Dusting for fingerprints and tracking digital footprints

Abstract

In January of 2010 Dubai security consultants ran a series of image-sequences captured by CCTV and phone calls through advanced computer algorithms to connect a trail of digital dots which confirmed that senior Hamas military leader Mahmoud al-Mabhouh had not died not of natural causes in his hotel suite but was assassinated by a large team of covert operatives. A new category of image-analysis has emerged which is generally referred to as “walk-back technology”. Walk-back is a recombinant technology that works primarily with advanced facial recognition software and biometrics in combination with data-tracking to identify and plot the movement trajectories of multiple entities within differentiated spaces over time, their points of crossover, convergence and dispersion in order to play back and schematise a set of actions in relation to a chain of events.

Notes

1 The Bertillonage method of “judicial photography” was the most widely accepted (see Jäger).

2 Translation of Locard's discussion of the exchange principle by Kirk (4).

3 It must be noted that fingerprints, although widely accepted as unique identifiers, have yet to be systematically studied as empirical evidence. The ear-print is regarded as a more singular attribute of individuality.

4 These include spatial information, for example GPS coordinates; other forms of spectral analysis such as infrared; the movement trajectories of subjects through space; the acoustic register of radio frequencies and voiceprints; and especially the realm of virtual data from emails, internet search histories, cellular communication, swipe cards, barcode scans and blue-tooth enabled devices. Clarification of walk-back technology (as presented on the CBC programme The Current, 16 March 2010) was provided by Dr. Thomas Heseltine, Biometrics Consultant at Aurora Computer Services in an interview I conducted with him on 20 December 2011.

5 While 3D face recognition is still much less used than 2D face recognition or other biometrics, commercial systems became available around 2003–04 and large-scale examples of its use came about in 2005.

6 From infrared satellites that map the subsurface of the earth, magnetic resonance imaging (MRI) directed towards medical diagnostics, to the use of ground penetrating radar (GPR) in geophysics, none of these systems employ visible light to harvest information and generate detailed pictures of physical matter.

7 Thanks to Dr. Thomas Heseltine for “walking” me through some of the technical aspects of face-recognition software, which are briefly sketched out here in this text. See also his PhD dissertation “Face Recognition”, as well as several published articles.

8 See the “Forensic Architecture” report on the death of Palestinian demonstrator Bassem Abu Rahma during an April 2009 West Bank protest produced for the human rights organisation B'Tselem. In a single frame of video the trajectory of the tear gas grenade that killed him is visible thus confirming (through the application of video-to-space analysis) the illegality of the angle at which he was shot and serving to re-open a case against the IDF that had been closed. http://www.forensic-architecture.org/investigations/bassem-abu-rahma/