Problems of Forensic Sciences 2013 Vol. 94 (XCIV) 564-577
RIGHT HAND WRITING VS. LEFT HAND WRITING OF ONE PERSON. A COMPARATIVE STUDY
Tomasz DZIEDZIC
Institute of Forensic Research, Kraków, Poland
Streszczenie
One of the methods of disguising handwriting is to execute it with the unaccustomed hand. The effectiveness of such an attempt may be improved by training the unaccustomed hand to a sufficient degree to eliminate unnatural features from writings executed by this hand. Such handwriting would show both similarities and differences in relation to writing executed with the usual hand. Knowledge about exactly which features are similar or different may improve the effectiveness of detection by forensic handwriting experts of such attempts to disguise handwriting. For the purpose of the present study, the author taught himself to write with his left (unaccustomed) hand, in order to investigate the distribution of similarities and differences between handwriting by different hands. Out of a hundred samples, one half was produced with the left and the other half with the right hand. Every sample in the group written with the left hand matched a right hand sample that had been written on the same day with the same instrument, and consisting of exactly the same piece of text. The results indicated that features which are rooted in the human psychological sphere were similar, while differences occurred mostly among characteristics which depend on the motor skills of the hands.
Słowa kluczowe
Handwriting; Left hand; Unaccustomed hand; Lateralization.