TSA's website page requires an expiration date to be on any ID before they will accept it as valid. (Though to be honest the page doesn't actually say that the card can only be used pre-expiration.)

Features of identification documents that make alteration or forgeries more difficult improve with time. I.D. cards are "lost" then "found" by someone who resembles the original holder.

If we don't have these documents expire, we'd still be using outdated technology, and it would be far easier for someone to use one that was created for someone else.

Also, please keep in mind that best we can tell from what little information TSA provides, presentation of documentation of your identity (i.e., "showing ID") is not a requirement, only an option that will allow you past the checkpoint with a less-thorough search or without the requirement that you participate in an interrogation intended to determine your identity.

Following [EDIT: updated 2010-05-09] is what I've been able to find out about TSA's policies regarding airline passenger identification:

What are the rules concerning airline passenger identification by TSA?

Although TSA refuses to publish all the rules they require passengers to follow at airport checkpoints, from what we can distill from TSA press releases, heavily-redacted information obtained via FOIA requests, TSA blog posts, and other information they publish on the Web, it's relatively clear that your boarding pass is all the documentation that's ever required for domestic flights. It seems that passengers are not required to present documentation of their identities to TSA staff, and that doing so is not a condition of crossing the TSA checkpoint.

TSA won't publish the rules we're supposed to follow. So what do we know about their I.D. policies?

According to a 2008 press release from TSA, TSA's airport passenger identification policy changed on June 21, 2008, but "showing I.D." was seemingly not required before and is seemingly not required now.

Prior to June 21, 2008

Before June 21, 2008, the situation seemed to be: In order to proceed to the "secure area" of an airport after being stopped at a TSA barricade, each passenger must submit to a pat-down and search for metallic objects using a hand-held metal detector, along with a hand-searching of any carry-on baggage, unless he presents documentation of his identity (i.e., unless he "shows I.D."), in which case he must submit only to a search for metallic objects on his person via walk-through metal detector and search of any carry-on baggage using an X-ray machine.

In other words: back then, showing I.D. simply got you a less-thorough search than you'd otherwise receive.

Now

Beginning June 21, 2008, the situation seems to be: Each passenger still has the option of showing I.D. and participating in the less-thorough searches (walk-through metal detector and X-raying of carry-ons), but the alternative now involves not only being thoroughly searched for dangerous items, but also identifying oneself verbally and participating in an interrogation intended to verify one's identity (via phone call from Homeland Security headquarters). Chillingly, it seems from the aforementioned TSA press release that this alternative also requires that someone be "cooperative with officers". What that cooperation entails is not defined.

Initial reports from TSA indicated that while people who claimed that their government-issued I.D. card was misplaced or stolen would be allowed to take the alternate route through the checkpoint (with the questioning), those who willfully refused to show their papers would be barred from proceeding. It's unclear whether or not this is still the case, or if it was ever the case, as TSA's initial press release seems, based on information received from TSA via Freedom of Information Act request, to have been inaccurate.

Summary of present situation and how to exploit it

In short, best we can tell, complying with TSA's "papers, please!" request is not necessary in order to fly domestically, it's simply a way to avoid the hassle of a thorough search for dangerous items, the hassle of providing convincing information in support of your claim to be who you say you are, and having to cooperate with TSA airport staff in any manner they see fit.

This is a great system for people who wish to do harm in airports or on airplanes, since getting a falsified identification document (i.e., a "fake I.D.") is relatively simple, and presentation of one almost guarantees that TSA staff will look at someone with less scrutiny, making it easier for him to take weapons, explosives, or incendiaries past the security checkpoint. Even if TSA could detect such fraud with perfect accuracy, using the Carnival Booth Algorithm, terrorists can probe an identity-based security system like TSA's by sending a number of people on harmless trips through the system, noting who is flagged for extra searches and who isn't. Then they can send those who aren't flagged -- people who almost certainly will get through security with a less-thorough search -- on terrorist missions.

Why does TSA want to identify us? What's wrong with them doing so?

This isn't about your safety. It's about control -- a few people's control over the rest of us.

The primary reason that TSA wants to know who you are is their desire to restrict people's movement based on Homeland Security blacklists. As did every government that has imposed totalitarian rules, TSA repeatedly tells us that their freedom-restricting policies are about safety, security, and rooting out subversives. Of course, this policy is really about extra-judicial punishment, allowing our executive branch of government to sidestep our judicial branch and punish someone for any reason or no reason at all. That's not the way things are supposed to work in the United States. It's ripe for abuse, and it's an infringement on our freedom.

For more on showing I.D. in the general sense, please see the Identity Project's "What's Wrong With Showing I.D.?" page.

Previous discussion on FlyerTalk

For more on TSA airport I.D. policies, see also the following FT threads (the fifth of which is what brought me to FlyerTalk for the first time; I'm the subject of that April 8, 2008, article on the front page of the Kansas City Star):

• 2007-02-19: No ID Passenger threatened by police at DCA
• 2007-03-27: DCA Lawyer responds: You must show ID
• 2007-09-07: Legal Advice, forced to show ID (6 months ago)
• 2007-09-06: Your right to fly without ID (proof at last)
• 2008-04-08: Article:No ID needed to board plane
• 2008-05-01: new info from TSA re: airlines requesting ID
• 2008-05-01: does the law/courts say ID is not required to...
• 2008-06-06: Starting June 21: Refuse to Show ID, No Entry to Sterile Area
• 2008-06-09: Actually, it looks like you can still fly without ID
• 2008-06-11: TSA blog addresses the new airport ID rule
• 2008-06-20: TSA says new airport ID rule is not about control
• 2008-06-22: No ID - Reports from the Field
• 2008-06-23: Forget ID after 6/21: expect invasive ?s including political affiliation
• 2008-06-24: ACLU Blasts TSA's Political Party ID check questions
• 2008-11-19: Are you kidding me: No ID
• 2009-05-01: What is the ID Policy?
• 2009-05-27: TSA SOP re: airport ID requirements provided to IDP via FOIA request
• 2009-07-20: Flying with expired license
• 2009-07-28: Do kids with seats (age 2-10) need ID?
• 2009-08-04: Expired Drivers licence + Temporary One -Can I fly?
• 2009-08-10: Has anyone had a problem without photo ID at the gate of Jetblue at JFK and MCO?
• 2009-10-30: How many times do I show my BP and ID at the checkpoint?
• 2009-11-09: Can I travel with my expired drivers license as ID?
• 2009-11-16: Flyer “Processed” (Arrested?) in NM After Declining to Show ID
• 2009-11-21: What happens if an ID is lost?
• 2009-11-22: No longer using passport as ID for TSA - here's why
• 2009-11-28: Expired ID
• 2009-11-30: Damaged NY State License
• 2009-12-08: Flying with expired id or no id
• 2009-12-20: College ID or Expired License for Check-in ID
• 2010-01-29: Great Safety Screening at EWR!!!
• 2010-02-04: Passport card not accepted by TSA yesterday
• 2010-02-06: Getting selected anyway, should I refuse to show ID?
• 2010-02-15: Flying Without ID & TSA @ SFO
• 2010-02-18: TSA requires Passport on Intl Flights?
• 2010-03-29: Can I travel with my expired drivers license as ID?
• 2010-04-11: ID required for unaccompanied minor?
• 2010-04-12: Question about using a DL at a checkpoint
• 2010-04-12: Costco card as ID

Exactly. And I've pointed out here on FT that therefor there's no requirement per the written policy statement that an id be unexpired to be acceptable, and the only response has been the internet equivalent of being looked at like I was crazy. And I've also asked why, if the id must indeed be unexpired to be valid, the TSA's written statement doesn't just say so by using the words "unexpired" or "currently valid" in the statement, and I've gotten the same response.

hey andy i am heading out to san diego tomorrow from denver. my id has expired 8 months ago. i am heading back to renew it. will they let me through security? i thought i would ask. and who do i call before i make a fool of myself

u stated in anouther thread its been 10 months. it can be expired up to a year which is twelve................even then they cannot stop u from flying, they just look down your pants

Read three posts back for a description of TSA policies. I pay fairly close attention to this issue, and as stated above, best I (and I think most people) can tell, there is no requirement that you present any documentation other than your boarding pass in order to get past a TSA airport barricade. Doing so just allows you through with less scrutiny. As long as you're not carrying any weapons, explosives, or incendiaries, you should be fine. If you want to sneak any of those through, you're going to be way better off if you show some documentation of your identity.

I guess one is better off presenting an ID at a checkpoint if one wishes to bring contraband through the checkpoint; what irony!