Forensic Expertise Area : Questioned Document and Printer Examination & Forensic Trace Element Analysis
There are several optical and chemical techniques available to compare inks. Within the NFI the Laser Ablation Inductively Coupled Plasma Mass Spectrometer (LA-ICP-MS) is frequently used for this purpose. This technique is fast, does not require any sample preparation, and the discriminative power is high.
Ideally, the outcome of the LA-ICP-MS analysis needs to be evaluated against the ‘background’ variation of Known Comparisons of reference material: both Known Matches (KM, within variation) and Known Non Matches (KNM, between variation). This reference material needs to be representative for the relevant population of inks.
Currently we do not have a good representation of this ‘background’ variation. The goal of this research project is to determine this ‘background’ variation that can be used in the evaluation of casework analyses to obtain the Likelihood Ratio. Inks which are involved are ballpoint pen inks and inkjet printer inks.
Institute/Company : NFI
Digital Technology and Biometrics / Microtraces
|Country :||The Netherlands|
Koen Herlaar / Wim Wiarda