Should we use iris images for positive identification?

A new report by biometric researchers at the National Institute of Standards and Technology (NIST) used data from thousands of frequent travelers enrolled in an iris recognition program to determine that no consistent change occurs in the distinguishing texture of their irises for at least a decade.
The new study counters a previous study of 217 subjects over a three-year period that found that recognition of the subjects’ irises became increasingly difficult, consistent with an aging effect.*
To learn more, NIST biometric researchers used several methods to evaluate iris stability.
Researchers first examined anonymous data from millions of transactions from NEXUS, a joint Canadian and American program used by frequent travelers to move quickly across the Canadian border.
As part of NEXUS, members’ irises are enrolled into the system with an iris camera and their irises are scanned and matched to system files when they travel across the border.
NIST researchers also examined a larger, but less well-controlled set of anonymous statistics collected over a six-year period.