A Forensic Study on Sequence of Strokes in Laser Printed Document and Stamp Pad Impressions

Abstract

The analysis of overlapping of different ink strokes has always been an important factor in forensic document examination, as seen in cases of fraud and tampering of documents.
The objective of this study is to use microscopy to analyse the sequence of strokes of laser printer toner and stamp pad inks and evaluate its potential in identifying various characteristics that are found at the intersections. Samples prepared with different printer, ink brands and paper types, were examined by making two types of stroke intersections. At these intersections, features such as gloss variation, gaps in strokes, surface morphology and stroke narrowing were observed.
This study contributes in establishing that despite variations in paper, ink and toner, microscopy can be a reliable technique for the determination of sequence of strokes in laser printer toner and stamp pad inks. With the existing studies mainly focusing on the use of more sophisticated analyses, this study shows the importance of the use of stereomicroscopy on its own as a non-destructive and easily available method for stroke sequence determination. It is an adaptable and dependable method that can be effectively applied across laboratory setups with varying levels of technical infrastructure