taunt the police and community from afar.
Investigators analyzed the ink, because it seemed to be blood or a bloodlike simulation. Modern ink can be one of four basic types: iron salts in a suspension of gallic acid, with dyes; carbon particles suspended in gum arabic; synthetic dyes with a range of polymers and acids; and synthetic dyes or pigments in a range of solvents and additives. The questioned ink is tested through a highly technical process called microspectrophotometry, to determine the absorption spectrum, or through thin-layer chromatography, to reveal the exact chemical composition. It can then be compared on a precise level to the database of ink profiles at most central investigative agencies. Yet the ink in these letters was unusual. If it was actual blood or a blood mixture, technicians could do a serological analysis to obtain the blood type and the more individualizing protein profiles. However, the writing fluid turned out to be neither blood nor ink. It was turpentine-thinned paint, such as might be used in a print shop. That discovery helped to narrow leads, although not in a way that was useful just then.
The next item to examine would be the type of paper used, and the paper on which the letters had been written proved to be somewhat ordinary, so that analysis offered no clues. It would help only if the same type of paper was found in the killer’s possession or at his workplace. Paper is classified by the materials in its composition, differing according to additives, watermarks, and surface treatments. Specialists can determine the date when a particular type of paper was introduced on the market. Paper was considered to be generic rather than unique evidence, so it proved nothing outside the context of other pieces of evidence, but taken with other circumstances, it could help support a case.
While sophisticated equipment is used for special tests, the basic tools for comparing a questioned document with a known exemplar (we know that this person scripted this piece of writing) are a magnifying lens, microscope, camera with filters, and good lighting. Since the letter writer had not used a typewriter or printer, identification via distinct machine signatures was irrelevant.
The handwriting style of these red-lettered notes was certainly individualizing, as well as cryptic, but investigators knew they would need a suspect and samples of his handwriting before they could fully exploit it. They also had experts examine the content of the notes, which suggested the author’s seemingly angry frame of mind. There appeared to be no codes or cryptic references, and content analysis, which utilizes reading sources that match phrasing, had not yet been developed as an investigative tool at the time of this case. Even if it had, there was too little content available from these brief communications to do a thorough evaluation. The police knew they would have to wait for more such letters before they could develop proper leads, but getting more notes meant that someone else might also die. They did not use graphology—the extrapolation of personality traits from handwriting—because contrary to popular belief, it is not a science.
Handwriting experts study writing samples to try to determine if two (or more) documents were written by the same person and thereby to identify the known author of one sample with the unknown author of a similar one. The same odd characteristics are expected to show up across samples originating with the same person—even when he tries to disguise his writing. Analysts look at both class characteristics, which derive from the general writing system learned, and individual characteristics, which are specific to the way a person’s distinctive handwriting style develops. It’s the latter that plays the most important part in forensic investigation. The best exemplars will contain some of the same words or phrases as the questioned document, and thus some of the same ways of
Investigators analyzed the ink, because it seemed to be blood or a bloodlike simulation. Modern ink can be one of four basic types: iron salts in a suspension of gallic acid, with dyes; carbon particles suspended in gum arabic; synthetic dyes with a range of polymers and acids; and synthetic dyes or pigments in a range of solvents and additives. The questioned ink is tested through a highly technical process called microspectrophotometry, to determine the absorption spectrum, or through thin-layer chromatography, to reveal the exact chemical composition. It can then be compared on a precise level to the database of ink profiles at most central investigative agencies. Yet the ink in these letters was unusual. If it was actual blood or a blood mixture, technicians could do a serological analysis to obtain the blood type and the more individualizing protein profiles. However, the writing fluid turned out to be neither blood nor ink. It was turpentine-thinned paint, such as might be used in a print shop. That discovery helped to narrow leads, although not in a way that was useful just then.
The next item to examine would be the type of paper used, and the paper on which the letters had been written proved to be somewhat ordinary, so that analysis offered no clues. It would help only if the same type of paper was found in the killer’s possession or at his workplace. Paper is classified by the materials in its composition, differing according to additives, watermarks, and surface treatments. Specialists can determine the date when a particular type of paper was introduced on the market. Paper was considered to be generic rather than unique evidence, so it proved nothing outside the context of other pieces of evidence, but taken with other circumstances, it could help support a case.
While sophisticated equipment is used for special tests, the basic tools for comparing a questioned document with a known exemplar (we know that this person scripted this piece of writing) are a magnifying lens, microscope, camera with filters, and good lighting. Since the letter writer had not used a typewriter or printer, identification via distinct machine signatures was irrelevant.
The handwriting style of these red-lettered notes was certainly individualizing, as well as cryptic, but investigators knew they would need a suspect and samples of his handwriting before they could fully exploit it. They also had experts examine the content of the notes, which suggested the author’s seemingly angry frame of mind. There appeared to be no codes or cryptic references, and content analysis, which utilizes reading sources that match phrasing, had not yet been developed as an investigative tool at the time of this case. Even if it had, there was too little content available from these brief communications to do a thorough evaluation. The police knew they would have to wait for more such letters before they could develop proper leads, but getting more notes meant that someone else might also die. They did not use graphology—the extrapolation of personality traits from handwriting—because contrary to popular belief, it is not a science.
Handwriting experts study writing samples to try to determine if two (or more) documents were written by the same person and thereby to identify the known author of one sample with the unknown author of a similar one. The same odd characteristics are expected to show up across samples originating with the same person—even when he tries to disguise his writing. Analysts look at both class characteristics, which derive from the general writing system learned, and individual characteristics, which are specific to the way a person’s distinctive handwriting style develops. It’s the latter that plays the most important part in forensic investigation. The best exemplars will contain some of the same words or phrases as the questioned document, and thus some of the same ways of
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