Testimony before the U.S. House of Representatives' Select Committee on Homeland Security
There is a serious but reparable vulnerability in the biometric identification system of the US-VISIT Program, which is our last line of defense for keeping terrorists off U.S. soil. A minor software modification that allows the watchlist rule to vary with image quality can increase detection from 53% to 73%. I have provided details to officials who oversee the US-VISIT operations, and this should be implemented as soon as possible. The use of more than 2 fingers for low-quality images can achieve a detection probability of 95%. Although switching from a 2-fingerprint to a 10-fingerprint system may be costly and disruptive, there is no excuse for a 10-billion dollar program to settle for performance below this level. Indeed, our results are not inconsistent with the warning in the November, 2002 NIST report that a 2-finger search was not sufficient for identification from a large watchlist. If slower 2-finger matching algorithms cannot approach 95% detection for poor-quality images, then the US-VISIT Program should be reconfigured with 10-fingerprint scanners as soon as possible.
Our recommendations hinge on the assumption that terrorist organizations as sophisticated as Al Qaeda will eventually attempt to defeat the US-VISIT system by employing terrorists with poor quality fingerprints.