Governments tend to spend money on low-value activities because they do not have market signals or customer feedback to guide them. In this report, I examined the problem with respect to the Transportation Security Administration. As one example, TSA’s SPOT program for finding terrorists spends more than $200 million a year with few if any benefits.

Further confirmation of TSA’s misallocation problem comes from a new academic study looking at the full-body “nudie” scanners installed in U.S. airports at great expense between 2009 and 2013. A team of university researchers bought a Rapiscan Secure 1000 backscatter X-ray machine and began testing it on various types of weapons and explosives. It turns out that a terrorist could fool the machines pretty easily:

We find that the system provides weak protection against adaptive adversaries: It is possible to conceal knives, guns, and explosives from detection by exploiting properties of the device’s backscatter X-ray technology.

If you walked though the machines with a big block of C-4 plastic explosive in your hands, it would be detected. The problem, of course, is that terrorists are smarter than that:

We show that an adaptive adversary, with the ability to refine his techniques based on experiment, can confidently smuggle contraband past the scanner by carefully arranging it on his body, obscuring it with other materials, or properly shaping it. Using these techniques, we are able to hide firearms, knives, plastic explosive simulants, and detonators in our tests. These attacks are surprisingly robust, and they suggest a failure on the part of the Secure 1000’s designers and the TSA to adequately anticipate adaptive attackers.

The Rapiscan machines were pulled from U.S. airports due to concerns about civil liberties and the possible health effects of emitted radiation. But as one of the study authors observed to Bloomberg: “What does this say about how these scanners were tested and acquired in the first place? … It says there’s something wrong with the government’s process … [the process] is secret and not independent. Those are problems.” It’s also a problem that the government has a monopoly on aviation security, and that TSA is not accountable to anyone for its level of efficiency or performance. Well, it’s accountable to Congress I suppose, but that doesn’t really amount to much these days.

The good news is that airport security screening does not have to be a government monopoly. We should move to private contracting with federal oversight, which is the approach taken by Canada and numerous European countries. For more, see my report and check out the writings of Bob Poole at Reason.