Another Look at Handwriting Movement

Forensic document examiners usually observe and assess line quality in the written stroke without direct knowledge of the kinematics of the writing instrument used to produce it. Features in handwriting relating to line quality such as speed or pen pressure variation have been described since the days of Osborn. Qualitative assessment of such features by document examiners is routine and made according to well documented principles. In this pilot study, a digitizing tablet with an inking pen was used to measure the movement of a writing instrument as a time series of data points. Handwriting from 15 subjects was obtained using a limited passage of cursive text, basic handwriting movements, and handprinted text. Traditional examiner evaluation of select features was compared to dynamically measured data produced by the writing tablet. The study suggests that this type of handwriting measurement system can be used to test various theoretical aspects relating to both handwriting movement itself and to the examination of that handwriting by document examiners. More specifically, the study demonstrates a new and effective method for the validation of examiners’ abilities regarding the “subjective” assessment of dynamic writing characteristics from a static written record.