user is: No. That's the entire purpose here.
* Does the site know who the attestor is: Yes, they need to validate asymmetric crypto on the proof, so they need a list of public keys (which they can attach attestor identity to).
* Does the attestor know what kind of content I want to visit: They should not. With the JWT you can validate without telling the attestor which user's proof you validate. OTOH, if there's some "is this one revoked" type of API one could easily re-introduce such an information channel on accident.
* does the attestor know who the user is: Yes (or at least have some bits of information about you they are willing to attest to others. In practice assume it's Google/Apple/MS with information associated with your account, or your bank or ...)
* Does the user always know site/attestor: From a technical perspective yes. From a practical human one... doubtful.
--Googler, though far removed from this project, so no internal knowledge.
First, the attestor is not google. Google here only provides the infra (to generate proof and verify them). Let's call the attestor the issuer, and it's the trusted authority that gives you a proof of identity.
A possible flow is:
1. (pre-req) Some issuer (a state, bank, mobile operator, etc.) issues a signed credential to my wallet (stored on my phone, for instance). This could be a full digital ID, or a narrower “proof of age” attestation.
2. Later, a site asks my browser for a proof that I satisfy some predicate, e.g. age >= 18. The site provides the "zk-program" (circuit) that needs to be executed, and awaits for proof (which are essentially proof of executions of the program on trusted yet undisclosed inputs).
3. My phone generates (ideally locally, but not ready today yet) a ZK proof that it knows a valid issuer-signed credential whose hidden attributes satisfy that predicate. Essentially, it is executing the circuit with some inputs (some are public, like public key of issuers, some of private, like the issued ID)
4. The site verifies the proof against public inputs: the issuer public key, the circuit being used, the predicate being requested, and a fresh nonce/challenge.
So to answer some of your questions.
> Does the site know who I am? Not from the ZK proof itself, it will know who has issued your ID.
> Does the site know my attestor? Yes, it knows their public key.
> Does the attestor know what site I am visiting? No.
> Does the attestor know who I am? Yes
> Do I know who the site and attestor are, and when proof happens? I guess there are multiple possible ways to do this, depends on the UX.
1. The site does not know who you are. This is the whole point. You generate a mathematical proof you possess a valid government ID that says “age >= n”
2. Yes. You are generating a zkp based on information anchored by the attester. In this case the ID issuing gov. That attester can be something other than a gov, but zkps are a bit useless if the site doesn’t know what exactly is being proved. In this case you are proving “I possess a government ID saying age >=n”. You must know about the government to care about this proof.
3. Not in this case. The attester only knows it has issued you an ID, but does not need to be further consulted. You could certainly construct a scheme such that you require a ZKP of recent written permission from some entity, but this is not inherent to ZKPs.
4. This is a UX question. If the ZK wallet and website are implemented in such a way that it’s always displayed when a credential is requested and what credential that is, then yes.
Can they map which places requests which person?
Then when you want to access something age gated, you locally generate a proof that says “I have a credential signed by X, with DoB N, and N < CutOff date” where X and the CutOff date are public but the credential and the value N are hidden through the ZkP.
The attestor isn’t involved so doesn’t learn anything. The Verifier only learns the public information, and generally won’t be able to tell if two proofs are made with the same credential.
And the answer to that is a resounding no. As long as you can run software of your choosing, then it is trivial to proxy a zero knowledge proof such that a third party can provide proof of the given property for you to use. If the system is really zero-knowledge, then that third party will suffer no repercussions for defeating the purpose of the system. And we can easily imagine people willing to provide this service (for ideological reasons and/or simply payment).
To be secure, all of these schemes rely on an unstated assumption of remote attestation that will prevent users from running their own software. Locking down computing is Google's basic agenda, but saying this would make the systems less appealing to people, so they obviously downplay it.
(I found a list of requirements for them here: https://eudi.dev/2.4.0/annexes/annex-2/annex-2-high-level-re... )
https://www.youtube.com/watch?v=fOGdb1CTu5c
This video is very beautifully explains it
That might seem to be the issue, but it is a red herring.
Powerful people are ramming age verification through in a way that will surveil you and give government the ability to not just attest for your age, but surveil what sites you use, and revert their attestation, for anyone, on any site, for whatever reason.
Not just porn sites but any site they convince to use their age verification scheme.
Even Wikipedia is having to fight this with the help of the EFF to not force all its users to submit to this.
Wake up. We all need to wake up.
The purpose of an anonymizing open source alternative is to head off dystopia. Nuanced opinions about parenting are not a defense strategy. Not against a closed internet permissioning system run by governments. Implemented by people who are using parenting as a cover.
Your parenting opinions won’t help you log onto increasing numbers of sites that block you without a government supplied key.
Wake up.
We must not let governments use this issue to lock down the internet. But that is now the default outcome.
The problem is insidious.
> Today, we open sourced our Zero-Knowledge Proof (ZKP) libraries, fulfilling a promise and building on our partnership with Sparkasse to support EU age assurance.
Done.
I made a formal submission to the Australian Government in the very small consulting window they held for the Access and Assistance bill. Pleading with them to consider simply not introducing the law, as there was no justification for it at all. Google also made a submission against the bill, as did many large local and overseas corporations.
The government went ahead anyway.
What are the chances of me swinging any government when Google et al are on the other side, determined to provide privacy and anonymity destroying products to bolster their bottom line?
Probably worth mentioning that the Access and Assistance bill permits the Australian government to secretly (even just verbally) compel anyone building age assurance technology to secretly backdoor it to collect metadata, or any other information they choose. There's no level of safety from the government one can achieve with any app. If they resist they go straight to the Australian version of a secret national security court. The bill doesn't even make it clear whether briefing their solicitor about the request is legal. It doesn't matter how good the crypto is if the app is recording details outside of that. Its all just theatre at this point. There's no safe app, so we should completely resist all attempts to do things the government could restrict, leak or misuse.
I dont see how this is even slightly contentious in the year of our lord two thousand and twenty six, after decades of leaks affirming governments do this stuff, decades of governments and corporations dangerously failing their citizens privacy, when a particular government is hell bent on using all the personal data it can hoover up to persecute migrants and refugees. How are people blindly monofocusing on the crypto while trusting everything else?
Age assurance is being used in more than a single scope. I dont disagree that the revolution isnt happening, but theres no need to be so reductive.
>Of course the social media companies object to their product being banned. It's like cigarette companies objecting to plain packaging.
They aren't objecting to age assurance tools. They are objecting to the current ham fisted model, but when they can organise something less nebulous than the current regime they will be fighting to implement it first.
So I have little sympathy that the resulting laws are not optimal for them.
It was solved. Dont collect information.
The problem is making shitty psychotic apps, not determining who can use them.
I would much rather they cut meta into pieces and sold them off as scraps, than just scarfing up the PID of the users to make arbitrary determinations about who can have what brainrot.
There are more people than just you (and other tech literate folk) online.
I would also rather meta be cut an sold of as scraps. This is sadly not the question being framed.
I’ve dedicated a portion of my life volunteering to moderate content in communities. It is an unmitigated shit show. The status quo is great for firms and corrosive for society.
If theres a takeaway from this sub thread, is why “meta being broken up and sold for scraps” not being raised as a question in the first place.
Is it another case of too big to fail?
It was solved for everyone for a long time.
>There are more people than just you (and other tech literate folk) online.
And if you bury the algorithms a lot of the other people will simply go away.
>I’ve dedicated a portion of my life volunteering to moderate content in communities. It is an unmitigated shit show. The status quo is great for firms and corrosive for society.
I stopped doing so over a decade ago. 9/10 other moderators are trying to win some kind of parasocial relationship with owners/developers/whatever. I have seen really good teams moderating really well, but they are the exception not the rule. I don't think anything proposed in this thread has any bearing on content moderation one way or the other.
>If there's a takeaway from this sub thread, is why “meta being broken up and sold for scraps” not being raised as a question in the first place.
The government and advertisers are addicted to the data that it generates. The social graph has basically replaced humint entirely for security services. Most of the defense against terrorism these days relies on idiots sending facebook messages with the details of their plans. The successful terrorists are now the ones that don't have meaningful friendships to blurt their plans out to. Its our panopticon, and "Too big to fail" doesn't even begin to describe it. Its just a matter of time until a western nation uses the data to persecute minorities, heck some people think the US government is already.
Which is why giving them more data to hoover up isn't a solution. Advertisers are squealing right now because so much content and engagement is completely fake, and they are worried about losing even more money if age detection systems add any more friction to usage. But the security agencies, the silent partner, are just patiently waiting for the kinks to be worked out.
reddit isn't the vast majority of the population, fren. it's 1% of 4%.
unless you've got polls you could show to back up your claim? polls, not opinion pieces. polls asking unambiguous questions like "are you in favor of banning social media?" or "are you in favor of age verification laws?", not vague ones like "are you concerned about the content your kids might see on the internet?". got any of those?
https://yougov.com/articles/51000-support-for-under-16-socia...
This was in 2024, since then the attitude is still very much that kids should be taken off social media, but that the current restrictions aren't yet working as the face scanning verification is easily bypassed.
Look at the 2023 referendum.
When something is fed to us by the media, and supported by both ALP and LNP there's rarely ever public dissent. The risks of age assurance weren't given any public airtime. The few criticisms that were put to the government were shrugged off as "oh it might start working later".
Probably a comparable issue would be the MyHealth Record nonsense, where the existence of the platform was largely uncontentious, but the change to make it opt-out rather than opt-in was actually put to public debate and once some day light got in, a significant amount of people opted out.
> Support among parents for a social media ban for under-16s is highest in Malaysia (77%) and India (75%), Argentina (55%) and lowest in Japan (38%) and Nigeria (39%)
> Globally, the majority of Gen Z (51%) – the first true digital natives – support a social media ban for under-16s. Support for the ban is highest in India (73%) and UAE (67%), Argentina (54%) and lowest in Japan (28%), UK, and Canada (both 40%
https://www.varkeyfoundation.org/post/6-in-10-parents-worldw... Support among parents for a social media ban for under-16s is highest in Malaysia (77%) and India (75%), Argentina (55%) and lowest in Japan (38%) and Nigeria (39%)
increasingly few people are parents, so these numbers are don't reflect 'the vast majority' of the population.
the latter wouldn't surprise me at all, I've seen all kinds of degenerates suddenly begin to act like boomers after they've had a kid.
> I dont see how this is even slightly contentious in the year of our lord two thousand and twenty six
Violent revolution in response to data privacy issues?
Done.
Politicians don't want to be seen as going soft on child predators and harms to children. That is a career-ending move. Whether the bills they introduce even protect children at all has no bearing on it. PR is PR.
If you're essentially telling somebody that children don't need to be protected, you might feel smug and superior, but you're achieving nothing. You'll be ignored as a conspiracy-theory-loving nutjob.
If, on the other hand, you tell politicians that there are multiple approaches to protecting children, all as effective, with one of them having fewer side-effects to the rest of society, now that's a much easier sell. You sound like somebody who knows their stuff and has a nuanced take.
Government is these days largely solved, and for politicians that's a horrendous untenable situation, so they have to keep inventing problems to solve.
All they do is stack law on law on law for no discernible public good, with only negative outcomes.
The problem is the framing of the problem. Its not "How to protect kids online". The problem is "how to protect everyones freedoms online". And the only way to do that is to say absolutely not, every single time this shit comes up.
And its disingenuous to say the least, to assume that these tools are only coming for kids on social media. These tools are coming everywhere, to everyone. You just let them in because they played the old "wont someone please think about the children" song and dance. This exact nonsense was how we got the eSafety commissioner, who was brought in with a mandate to scrub the video footage of the christchurch massacre off of the internet. Of course, now they spend a large amount of time and money trying to get all sorts of posts scrubbed off the internet, often in jurisdictions that have free speech mandates.
Doesn't seem like government is taking any steps here to try and regulate anything anymore. Possibly not ever again.
But not "...without sharing anything else even when setting up your token."
Can I prove that some cryptographic token A) doesn't contain any PII and B) that the token itself can't be used as an ID tied to my identity in a Google or government database?
No and no. So, I do not support schemes like this.
See section 2 of this document: https://eudi.dev/2.4.0/discussion-topics/g-zero-knowledge-pr... . If there are any objections that this is not technically feasible to achieve in practice, I would like to know what they are.
(Also, AFAIK, setting up such a thing would comply with any of the age-verification laws that are being proposed around the world. You could even set up this as two arms of the same company and be able to prove to your users that while you've seen all their IDs, you cannot link their usernames to their IDs. This still isn't the best because you're still handling their PII with associated risk of leaks but it's a lot better than anyone is doing ATM)
I suspect the ZKP proof or token is practically unique and related to you, so I could be personal data if you use the definition from GDPR.
With ZKP the entity and the original verifier shouldn't be able to match your identity to the ZKP proof or token, but the app on your phone of course can do that.
The app probably will be made some government contractor and there is no technical measure that would prevent them to just share all that data with whoever they want.
It works for contract signing and payments, because there is a built in incentive there, but not for age attestation.
As always with tracking, the value is in the metadata.
The knowledge if you are or are not above a certain age is already privacy invasive but not that relevant for tracking or ads.
But with ZKP at least you won't need to send your creditcard, copy of ID and address to the 3rd party to verify.
All current age verification measures open up a torrent of attack vectors on user PII and privacy. Limiting the number of entities that are able to access data is one of the best ways to prevent it's leak or abuse. Don't let perfection be the enemy of good.
But therein lies the fundamental problem with surveillance capitalism. Until the sale of personal data/metadata is outlawed, the practice of targeting content based on an individuals personal data/metadata is outlawed, there is a highly punitive cost for violations and leaks that make storage outside core business functionality a major criminal and financial risk, and the compilation of this data by "intelligence" agencies it treated as a critical attack vector to national security – the attack on each citizens civil rights that it truly is – most privacy laws and regulations are just virtue signals designed specifically avoid the root causes, and further entrench the power of monopolies and incumbents.
FYI I don't believe Google sells user data. They sell products which leverage user data to give them a critical advantage over every competitor who does not have trackers in everyones pockets/computers, does not store their entire web search/browsing history, etc. It's in the interest of big tech to protect their market advantage (like ZKP, which would prevent competitors from having a new gov-mandated vector to compile user data).
I get that ZK techniques work, and reveal "nothing". That's useful.
But if they reveal nothing, isn't it wide open for abuse? Couldn't one over-18-person's proof become everyone's proof, because they can't tell it's the same proof, and the issuer can't tell where or how often the proof is being used? Or are there ways to construct data leaks that are not user-identifying but are abuse-identifying (and what would that even mean)?
Yep!
This is why the concept of zero knowledge age gating is such a trap for technically minded people. They imagine receiving a private cryptographic object that can be used to anonymously confirm that the government says it was issued to someone over 18.
That’s completely useless because a single leaked token could be used forever, so nobody actually considers this.
All of the real proposals have various compromises baked in. Some people want to require device attestation, so you could only do this handshake from a government approved device running a government approved operating system. Forget using Linux or maybe even a general purpose computer at all.
Other proposals involve online government handshakes in various ways, with a pinky promise that the government won’t keep logs or tap it for national security purposes. So we get back to anonymous by trust only.
:(
The governments’ focus might be on protecting genuine users (adults or not), not fighting fraudsters.
In other words if ZKP works for the vast majority of technically illiterate people with their EU ewallet, the job is done.
The reason this is a non-problem for the purpose being discussed (age verification on social media) is that you can simply allow anyone with a de-Googled phone or using Linux on a laptop (or even Mac or Windows) to bypass the age check. You don't need a 100.0% accuracy solution, anything above 90% is fine.
Essentially all teenagers are using social media on Android or iOS with apps from the official app store. If you make social media unavailable only on those devices, they are not going to be switching en masse to SailfishOS or start to carry around backpacks with laptops.
Maybe a few will. But then they're going to be very lonely on their social media and subsequently stop caring.
Social media is something people want. A large part of why people buy smartphones in the first place (especially at that age) is to be on social media. If you need to buy some weird kind of smartphone to do it, or ask your tech-savvy friend to do some voodoo on it for ten bucks, people absolutely will do that.
See the story of console modchips in eastern Europe for an example. Legal games were so expensive at that time that most kids / families weren't able to afford them. Console modchips existed, but they were difficult to install, and most people just didn't have the expertise. What ended up happening was that everybody "knew a guy", and that guy would do their modchip for a fee. They didn't need to know anything about rooting, ROMs, flashing or soldering, they gave a legal console to somebody and got a console that could play pirated games back.
Motivated kids can find a way! Perhaps evading age gates will produce the next generation of hackers.
There's an interesting post here which goes into some of this - https://blog.cryptographyengineering.com/2026/03/02/anonymou...
So -
> Yep!
Actually nope.
Which turns into a handshake with the centralized entity, the government.
If every token is single use then you also need to get them all from the government, either on demand or in bulk. They can then be sold.
SPOT ON! This needs to be plastered across the top of every single thread on "age verification" (really: identity verification).
Talk of "zero knowledge proofs" or other technical schemes are essentially just nerd sniping on this topic. These sound like really cool solutions where we can have our cake and eat it too, but the reality is that the cool technical bits are just the tip of the iceberg. For them to actually be secure (ie prevent the trivial proxying of credentials), there has to be another, much more draconian, part to the system.
Even if that part is missing to begin with, then calls to add it down the line will be inevitable once the idea that websites are responsible for verifying users "ages" (identities) has taken hold and those flaws become glaringly apparent.
I am a parent who will be staring down this issue in a few short years. The Internet is not the place we grew up. Faceboot and other engagement-farming companies are most certainly malevolent threats to the human psyche [0], and it's reasonable to assume that their effects are even stronger on developing minds.
The only approaches that are workable to protect kids as well as preserve Internet/computing freedom (which is actually an additional angle of protecting kids from continuing loss of freedom to roam) involve the client device being responsible for what to block/show, with information only ever flowing from the server to the client - for example tags that assert a site/app is suitable for people over a given age, and on-device parental control software that operates on those tags. If parental controls are enabled and a website has no tags, then the site does not display - failing closed and preserving compatibility with the open web.
Given that this is a dire problem that parents face that has reached a tipping point, it would be reasonable to create a legal mandate that mass market device manufacturers must include parental control software that can be enabled during setup process, and that websites over a certain size have to include tags stating their age appropriateness. That would bootstrap the ecosystem and lead to the development of more vibrant tags and blocking software, enabling parents to set their own policies independent of corporate attorneys decreeing what is acceptable for their kids.
[0] It is also worth keeping in mind that it is exactly Faceboot and its ilk that are pushing these identity verification laws in the first place! They are simply trying to remove their legal liability for harming kids, so they can otherwise continue business as usual
Attackers could still compromise the system with proxies, but you can fix that by (a) passing in a random sessionid from the server so proofs can't be replayed, (b) also passing in the server's public key, so a MITM attack will result in proof the server can't verify, and (c) as you mention, using secure hardware on the client, and encrypting communications between that hardware and the server. The secure hardware doesn't have to preclude general-purpose computers; it can work like a yubikey or hardware wallet, just plug into USB or bluetooth.
Without proxies, a leaked key has a minor impact unless it's widely distributed online, in which case it's easy to notice and add to the revocation list.
Tracking clients can be prevented if the client generates a new public key for each session.
Requiring hardware is in one sense a downside, and strong protections for access would have to be part of the law. But giving everyone secure cryptographic hardware that can do key management and zero-knowledge proofs would be a huge improvement for everyone's privacy and security, so it might be a good trade.
And now you can use time correlation attack to unmask people.
You could build a merkle tree to say "we exist after X" but not "there is no other X". And publishing that tree for verification would seemingly violate "zero knowledge", unless you know of some way to scrub that, and also hide timing information, because timing information can identify visitors to observers.
- you enter ph and must age-verify. It says 'your secret: "capable peanut", enter age proof below'.
- you go to age-knower (e.g bank or government page). You provide the secret phrase, and you get back a cryptographically signed json with the secret phrase, a claim 'above18', and a field stating who attested for the age (e.g government or bank or whoever).
- you paste this signed json (maybe encoded as base64 or something) into ph. It will verify that the attestee is good, then use it's public key to verify the signature, before checking that the secret is the correct one, and that it contains the age-claim.
Is the problem that if ph and the attestee colludes they can compare the secret string and figure out who you are?
For some isolated scenarios, that collusion risk may be completely fine. But not for something that is poised to control access to the internet as a whole, or in any way relates to maintaining safe free speech on the dominant public platform for doing so (the internet). People need protection from their government (present and future), or it's not a "right", it's just temporary retroactively-revokable permission.
See https://educatedguesswork.org/posts/age-verification-id/#dev... for some more detail.
When you want to provide information from that document to a third party a protocol is used which allows you to demonstrate to the third party that (1) you have a document from the government bound to your hardware security device, (2) you have unlocked the hardware security device, (3) and the document says what you say it says (e.g., "the birthdate field in this document contains a value that is more than 18 years in the past").
This third party gets no additional information about the contents of your document. The protocol takes place entirely between your device and the third party, so the government that issued you the bound document has no idea when or if you use it.
Someone over 18 person could indeed decide to help others prove age, but they would either have to do it in person or be willing to loan their unlocked security element to those others.
You can still automate age-verification-as-a-service using a physical autoclicker on a smartphone with the camera oriented at a screen showing QR codes. I expect this to happen, and for that reason I also expect true anonymity to be something that will last a year or so until it will be politically decided to fix the issue using some central party that verifiers have to contact to impose rate limiting.
1. Imagine what the protocol would look like without privacy (zk allows you to “sign” a computation, so just do the computation in the clear)
2. Imagine what the protocol would look like by revealing a hash of the passport only (the idea of a “nullifier”, a unique identifier that hides the data and and can be revealed to prevent replays)
The first one should already answer your question: the way you would prevent replays or portability (I use your proof) is to attach some sort of session context to your proof
Your proof proves two claims. That the person proving their age is over 18, and that they're using a device and software that hasn't been tampered with. That software requires human presence at every age check.
ZKPs for age assurance are trading off privacy at the expense of software malleability.
Note that this has nothing to do with open source; it's perfectly fine to release the source code for the relevant software. You can even allow for reproducible builds and full auditability if that's what you want.
The released code can do all of that, and then nothing still assures me that they didn't implement just a POST <my whole information> to their partner and called it ZKP and pointed at google's repo.
But note that it does have everything to do with software freedom. Being able to read the source is little consolation if you're unable to modify it. And preventing users from using modified software is the entire point of remote attestation.
"Zero-Knowledge Proof" based schemes for this problem is nothing more than a marketing scheme by Google to continue locking down devices and the previously-open web ala WEI, SafetyNet, etc. https://news.ycombinator.com/item?id=48760232
Good point, they do contain more information than "They are over 18". The primary (usually only) thing is who is attesting they are over 18. That might be the government, or a bank.
That's inevitable, because the usual flow is rather like Google's OAuth - the site needing you to prove your age rediects to the provider (Google, or whoever), who asks questions to verify your identity, and then replies with "over 18" or "not over 18".
This can leak other information aside from the site knowing who is verifying your age. For example, done the wrong way, the Google / the government could know what porn sites you like. OAuth, for example leaks that sort of information. But there is no technical reason it has to be that way.
The major barrier to all this isn't whether it's possible to design a protocol that proves your age, having a driver's licence or even an amount in a bank account. It is absolutely possible. It's that to be useful, everyone has to agree on the same protocol. That has so far proved to be near insurmountable.
This is false. There are many problems with age verification, but the EU approach does not involve the id provider in the verification flow. The site requiring verification presents a QR code which encodes a presentation request and the provider controlled URL which is to receive a presentation of the age credential, and then the smartphone generates a unique presentation signed by a device bound key and sends it to that endpoint.
It is however true that in addition to the one bit of information saying age>18, what is also revealed is the public key of the identity provider. This will at least reveal the nationality of the credential holder and - in the case there are multiple issuers within a nation - may reveal even more information about their demography.
The nit you look to be picking is "redirect" means "a web page directs your browser to go to another URL". That is an interpretation you could use, but I was using a broader one. In the EU case, it isn't the browser following the redirect, it's you. The "server" you are redirected to is a government-provided app on your phone that implements openid4vp. But the underlying principle is still the same - you are "redirected" to a third-party proof-of-age provider, who sends a reply signed by the provider.
To the OP: openid4vp is an example of a protocol that is about as private as you can get. It all works offline, so the government does not know what sites you have visited. And the age verifier has no idea who owns the phone. As you say, the connection between the phone and the person holding it is a weakness; junior could just borrow big brother's phone to prove his age.
I'm not a fan of technology fixes for social problems but i do think this may be in the sweet spot.
I see a lot of people here don't agree. I think they may not appreciate quite how concerned a lot of the community is about the effects of networked communication on minors. I'm not here to change people's minds, but this isn't a US problem it's a global one, and US constitutional rights views do not predominate worldwide.
Google has more customers outside the US than inside, and has more business with entities subject to non US laws than solely US domiciled entities.
I hate to be cynical but I worry that this isn't going to matter, because it really seems that a lot of the pressure behind age verification isn't actually very interested in the age verification part...
But a part of me wonders if this may be by design from the debate moderators - if a technical expert opens up by saying "we have a cryptographically secured solution that is backed by experts and privacy advocates alike", what's the next 45 minutes of the TV show going to be about?
> How about not needing to do age verification?
Which I agree with. However, I think that ship is sailing. Those who care about this had better find a provider that they trust and support providers they trust, because the perfect is the enemy of the good, and without the good there'll be no way to rollback to the perfect at all.
I just posted a general solution anyone can implement without needing Google as the trusted dealer: https://news.ycombinator.com/item?id=48760492
I wonder who or what will abuse this infrustructure when they fail.
When not doing privacy oriented cryptocurrency (cough money laundering cough) with ZKP's, if you really want private verification you are in a position where a single actor can authenticate the entire world and no one will know it happened. And to prevent it you assemble the pieces necessary to deanonymize anyone.
Make no mistake. ZKP age verification, as proposed, will just require multiple parties to collude to figure out your identity.
They can't even implement ZKP for remote attestation due to the auth-the-world problem.
So you should assume the government can track you, because you should assume both will be streaming those identifiers to it.
Ideally, no age verification would be required or proposed. However, if it is, this implementation should be the base minimum, should it not?
This is a gazillion percent better than a foreign corporation being in charge, isn't it?
I need to not HN after beers.
It's moving the goal post from one entity to another.
You can also fake it by letting someone else solve it for you.
Fair enough, that's true. But there is no solution that could ever prevent this, right?
I find the naming and the way it gets sold wrong because of it.