Examination of Firearms Review: 2007 to 2010 - Interpol

14. Miscellaneous
In this part we decided to deal with two different aspects: the first one is the emergence
of new technologies in the field of printing techniques, the second one is more linked to
the use of new technologies to identify printers.
Regarding the new technologies dedicated to produce documents, the striking one is the
recent appearance of Computer To Plate (CTP) inkjet for offset press which was
presented during the DRUPA forum of 2008. This method allows production of offset
plates thanks to an inkjet process. At the end, the printed document looks under
magnification like an inkjet document although it is an offset one. If this kind of novelty
isn’t a problem for identifying false or authentic document by comparison it may be a
great problem for identifying the technique used and the level of the fraud (especially for
banknotes or security documents). A similar issue, is the appearance of the inkjet press
with millions of nozzles, for the moment in white and black, but likely evolving in colour.
The issue of authenticating precisely the origin of a document has always existed.
Digital technologies can now allow this, by linking a document to its printer or scanner.
Chiang, Khanna, Mikkilineni and al [211], [216] made interesting reviews of the existing
techniques to embed information in the printing at the digital document level or at the
printer mechanism level. Although these techniques are not widely disseminated, it is of
use to at least know of their existence and detect their presence, since they can give
accurate information for investigators. The forensic part of the “Non Impact Printing
Conference” often deals with this kind of matter. It is a proactive way to know what could
be the track and trace solutions for tomorrow.
15. Challenges
The document examination expert now has at his disposal an array of techniques,
complementary but requiring widened competencies (chemistry, printing processes,
image analysis, electronic for security documents, statistics and probabilistic…). Thus
for a document examiner to remain efficient it is becoming necessary to move towards
the specialists skills of data and signal processing, whilst remaining informed of the
developments in the technologies of printing, the fast progress of which makes the work
increasingly difficult. Possessing all these competencies in the single field of document
examination is becoming almost impossible. So a way to allow general improvement of
the methods is to integrate a questioned document facility inside a laboratory, where all
the required activities are already undertaken (electronic, signal and image analysis…)
16. Ackowledgement
We would like to acknowledge, Raymond Marquis (UNIL), Isabelle Montani (UNIL), Wil
Fagel (NFI), Laurent Köhler (INCC), Laetitia Heudt (ULg/INCC) and Meredith Miller
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