Suspected terrorists have a Constitutional right to ride commercial air travel

Got your attention, didn't I? Now that I've destroyed any possibility of a future career in electoral politics, allow me to explain.

A recent post on Politech notes that the odious "Real ID Act" is poised for passage. Among other things, the Real ID Act establishes a national system of identification, allegedly in order to combat terrorism. You can read the Politech post, which contains a letter from the ACLU's Barry Steinhardt, for all the reasons that this act is a terrible idea. But I had a pretty frustrating email conversation with a friend today, so I want to comment on the amazing notion, which Americans and many others have simply swallowed uncritically, that (1) a unified, pervasive identification system and (2) identity-based travel restrictions are not only permissible but desirable for security purposes.

First, let's talk about permissible. The First Amendment guarantees "the right of the people peaceably to assemble"; it is one of the five fundamental freedoms that the Founders judged of paramount importance, and it is possessed by all people in the United States. This right is given to you by the Bill of Rights, not by an ID card. Even a newborn baby without a name possesses this right, merely by virtue of being a human being under the sovereign power of the United States.

And the freedom of assembly implies freedom to travel, an inference that ought to be trivially obvious from common sense and from past court decisions. You cannot assemble someplace if you're not allowed to travel there. And therefore, you have the right to travel, via airplanes, cars, horses, or your own two feet, without the government's permission.

"But," the sponsors of national ID cards and draconian travel restrictions tell us, "some people cannot be trusted with that freedom, so the government must be empowered to take it away." In particular, say the advocates of "presenting papers", the government must require that no provider of commercial air travel permit passengers to board without presenting government-specified identity documents.

But what is the government allowed to do to a human being under suspicion --- not a convict, not someone under arrest, and not someone caught in the process of committing a crime, but someone under suspicion? Is it allowed to take away fundamental rights? Is it allowed to take away such a person's freedom of speech, or of the press? Is it allowed to force such people to renounce their religion? No, obviously not. The government is allowed to stop a suspect from committing criminal acts, no more and no less, and to punish those duly tried and convicted of crimes.

So, in short, the government is not allowed to prevent a suspected terrorist from exercising his freedom to travel, any more than it is allowed to force a suspected terrorist to renounce his religion. Suspected terrorists have a Constitutional right to ride commercial air travel.

(Of course, they'll need to find an airline that will take them, but the government now makes it illegal for anybody to run such an airline.)

Now, if there were no other way to prevent planes from being hijacked, apart from stopping certain "undesirables" from riding on them, then some restrictions on the freedom of assembly would be permissible. These restrictions would be akin to the classic "shouting fire in a crowded theater" exception for freedom of speech --- that freedom is revoked, in these narrow circumstances, because of the imminent potential for harm, and because no other measure would suffice to prevent such injury.

But it's total, unadulterated nonsense to conclude that infringing on people's freedom to travel is a necessary measure, or even an effective measure, to prevent hijackings. There are four other highly effective measures that, when put together, can protect planes from being hijacked:

• Screen passengers and carry-on baggage for weapons.
• Screen checked baggage for explosives.
• Reinforce cockpit doors, and instruct pilots not to open them under any circumstances.
• Instruct passengers to fight back in the event of a hijacking.

As Bruce Schneier has pointed out, the last two of these are the most important; and none of the four relies on the identity of the passengers. And that's a good thing, because screening procedures are incredibly bad at detecting the intent of a passenger. Until you figure out how to give TSA employees mutant psychic powers, you'd best rely on metal detectors, not data mining.

And what makes us think that a passenger's identity even matters? Would you permit a 92-year-old grandmother to bring an M-16 on board an airplane? Why would it matter whether she's a 92-year-old grandmother or not? Weapons should not be permitted on airplanes, period. Would you leave the cockpit door unlocked if you knew all the passengers fit the FBI's profile of "law-abiding citizens"? Of course not. The cockpit doors should be locked, period. Any security measure that effectively prevents hijackings will work equally well against 92-year-old grandmothers, Girl Scouts, and swarthy young men with odd religious beliefs.

And speaking of effective security measures, let's consider the desirability of a national ID system. "What's the harm?" one might ask. Well, there are plenty of harms, but one of them is that identity theft is on the rise, and encouraging the growth of a centralized ID infrastructure creates a really juicy, inviting target for attack.

Consider the following proposition: "If everybody in the world used Microsoft Windows, then Windows would be more secure." This sentence strikes you all, I hope, as insane. If everybody in the world used Microsoft Windows, then crackers would still break into Windows, and their cracks would just be much more dangerous. In fact, since the value of a crack would be higher, more crackers would try to break into Windows, and there would be more cracks than exist today.

Just so with a national ID system: by establishing a system of interlinked identity databases, you effectively get the sum of the individual databases' vulnerabilities, plus the sum of the databases' value for the potential attacker. It's going to be a freaking bonanza for identity thieves, or for anybody else who wants to commit identity fraud.

Years ago, it was common for banks, colleges, and other institutions to demand your social security number. Therefore, your social security number was effectively a pervasive, centralized identity document, and it was stored in many places, which was perfect for people who wanted to commit fraud of various kinds. Predictably, social security numbers got stolen; fraud and privacy invasions resulted; and the government soon made it illegal for institutions to require disclosure of your social security number.

If I were overhauling the nation's identity infrastructure, I'd learn from the lesson of social security numbers, and go in exactly the opposite direction as current advocates of a single national ID. I would create a compartmentalized, mission-specific ID card system for each legitimate application requiring identity, and make it illegal for identity data to be used for purposes other than those for which they were intended. So, for example, a driver's license would only be treated as proof that you passed the state's requirements for driving; it would be illegal for companies to store your driver's license number in their (large and breathtakingly vulnerable) databases; and even if you faked such a license, it wouldn't get you anything except the ability to drive. Under this system, you'd have a whole suite of identity documents, and none of them would be substitutable for any of the others.

Inconvenient? Sure. Security often entails some loss of convenience or functionality. But if you decided that accurate identification was important to security, that's the sort of system you'd devise, not a single, centralized national ID card.

So, to sum up: national ID cards are a dangerous idea that doesn't increase our security, and in fact actually reduces it in important ways; and preventing people from traveling based on their identities is both unconstitutional and stupid.

On the other hand, a single national ID card system will make it much easier for governments and private-sector database vendors to compile dossiers on every citizen. Granted, these dossiers will frequently be full of errors, but they'll still contain enough information to harass, intimidate, or blackmail you if the holder of that information so desires. So somebody will get some value out of it.