The impersonality of machines can also filter out racism. Five years ago, the ACLU objected to body scans because they were administered selectively, "based on profiles that are racially discriminatory." But the best way to remove selection bias is to scan everyone. In Phoenix, TSA has put the backscatter monitors in a sealed room 50 feet from the security checkpoint, so the officers who staff them can't see you. All they can see are X-ray images, which capture density, not pigment. To them, everyone is the same color.
Putting a machine interface between you and the examining officer protects your visual as well as tactile privacy. In a strip search, the officer sees you exactly as you are. On a monitor, the image can be filtered. The "privacy algorithm" doesn't obscure every detail of your physique, as pictures on TSA's Web site make all too clear. But that's not essential. Look closely at the pictures. It's not the body that has been rendered indistinct. It's the face.
That's the first key to reconciling airport screening with privacy: We need to see your body, not your face. For those 30 seconds, we know where you are. If your scan suggests a problem, we'll pull you aside. The second key is that the officer who sees you on the monitor never sees you in the flesh. In Phoenix, TSA hasn't just put the monitors in a separate room. It's laying cables to put them in an entirely different terminal. Likewise, the officer who sees you in the flesh never sees you on the monitor. It's like the blind men and the elephant: Nobody has the whole picture.
Which brings us back to Susan Hallowell. The Times twice avoided naming the naked woman in its Feb. 24 photo. It did, however, mention that the machines were made by AS&E. On AS&E's Web site, I found a press release complaining that pictures circulating in the press were obsolete because they'd been taken in 2003. Then I ran across a 2004 article that said Hallowell had demonstrated the technology the previous year. I typed her name into a search engine and up came a 2003 wire story with a photo of her, fully clothed, next to a monitor showing the same image that appeared in the Times. I didn't need to read a word. You could tell she was the same woman just by looking at her face.
Hallowell volunteered for this notoriety. But what happened to her mustn't happen to others. In the age of body scans, privacy means keeping your name, your face, and your nude image apart. That job doesn't end at the security gate; it begins there. Will your scan leak? "Images will not be printed, stored or transmitted," TSA swears on its Web site. Directly above that assurance, the agency has posted four nude pictures—"actual images shown to the Transportation Security Officer during the backscatter process." And you thought airport screeners had no sense of humor.
Enough with the fairy tales. We lost our innocence when the planes hit the towers. Now we're losing our modesty. If we're going to be ogled, at least protect us from being Googled.
A version of this article also appears in the Outlook section of the Sunday Washington Post.