Typewriter and Typewriting Examinations


Although modern computer printers have, almost exclusively, replaced the traditional typewriter, still on occasion typewritten anonymous notes, threatening letters, extortion requests, and altered contracts are the active portion of a questioned document case. While typewriters are often thought of a single piece of equipment, many machines are often a combination of machine, type-element, and single or multiple-pass ribbon. This genre of machine may be more appropriately referred to as a “typewriting system.” While each major component may enjoy it’s own identifying characteristics, the possibility of interchanging components between similar models normally renders the possibility of identifying a specific typewriting system to a suspect typewritten letter a rather remote prospect. In cases where a computer and printer are involved, the identification process is so remote as to be almost non-existent. Many times, for instance, the ability to even distinguish between a laser printer, photocopier, scanner, and facsimile machine cannot be reliably accomplished. In fact, many multipurpose machines that encompass all four processes are in common use in today’s office environment. Their output is essentially the same.

Evidence Submission

In the case of typewritten material, such as a typewritten letter, the original of the questioned document is almost a basic necessity. Machine copied documents are usually unsuitable for a typeprint examination except where differences in type font are obvious. Opinions derived from such documents, if any, are generally much less definitive.
Occasionally, a specific suspect machine is to be submitted to the laboratory. If the typewriter is not serviceable, no attempts should be made to effect repairs. Care should be taken during transportation so as to not damage, or further damage, the typewriter.

The submission of any suspect typewriter is the best standard for the document examiner, however there may be occasions when this is not practical. If this is the case, the submitter can place a clean sheet of paper in the suspect machine(s) and type the material in question. Obviously, if the questioned letter is several pages long, it may not be possible to type all of it. Likewise, if the questioned material is only a few lines, it may be necessary to type it several times.

Typewriting and Typewriter Examinations

At times, the identification of a typewriter make and model from a questioned typewritten document, that is, “What make of typewriter was used to type this letter?”, can be accomplished. The typewritten material in question is first classified then searched through reference files. Highly definitive opinions are rare due to the limitations of the reference files and the many “newer” typewriters that filled the corporate space between approximately 1962 and the advent and introduction of the computer printer, and associated software, that became available for public consumption in the 1980’s. Generally speaking, the older the machine, the greater the chance of identification.

Other typewriting examinations consist of visual and microscopic comparison of questioned typewriting and standard typewriting in an attempt to identify a typewritten document to a specific machine. Individual characteristics that include type alignment, spacing, broken or damaged type font, ink density, and pressure are considered. As discussed in the introduction, it has been found that comparisons involving documents typed on later model element machines and computer printers are rarely definitive.

While generally a lengthy process, the examination of one-pass plastic (carbon) ribbons can also be undertaken to determine if the questioned text is present. During the production of a typewritten document on a machine employing such a ribbon, the carbon film image of each letter or punctuation mark is transferred to the document leaving a letter-shaped void in the ribbon. These voids can easily be read (although backward). This process does not work on older typewriters using fabric ribbons.

Rev 06/19

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