TSADoes Profile, But Very Ineffectively, Math Study Demonstrates
WASHINGTON, D.C. (June 1, 2015): A new internal investigation by the Transportation Security Administration (TSA) shows that its own airport screening process fails about 95% of the time, so the need to improve its current terrorist profiling techniques is glaring, says mathematician and public interest law professor John Banzhaf, who notes that a mathematical study showing how to make terrorist profiling substantially more effective in protecting the public has been largely ignored.
So called Red Teams, posing as passengers, found that TSA checkpoints failed 67 out of 70 times to detect mock explosives or banned weapons, according to a recent Homeland Security Inspector General’s report, so the need to more effectively select high risk passengers for a more thorough inspection is obvious, says Banzhaf.
But, although the TSA has been found to have used several screening programs – including behavioral profiling, often called “chat downs’ – none are even marginally effective, he says.
But TSA terrorist profiling would be far more effective, and create fare fewer security risks, if the profiling included several criteria which are perfectly legal, and if it were done in accordance with what mathematics shows is the best way, claims John Banzhaf.
Fortunately, there is a well established mathematics of selection and testing which is used thousands of times every day to detect everything from rare genetic disorders to manufacturing defects on an assembly line, says Banzhaf, a mathematician who created a statistical tool called the “Banzhaf Index.”
Not surprisingly, it is based in large part on TSA concentrating searches where one is most likely to find a problem, rather than ineffectively treating all subjects equally or slashing security in many situations based on age or gender, but ignoring ethnicity, religion, and national origin.
TSA’s terrorist screening
Terrorist screening is clearly effective, says Banzhaf, noting other areas where targeted screening is commonly used. Screening for Tay-Sacks disease is concentrated on Jews, and for sickle-cell anemia on African Americans.
Screening for breast cancer is concentrated on older women, even though younger women – and even a few men – may have the disease. Similarly, products with a higher history of defects will be selected more often on the assembly line for examination than those with a lower probability of having faults.
Applied to situations like TSA airport screening for terrorists, a detailed mathematical study shows that treating all passengers equally – and selecting elderly Asian females and toddlers for secondary screening no more frequently than young Muslim males – is illogical as well as inefficient in stopping terrorist attacks.
Moreover, relaxing security for women, even those who as young Muslims present a much higher risk than most other passengers, or letting older Arabs escape strict scrutiny when younger Asian males are more strictly searched, make no sense whatsoever, suggests Banzhaf.
Instead, the mathematical TSA study shows that certain groups known to present a statistically higher risk than others should be selected for heightened pre-boarding screening more frequently – a frequency determined not just by age and gender, but also by ethnicity, religion, and national origin. In this way, scarce resources are most effectively concentrated where the greatest chance of a problem lies.
Previously, the TSA has refused to even consider openly using this logical and established technique – even though it reportedly has used it indirectly and therefore less efficiently – because of wide spread beliefs that it is unconstitutional or unfair to people in higher risk groups, says Banzhaf.
But the U.S. Supreme Court has ruled that factors such as race and ethnicity – much less religion, gender and age – can be used in making selections, provided that it serves a compelling governmental interest, and that it is not the only factor used. That’s why state universities may constitutionally consider race and ethnicity in their admissions process, notes Banzhaf, suggesting that preventing fatal terrorist attacks is an even more compelling governmental interest than increasing racial diversity in classrooms.
Even the Justice Department has proclaimed that, while factors like race cannot ever be used in criminal investigations by the TSA unless there is a clearly identified individual suspect of that race, race and similar factors may constitutionally be considered in protecting homeland security and preventing terrorist attacks, even if there is no specific suspect, provided only that it is not the only criteria considered.
In the case of terrorists, Banzhaf suggests, these other criteria might include dress (e.g., wearing bulky or heavy clothing in warm weather), carrying a backpack, behavior (e.g., nervousness or inappropriate sweating, absence of eye contact, pacing, etc.), as well as age or gender. In short, a young Muslim male who is nervous and also carrying a backpack may constitutionally be given greater scrutiny, and/or kept off PreCheck lanes more frequently, than a calm elderly Asian female carrying a small purse.
If members of groups with a higher risk potential were singled out more frequently for secondary screening, everyone would benefit, including even members of those very groups. We would be more likely to stop potential terrorists and at a far lower cost, and even innocent young Muslim males would benefit because lines – and the waiting time on them – would be much shorter for everyone (including for young Muslim males) because of the inspection time now being spent on most low risk passengers.
After all, says Banzhaf, it’s the total time spent on undergoing security procedures which is the most important concern for most passengers after their safety, and this time delay would be reduced for everyone using a system employing heightened screening based in part on criteria like religion and ethnicity, as well as sex, and age.
Everyone is concerned about not being blown up, and also about not missing their plane because of inspection delays. Concentrating inspections on those most likely to be involved in complex terrorists conspiracies would benefit the great majority of young Muslim males who are law abiding, since it would increase their chances of not dying, and also of not missing their flight due to security delays.
“If I could be assured of a substantially greater probability that airline bombers would be detected – and also that waiting time on long lines would be significantly reduced – if only I agreed that people in my category be subject to a longer and more intense search process, I would gladly agree,” says Banzhaf.
“As the GAO has now shown, the TSA has adopted procedures which have little scientific validity, and apparently waste billions of taxpayer dollars while causing unnecessary delays and providing only marginally increased security. Perhaps it’s time to at least experiment with something with a solid basis in science, and a proven record in the real world of testing and inspections,” suggests Prof. Banzhaf.
JOHN F. BANZHAF III, B.S.E.E., J.D., Sc.D.
Professor of Public Interest Law
George Washington University Law School,
FAMRI Dr. William Cahan Distinguished Professor,
Fellow, World Technology Network,
Founder, Action on Smoking and Health (ASH)
2000 H Street, NW
Washington, DC 20052, USA
(202) 994-7229 // (703) 527-8418
http://banzhaf.net/ @profbanzhaf
