Why Everyone Must Be Screened

  • Bruce Schneier
  • Wired
  • October 5, 2006

Why should we waste time at airport security, screening people with U.S. government security clearances? This perfectly reasonable question was asked recently by Robert Poole, director of transportation studies at The Reason Foundation, as he and I were interviewed by WOSU Radio in Ohio.

Poole argued that people with government security clearances, people who are entrusted with U.S. national security secrets, are trusted enough to be allowed through airport security with only a cursory screening. They’ve already gone through background checks, he said, and it would be more efficient to concentrate screening resources on everyone else.

To someone not steeped in security, it makes perfect sense. But it’s a terrible idea, and understanding why teaches us some important security lessons.

The first lesson is that security is a system. Identifying someone’s security clearance is a complicated process. People with clearances don’t have special ID cards, and they can’t just walk into any secured facility. A clearance is held by a particular organization—usually the organization the person works for—and is transferred by a classified message to other organizations when that person travels on official business.

Airport security checkpoints are not set up to receive these clearance messages, so some other system would have to be developed.

Of course, it makes no sense for the cleared person to have his office send a message to every airport he’s visiting, at the time of travel. Far easier is to have a centralized database of people who are cleared. But now you have to build this database. And secure it. And ensure that it’s kept up to date.

Or maybe we can create a new type of ID card: one that identifies people with security clearances. But that also requires a backend database and a card that can’t be forged. And clearances can be revoked at any time, so there needs to be some way of invalidating cards automatically and remotely.

Whatever you do, you need to implement a new set of security procedures at airport security checkpoints to deal with these people. The procedures need to be good enough that people can’t spoof it. Screeners need to be trained. The system needs to be tested.

What starts out as a simple idea—don’t waste time searching people with government security clearances—rapidly becomes a complicated security system with all sorts of new vulnerabilities.

The second lesson is that security is a trade-off. We don’t have infinite dollars to spend on security. We need to choose where to spend our money, and we’re best off if we spend it in ways that give us the most security for our dollar.

Given that very few Americans have security clearances, and that speeding them through security wouldn’t make much of a difference to anyone else standing in line, wouldn’t it be smarter to spend the money elsewhere? Even if you’re just making trade-offs about airport security checkpoints, I would rather take the hundreds of millions of dollars this kind of system could cost and spend it on more security screeners and better training for existing security screeners. We could both speed up the lines and make them more effective.

The third lesson is that security decisions are often based on subjective agenda. My guess is that Poole has a security clearance—he was a member of the Bush-Cheney transition team in 2000—and is annoyed that he is being subjected to the same screening procedures as the other (clearly less trusted) people he is forced to stand in line with. From his perspective, not screening people like him is obvious. But objectively it’s not.

This issue is no different than searching airplane pilots, something that regularly elicits howls of laughter among amateur security watchers. What they don’t realize is that the issue is not whether we should trust pilots, airplane maintenance technicians or people with clearances. The issue is whether we should trust people who are dressed as pilots, wear airplane-maintenance-tech IDs or claim to have clearances.

We have two choices: Either build an infrastructure to verify their claims, or assume that they’re false. And with apologies to pilots, maintenance techs and people with clearances, it’s cheaper, easier and more secure to search you all.

Categories: Airline Travel

Sidebar photo of Bruce Schneier by Joe MacInnis.