Strip and Grope: Offensively Ineffective

By now, readers of this blog are well aware of the new search regime being enacted by the TSA: digital strip searches coupled with “enhanced” pat downs that include fondling of the genitalia. This has prompted more public outcry about the TSA than I have ever witnessed, everything from “If you touch my junk, I’ll have you arrested!” to children being groped to stories of amputees and rape survivors and cancer survivors being repeatedly and horribly embarrassed in public. These new TSA procedures are indisputably an affront to the dignity of every person who is subjected to them. Even Hillary Clinton agrees on that front.

If that weren’t bad enough, the new procedures are ineffective. Dierdre Walker cuts right to heart of the matter with this statement:

We have unintentionally created an agency that now seeks efficiency and compliance more than any weapon or explosive.

Her story goes on to detail her own experience as a traveler whom the TSA believed would be compliant, and their reactions when she was not. She brings her experience as a law enforcement officer to play to assault the effectiveness of the TSA, and her piece is well worth a read. While starting from the same point as Ms. Walker, my line of reasoning ends up in a more loaded charge: The TSA deliberately puts control and intimidation ahead of security.

To back up this charge, let me start with the premise of the new “strip and grope” regime. As stated by the TSA, the procedure came into being after the Christmas underwear bombing plot. The theory, as stated, is that by having a machine that can see through passengers clothing the TSA can effectively prevent a replay of that attack. Those who refuse such machines must be manually searched. So, more correctly, the regime is “strip or grope”.

The problem is that “strip and grope” simply wouldn’t prevent the underwear bomb from getting on a plane again. The underwear bomb was made of PETN, which displays with almost no contrast to flesh on a backscatter X-ray. Looking at the design of the underwear bomb and comparing it to the images of PETN on a backscatter X-ray in this article by Drs. Leon Kaufman and Joseph Carlson leads me to believe that even had a screener looked carefully at the bomb being worn it would not have been detected.

That leads to the next question about the “strip or grope” regime: Does it encourage screeners to look carefully at each image? Consider the following problem already known to exist with X-ray screening of carry-on baggage, as stated by Bruce Schneier:

Airport screeners have a difficult job, primarily because the human brain isn’t naturally adapted to the task. We’re wired for visual pattern matching, and are great at picking out something we know to look for — for example, a lion in a sea of tall grass.

But we’re much less adept at detecting random exceptions in uniform data. Faced with an endless stream of identical objects, the brain quickly concludes that everything is identical and there’s no point in paying attention. By the time the exception comes around, the brain simply doesn’t notice it. This psychological phenomenon isn’t just a problem in airport screening: It’s been identified in inspections of all kinds, and is why casinos move their dealers around so often. The tasks are simply mind-numbing.

It is obvious from the above that having human screeners inspect images of every passenger coming through a TSA checkpoint is exactly the wrong way to implement backscatter X-ray or millimeter wave machines. There are a couple of ways to mitigate this issue from an effectiveness standpoint. First, use the machine only in cases where a specific threat is suspected. Second, use the machine on everyone, but have the computer flag images for further inspection by a human.

Neither of these options, however, gives the TSA the same ability to control and intimidate as using the machines to strip search every traveler. Given that the TSA has put steps in place to address the problem Schneier points out above in the baggage inspection process, it cannot be argued that they should not have known the same problem would exist when having all airline passengers pass through the strip search machines. The TSA knows how to do this in the way that maximizes security, but instead they chose to maximize control over passengers at the expense of security.

Don’t believe me? Let us now look at what happened when passenger Joe Sharkey opted out of the strip search machine at Chicago O’Hare Airport:

“Opt out! We got an opt out!” one bellowed about me in a tone that people in my desert neighborhood in Tucson usually reserve for declaring, “Rattlesnake!”

Other screeners took up the “Opt out!” shout. I was marched from the metal detector lane to one of those nearby whole-body imagers, ordered to take everything out of my pockets, remove my belt and hold my possessions up high. Then I was required to stand still while I received a rough pat-down by a man whose résumé, I suspected, included experience at a state prison.

“Hold your pants up!” he ordered me.

What part of this is TSA procedure and what part of it is over-enthusiastic screeners? We can be sure that the requirement that passengers receive “enhanced” pat-downs that include “meeting resistance” in the groin area are TSA procedure, because they have admitted as much. Additionally, I strongly believe that the public and attention-getting pronouncements when someone requests to opt-out are also TSA procedure since that part of the story is too consistent in incidents across the country. I also expect the TSA, and anyone defending them, to vociferously deny this. Everything else described in Sharkey’s experience I leave to a lack of professionalism displayed by the specifc TSA personnel he encountered.

However, without other screening, the hand searches would have been of questionable benefit of in the underwear bomber case. I personally have never handled PETN and cannot speculate as to what the underwear bomb may have felt like under the bomber’s clothing, so the following is speculation on my part: If the screener doing the hand inspection had stopped simply when resistance was felt in the bomber’s groin area, I doubt the explosive packet would have been detected. The packet was small and fairly flat, and contained in tight-fitting underwear.

More fundamentally, hand screening faces the same problem that the strip search machines do. When doing a high volume of searches, contraband that is not easily differentiated from the smuggler’s body or clothing (such as the underwear bomb above) will more easily evade detection. The only way to address this problem is for screeners to do fewer searches overall and only do searches where a specific threat is suspected.

Objects like knives and guns will easily be found in hand searches, but so will prostheses, insulin pumps, and ostomy bags. Screeners who are searching obviously non-threatening people with serious medical conditions are not searching people who are legitimate threats. As with any use of resources, there is an opportunity cost that must be considered.

By targeting every person who refuses to enter the strip search machine with public attention and a hand search that borders on sexual assault, the TSA is choosing control and intimidation over security.

To put security first, the TSA needs to realize that pre-“strip and grope” security procedures have actually proven effective at preventing terrorists from detonating bombs on aircraft. Yes, terrorists have repeatedly been able to get bomb components on aircraft. But no terrorist flying from a US airport in the past decade has managed to get the components of a bomb on to an aircraft in such a way that they have been successfully detonated. In addition, pre-“strip and grope” security procedures have proven effective in stopping airplane hijackings. When was the last time an aircraft was hijacked in the US? September 11, 2001.

The TSA should be continually evaluating which of their procedures are effectively preventing successful attacks, and pruning away those that aren’t. Instead, they respond by adding ever more restrictions that respond to yesterday’s attack, never considering the costs of what they’re doing. When designing the new restrictions, they put intimidation and control over efficacy.

Nine years after Richard Reid unsuccessfully attempted to take down an airliner with explosives in his shoe, we all must remove our shoes and have them X-rayed even though this has no provable benefit. Four years after a few extremists tried to sneak liquid bombs on to planes, millions of innocent beverages are confiscated every year even though technology exists that can “tell the difference between Pepsi and Coca-Cola“. Finally, and most egregiously, ten months after an al-Qaeda terrorist tried to detonate an underwear bomb, innocent Americans are subjected a search procedure designed to solely to humiliate and intimidate them.