Biometrics: The body and soul of security

Bertillonage in-disguise?

Way back in 1879, a French police clerk by the name of Alphonse Bertillon suggested that individual homo sapiens could be precisely identified through carefully gathered measurements of different parts of the body.

Using an impressive array of calliper-compasses the Bertillonage systems recorded height, arm span, cranial diameter, forehead tilt, as well as the length of the right ear, left foot, left forearm and selected fingers. It also called for an examination of the size and shape of his nose, and a thorough recording of any skin blemishes or scars.

Such dimensions and descriptions were duly noted and filed away with information regarding the individual's past misdemeanours.

Eventually the procedure was cutdown to a simple mug shot, with a quick physical description alongside a set of fingerprints.

Fingerprints satisfy what Dunstone describes as the two main features required for a biometric to be useful for identification purposes: stability and distinctiveness.

"You can take biometric measurements from just about any part of the body, but to be a reliable form of identification it must be stable over time and differ between individuals," Dunstone said.

One of the first countries to adopt and refine the system was Argentina. Police administrative officer Juan Vucetich widely implemented and evangelised the practice of keeping records of fingerprints. By 1892, Francisca Rojas became the first person to be convicted of murder based on fingerprint evidence gathered at the scene of the crime.

However, fingerprint-based identification was quickly becoming a victim of its own success. When the Mona Lisa went missing in 1911, fingerprint-identification implicated Vicenzo Perrigia. The tell-tail thumbprint he left on the glass of the famous painting was, however, of no use in locating him, due to the chaotic filing system French authorities had been using since they began collecting prints almost 20 years before.

As security agencies around the world began implementing mandatory fingerprinting of convicted criminals, these databases swelled to mass proportions. By 1956 the FBI had 141 million prints on file, and the race was on to provide accurate searching and storage facilities via the emerging field of computing.

Two decades later the Argentine police were using a system called Digicom, to track down so-called dissidents in the streets of Buenos Aires. Combining digital processing, with radio technology the system scanned in fingerprints and relayed the information from the police cars back to a central database.

"They would stop you in the street and ask for your national identity card," explains Oscar Lima, an Argentine who emigrated to Australia in the 90's. "The card had your photo on the front, and a complete set of fingerprints on the back. You would have to wait while the fingerprints were scanned into the machine and relayed back to the base."

The Digicom system enabled the Videla government to keep tabs on Argentina's population, thirty thousand of which "disappeared" between 1976 and 1981.

Across the world, biometric information--gathered since Bertillonage systems came into broader use at the turn of the century--was being digitalised, stored and accessed via computers. The results of its implementation, however, were based largely on the governmental agenda behind them.

By 1985, Australia finally caught up with advances in the rest of the world and began to digitalise its fingerprint databases.

Superintendent Alan Snow, who has since retired, was charged with overseeing the implementation of a system developed by Rockwell Automation, but integrated by NEC.

"We had to make the choice between a system that basically counted the ridges of each finger print and converted it into some kind of number, and one which compared the images, so we went with the latter," Snow explained. "We collected the fingerprints as we always had, then put them through the scanner."

The system took a group of Japanese technicians about 12 months to implement, and radically reduced the amount of work required to cross-check fingerprints with those on the databases.

While the nature of the data gathered has changed significantly, and the power to access databases has improved along with technological advances, the core idea is the same.

Biometrics was born of Bertillon's attempts to compile specific and unique physical measurements, and use these to identify individuals and track their activities.