Profiling systems like CAPSS are based on abstract data--computer records, not direct obersvation and knowledge. Knowing this, someone trying to penetrate the system need only leave the right "paper" trail (we need a new term in the computer age--"byte trail"?) to fool the system. The system's a machine--garbage in, garbage out. No room for intuitation, experience, or true insight into human nature. This is a lazy solution.

Another implication of systems like this is that a person must have a byte trail to be allowed by the government to engage in certain activities. The systems would necessarily flag as suspicious people who don't have enough data to allow the system's algorithms to work. Suppose you don't believe in credit and thus don't have any data in your credit report? Suspicious. Don't drive and thus have no driving record (one input to CAPS)? Suspicious.

Profiling systems don't exist in a vacuum--their effect on your ability to participate in society feeds back in a way to subtly nudge people in the direction of conformity. These systems punish noncomformity by making it harder to use essential services such as transportation.

The MIT paper was very interesting. They explain the Achilles Heel of automated profiling so clearly that it's intuitively obvious why random searches are superior: Terrorists don't even have to know the algorithm, they simply have to test the system empirically to find out which of their members get a low (safe) score, and send those people on missions.

The September 11th hijackers apparently did exactly that when they took a number of test flights in advance of their attack.

Ben Franklin said "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." And now the brains at MIT have provided a rigorous scientific proof that old Ben knew what he was talking about. We lose both liberty and security when the government starts trying to monitor our behaviors and beliefs. If something makes no sense, on the face of it, ask who benefits. In this case, a government intent on asserting greater control over its citizenry benefits from wrongheaded initiatives like CAPS.