Determining the Sequence of Original Ink Writing and Toner Printing

Document examiners are frequently called upon to determine the sequence in which intersecting entries were written. This paper arises from research undertaken to determine the sequence of intersecting original ink writings and toner-printed text. One might intuitively expect that writing over toner would not penetrate the toner. Tests were undertaken based on documents produced on a Hewlett Packard LaserJet printer and a combination of 70 different writing instruments. The subject intersections were prepared to test both sequences of ink before toner and ink after toner. The points of intersection were examined microscopically before and after the removal of the toner. Corresponding intersections for the 2 sequences were compared. It was found that the extent to which the ink penetrated the toner varied between different ink types.