NCJ Number
150470
Journal
Journal of the Canadian Society of Forensic Science Volume: 27 Issue: 2 Dated: (June 1994) Pages: 59-67
Date Published
1994
Length
9 pages
Annotation
This paper illustrates the association of a typewriting system component, namely the correction lift-off tape, with residual carbon film within the text of a questioned typewritten document.
Abstract
For the purposes of this research, two correctable carbon film ribbon systems were used. A Ko-Rec-Type carbon film ribbon and NU-KOTE lift-off correction tape were installed in an IBM Correcting Selectric typewriter, and an Easystrike High Yield Correctable Ribbon and Easystrike lift-off tape were installed in an IBM Wheelwriter word processor. Text was produced and corrected on regular bond paper. The ribbon and lift-off tape were removed from the typewriters for microscopic examination and photography. The process of physical matching involved the analysis, comparison, and evaluation of class and individual characteristics. The first step was to establish correspondence of class features. The examiner must confirm that the corrected character is consistent with carbon film ribbon production. The process continues with the comparison of the corrected character on the document with the associated character on the correction tape. Since it is difficult to view both subjects at the same time with a stereomicroscope, photomicrographic transparencies of each character should be produced and the transparencies superimposed and compared. The random fracture outline resulting from incomplete removal of a carbon film character provides the basis for the physical matching of the carbon film residue and the lift-off correction tape. Physical matching by superimposition of photographic transparencies is an effective and preferred method of comparison and demonstration. 7 figures and 4 references