When is a US citizen required to prove it?

Nope, you have to show an appropriate combination of documents to complete an I-9 form. The simplest combination for most people is a driver’s license and unrestricted Social Security card, neither of which is proof of citizenship (though the combination is proof of legal authority to work in the U.S.)

Details on the I-9 form and requirements for documenting US work authorization are here.

Meanwhile, if a police officer confronts you, you are required to give your name and nothing else. You are not required to produce even a driver’s license. Of course, a DL comes in handy if you are pulled over while driving.

Yes, your proof (if you are a citizen) can be a combination of documents that don’t actually prove that you are a citizen. I have that combination (driver’s license and unrestricted SS card) even though I’m not a citizen.

You do, however, if you are a US citizen, “attest, under power of perjury, that [you are] … A citizen of the United States.”

I had to show my birth certificate to get my first driver’s license. Fifteen-year-olds don’t have much in the way of other options to prove their identity.

In fact you don’t need to be a citizen to get a driver’s license. Permanent residents are eligible to get a drivers license also. So it amazes me that anything that relies on citizenship (such as registering to vote) would accept just a drivers license.

I showed my US passport to return to the US from Canada, though I had it ready and handed it to the USCIS officer before he asked, so I can’t really confirm that I HAD to show it, thought it is extremely likely that he would have asked for either a valid US passport, or a valid foreign passport (with visa if necessary). He gave me a cursory interview, declined to search me, and passed me through.

Depends on the state. For states that do not have so-called “stop and identify” statutes, you do not have to provide your name (or anything else) if you are being detained. About half of the US states have such statutes. If you’re being arrested, you may have to give your name and other information, depending on the state.

Both my wife and my daughter got an Ohio driver’s license without having the right to work in the U.S. They had visas which were derivative from my employment visa, so they were entitled to live in the U.S. However, they could not get a Social Security Number (since they couldn’t work), so they couldn’t have presented the right combination of documents to satisfy the requirements of the I-9 form.

And visitors as well, with specific details varying by state. I got a DL from Florida when I was there as a student; getting one from PA would have required 40h of driving lessons for me, but just showing his “back home” license for someone from Germany or France.

Here in MA ; “In addition, you may be asked to provide documents to prove your date of birth, residency, and signature in accordance with RMV policies.”

It appears to be tied to proving your identity rather than your citizenship. I.E. they want to make sure the driver’s license they are going to issue identifies you and not someone else or a fictitous person.

Maybe not that job, but technically if you want any job in the US, employers are required to have you complete an I-9 Form, before they employ you. This document is to be kept in your employement file and substantiates that you have the right to work in the U.S. with proper forms of identification.

In Arizona, as of quite recently, you’ll need to prove your citizenship if (a) you’re stopped by a police officer on suspicion of being an illegal immigrant, or if (b) you want to appear on the state’s ballot as a candidate for President of the United States.

Or both.

My ex was not a citizen (had a green card), but had no problem registering to vote (California). She voted in at least one presidential election that I was aware of, but she claimed she had always voted.

I wouldn’t feel safe making this statement as a general proposition. It’s true in Arizona, which I just had occasion to look up, but other states may have more stringent requirements. Alabama, for example, seems to mandate name and address. Missouri seems to go whole hog: apparently officers with reasonable suspicion may demand that a suspect provide “…name, address, business abroad and whither he is going.”

wrong. you can cough up your social security card and state driver’s license to “pass the I-9”

neither of these things prove citizenship.

false, see my response above.

backpedal. the attestation isn’t the proof.

I would disagree. The OP’s question is “when is a US citizen required to prove it?”

If you are US citizen, the production of a social security card is evidence of his citizenship, as a US citizen could not get one without a birth certificate.

What other ways can a US citizen obtain a social security card?

With a naturalization certificate, possibly in conjunction with a foreign passport?

We had to look into this once for my grandmother…long story. At least in NJ, you don’t need to prove you’re a US citizen to register to vote; you just need to attest that you are. For that matter, I don’t recall being required to show proof of citizenship to register to vote.

It’s actually a big problem for some of my firm’s clients. IL has Motor Voter in effect, and sometimes the Secretary of State’s Office employees kind of gloss over the whole bit about needing to be a US citizen to vote. We’ve had clients who weer not US citizens, but who were not paying careful attention when they applied for driver’s licenses, end up being registered to vote. Which is a problem later on, especailly if they actually do vote.

And if you’re a foreign citizen, then what does the production of a social security provide evidence of? Note just in case you don’t know: legal immigrants get social security cards, too.

Except that permanent resident non-citizens get social security cards which are identical to a citizen’s social security card, so it proves nothing.

you’re basically putting the cart before the horse