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Forensic Iris: A Review, 2022



James Matey, George W. Quinn, Patrick J. Grother


John Daugman correctly summarized the state of forensic iris recognition circa 2006 for the book Forensic Human Identification: an Introduction [1]: Iris recognition has limited forensic value, because (unlike fingerprints or DNA, for example) (1) iris patterns are not left behind at crime scenes; (2) and in death the pupil usually dilates significantly, the cornea clouds, and the iris tissue degrades relatively rapidly. (3)Moreover, currently available iris databases are quite small (only a few million digitized samples of iris patterns exist today); and because of the novelty of this biometric, (4) such data currently has no legal or established forensic status as admissible evidence. [Numbers() added.] In the intervening 15 years, all of Daugman's observations, save one, have been over taken by events: (1) The advent of ubiquitous high resolution video/photography has led to widespread collection/retention/dissemination of imagery of sufficient resolution for iris recognition. (2) Demonstrations of post-mortem iris recognition have been made. (3) Large iris databases have been constructed. The legal issue (4) remains to be resolved. Forensic iris was a topic at the June 2018 Iris Experts Group Meeting. Key issues discussed there were: measurements and analysis that needs to be done to provide the underpinnings for a resolution of the legal and forensic status of iris recognition and the development of documentation for such measurements and analysis that will enable explanation of iris collection and recognition to lay audiences, including those in a courtroom. An important point was that the perceptions of the public with respect to biometrics and iris recognition in particular, largely formed by the popular media, are frequently inaccurate and must be considered. To help resolve the questions discussed at that meeting, this paper reviews the current state of the art in iris recognition, the perceptions of the public regarding iris recognition, and the me
Technical Note (NIST TN) - 2226
Report Number


biometric recognition, forensics, iris recognition.


Matey, J. , Quinn, G. and Grother, P. (2022), Forensic Iris: A Review, 2022, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 16, 2024)


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Created July 18, 2022, Updated February 29, 2024