NCJ Number
139768
Journal
Journal of Forensic Sciences Volume: 37 Issue: 6 Dated: (November 1992) Pages: 1600-1609
Date Published
1992
Length
10 pages
Annotation
This article reports on a study that examined facsimile copies of documents prepared with various writing instruments to determine how accurately they reflected the original, and facsimile copies of altered documents were examined to determine if evidence of the alteration could be seen on the facsimile copy.
Abstract
Five printing processes of facsimile machines were used for comparison to the original documents. The study found that image quality was affected by the type of printing process of the fax machine, resolution setting, halftone and contrast setting, and the amount of telephone-line interference during a fax transmission. Alterations, traced signatures, pen pressure, and type of writing instrument were difficult to detect. Tremor that was observed on the fax copy could have been the result of a traced forgery, or it could have been the result of telephone-line interference. Pictorially, all the fax machines captured an image from the original; however, the copies lost the subtle characteristics required for an accurate document examination. Good line quality that reflects speed, variation of pen pressure, pen lifts, and presence of tapered strokes were not always reproduced on the fax copy. The laser printer reproduced a pictorially perfect document and "cleaned up" distortions or extraneous marks. Consequently, the examiner is not given the opportunity to examine the document with all of its imperfections and identifiable characteristics. 6 figures and 3 references