Laplace’s Demon, Santa Claus and TSA’s Secure Flight

No doubt you frequent fliers out there have received emails from your airline of choice talking about TSA’s Secure Flight. As you make air travel reservations in the future, your airline will communicate with TSA to get, essentially, a fly/no-fly decision from the Secure Flight system. As the TSA explains in the “How it works” section of their website dedicated to Secure Flight:

Secure Flight matches the name, date of birth and gender information for each passenger against government watch lists to:

  • Identify known and suspected terrorists
  • Prevent individuals on the No Fly List from boarding an aircraft
  • Identify individuals on the Selectee List for enhanced screening
  • Facilitate passenger air travel
  • Protect individuals’ privacy

After matching passenger information against government watch lists, Secure Flight transmits the matching results back to aircraft operators.

Did you notice the extreme use of irony there? Secure Flight is used to “facilitate passenger air travel” and yet Secure Flight’s sole purpose is to keep people off of planes. (I think someone at the TSA doesn’t know what facilitate means.) Irony aside, Secure Flight is ignorant of (or at least tone-deaf to) the US’ strong social and legal tradition of freedom of movement.  Secure Flight can act as a preemptive refusal of air travel in the absence of due process, which contravenes citizens’ freedom of movement.

Let’s talk about Pierre-Simon Laplace for a second. The French mathematician and astronomer described “an intellect” so vast that it knew the location and momentum of every atom in the universe. With this knowledge, this intellect (latter dubbed Laplace’s Demon by biographers) could know the future. As he wrote:

We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.

So with two attributes, location and momentum, Laplace’s Demon can know the future. With gender and birthday (along with name), Secure Flight can know bad guys from good guys and keep them off a plane.

The problem is that neither work. Laplace’s Demon has been slain multiple times. Secure Flight and the No-Fly List have and will continue to suffer the same fate.

Nations (UK, Israel, the US) and Agencies (DHS), like malevolent Santa Clauses, are building multiple mother-of-all naughty-and-nice lists. Their slavish devotion to Laplace’s Demon fuels their hopes that by knowing everyone’s name (and other attributes) they somehow can predict (and in some cases, prevent) the future. Hubris and ignorance are the twin attributes of such plans and neither ought to have a place in the programs of civil societies.