Cops routinely use possession of a target's ID as a detention method during traffic stops.

I rather suspect we'll see begin to see stories of substituting phone possession if this becomes widespread.

Related... do "I've been pulled over" recorder apps continue to run while this is active?

People need to accept that the moment you’re face to face with a cop, software isn’t going to restore accountability on the spot or give you an edge against an adversary that has the monopoly of violence. If your threat model is that you should be prepared for a cop to seize either your physical driver’s license or your phone, you should make sure you carry the one you care the least about with you.

The intent is that you tap the phone on a reader and that it doesn't leave your possession.

In many locales they will not be able to retain a phone legally without court order because of laws/rights around search-and-seizure.

Unlike a state-issued ID, the understanding is solidly that the phone is the citizen's property.

> legally

There's the problem. Cops do plenty of illegal things all the time.

That's before even getting into how civil forfeiture exists as a massively profitable and federally-approved end-run around the Constitution.

I can’t tell if you’re implying fake IDs are something we should try to keep around; I have no problem improving security for underage kids.

Signed, someone who definitely did but shouldn’t have been clubbing at 14.

I am implying that kids will find a way, for those of us that live in the free world and are adults at 18 it is less of a burden. For the poor souls in the US who come of age at 21, fake phones for id might be the new accessory.

Yes, some kids will find a way. I would have. But I have no problem making the barrier to entry higher, at least until parents start responsibly introducing their kids to alcohol or drugs instead of just pretending they don't exist or worse, arguing they are awful from a religious or otherwise zealous perspective.

In a perfect world, parents would teach their kids about how to party responsibly, but we don't live in a perfect world. At the very least, when kids get older they can arguably make slightly better decisions (e.g. think more clearly) sometimes.

Oh I'm sure motivated kids will find hacks and workarounds. If anything it might end up being even easier to fake your age; especially when dealing with businesses that are totally apathetic or unknowledgeable about technology.

Hold someone else's phone?

It would be interesting if the tap just sent over an ID number and then the receiver downloads the data including photo on file.

Typically if presenting in person (such as airport security) you would need to also release your picture, which would show up on the TSA agent's terminal next to a big green checkmark for the valid cryptographic signature.

Without the picture? My understanding is that release does require authentication, and the message could disclose whether that was done with say the fingerprint used when the license was added to the phone.

The use of cryptographic signatures means the weakest link would likely be the identity verification process of the issuing DMV (or their app).

If it's in any way reliant on a central database, or even PGP, I fail to see how you could fake an ID besides finding someone that looks like you and sending that in your place.

That would kinda be the idea, using someone who has a similar looking photo to you. I'm thinking in terms of kids getting into clubs. Physical fake ID's are easy for a knowledgeable bouncer to spot, but if it's all digital data, then it's significantly harder for the bouncer to spot fakes when the data is validated by a system. They'd need entirely new training.

And it's not like there isn't already a black market of stolen IDs already. Get a photo of your client, run it against a database of stolen info, get a match. I understand I'm simplifying this immensely, but if the system can be broken, then it will be exploited. And really it's not if, but when.

I can see this being a useful technology in the case of law enforcement, pharmacies, doctors offices, or anywhere you would need to check in with your driver's license.