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Poster Sessions Presented at the International Symposium on Setting Quality Standards for the Forensic Community: Part 3 (Forensic Science Communications, July 1999)


October 1999 - Volume 1 - Number 3

Poster Sessions
Presented at the
2nd International Symposium on the
Forensic Examination of Questioned Documents
Albany, New York
June 14 – 18, 1999

Part 3

The following abstracts of the poster sessions are ordered alphabetically by authors’ last names.

Advances in Document Examination:
The Video Spectral Comparator 2000
J. H. Taylor and G. M. Mokrzycki
Federal Bureau of Investigation
Washington, DC

The purpose of this presentation is to introduce Foster and Freeman’s (Worcestershire, United Kingdom) VSC2000 (video spectral comparator) to the forensic community, explain how it functions, and how it can be used for document examination. By utilizing a color and a black-and-white video camera, filters, and variable light sources with a desktop computer using Windows software, the VSC2000 allows its user to analyze inks, visualize hidden security features, and reveal alterations of documents.

The VSC2000 is capable of capturing images in ultraviolet, visible, and infrared wavelengths and can, therefore, be used to reveal the interaction of light on different materials. These interactions, imaged on the computer screen, enable the user to

  • Reveal information beneath ink obliterations.
  • Sort shredded paper through differences in luminescent intensities.
  • Detect matching fibers across torn or cut edges.
  • Visualize faded inks.

Images captured by the VSC2000’s computer can be rotated, flipped, and rendered negative so that they are easier to read. The computer is also capable of storing and mixing different images thereby enabling distinct images to be overlaid or compared side by side. These digital images can be saved allowing duplication of analysis, printing, or attaching to an e-mail.

Although using variable light sources and filters are not new techniques in document examination, the VSC2000’s computer-assisted examinations allow the user to try numerous lighting and filter options more quickly than with conventional photography, thereby speeding analysis. 

Genuine Signature: Fraudulent Document
G. J. Throckmorton
Salt Lake City Police Department
Salt Lake City, Utah

A typewritten document was presented to a local bank authorizing the transfer of funds from the savings account of an elderly woman into the savings account of her grandson’s girlfriend. Shortly after the transfer was completed, the girlfriend withdrew the money, closed out the account, and left the area.

Two to three weeks later, the elderly woman received her monthly bank statement and was surprised to note a significant withdrawal had been made from her account. She inquired of the bank, and they produced the typed document which authorized the transfer of funds. The questioned letter had a signed name which clearly resembled the signature of the woman. The victim was quite old and was uncertain if she actually signed the document, but she could not remember doing it.

The document was submitted to the Laboratory for a signature examination. A comparison between the questioned signature and several known signatures of the victim determined that all were done by the victim. However, during the examination, a faint line of discoloration was observed that went horizontal across the paper, slightly above the signature. Ultraviolet and video spectral comparator examinations could find no reason for this line, and there were no other indications of alteration.

One teaspoon of Drano crystals was dissolved in eight ounces of water to make a solution that was sprayed in a fine mist upon the paper. This resulted in an instantaneous materialization of hidden writing on the upper portion of the paper. The writing remained visible for about two to three minutes but then disappeared. Retreatment of the paper caused the writing to become visible a second time, but it disappeared again. When the document was treated a third time, the hidden writing became visible again, and photographs were taken before the writing disappeared. The handprinted message said, “Gone for three days leave newspaper next door,” and below the handprinted message was the signature of the victim.

Known exemplars were obtained from the suspect and submitted for comparison. The handprinted portion of the note, originally written in disappearing ink, was of common authorship with the known writing exemplars.

The follow-up investigation confirmed the suspect had prepared a handwritten note using a disappearing-type ink and had the victim sign it. This note was supposed to be given to the newspaper delivery person, but it was not. A portion of the paper, above the victim’s signature, was soaked in water which caused the ink to dissolve and disappear from the paper. This soaking caused a horizontal line that was only visible using oblique lighting techniques. Once the ink from the handprinted portion was removed, the suspect had a blank document that contained only the genuine signature of the victim.

After making several photocopies of the paper containing the victim’s genuine signature, the suspect practiced until she was able to type the authorization letter around the genuine signature of the victim.

Although various examination techniques were utilized, there was no indication of the hidden writing until it was sprayed with the Drano solution. Crystal Drano (Drackett Products Company, Cincinnati, Ohio) was used in this examination because a weak base solution was needed to make the ink visible and because it was easy to obtain.

The Drano solution is a weak base solution which will frequently make hidden writing visible when used on certain types of disappearing ink. This examination of the document confirmed the victim’s story and determined that the questioned signature was genuine, but the document was fraudulent. 

Eradication Of Impression Evidence: Part 1
T. W. Welch

Michigan State Police
East Lansing, Michigan

Impression evidence can be an extremely valuable piece of evidence concerning fact-finding issues in document examination. These impressions can provide the basis for truth, deceit, and identification. Without latent impressions, the truth of these issues may never be known or identified.

If someone fraudulently signed his or her name on top of another document and later received knowledge that there might be impression evidence that could incriminate, could he or she eradicate any possible impressions left behind? And if so, would there be any evidence to support such a finding? The purpose of this experiment, therefore, was to determine if impression evidence can be eradicated by means of rubbing with the hand and to determine if there was any evidence to suggest that someone attempted to eradicate these impressions. In addition, an effort was made to determine if different writing instruments had an effect on the ability to eradicate impression evidence.

The implementation of this experiment included the selection of a test group.

Individuals within this test group were asked to eradicate impressions in a packet of documents to which they had placed their signatures while using different writing instruments. The attempt at eradication was noted by the part of the hand used and the amount of time spent rubbing the impression. The documents were then processed utilizing the ESDA. The data was compiled and placed into five categories. These categories included the following:

  • The signature name.
  • The time, in minutes and seconds.
  • The area of hand used.
  • If the impressions were eradicated.
  • If there was evidence of eradication.

After compiling the data, nothing could be said about the effect of the type of writing instrument used on those documents which did not reveal any impressions after an attempt to eradicate was made. However, 30 of the 40 documents revealed impressions observed with side lighting. Of the ten documents which failed to reveal impressions using side lighting, nine were written with a Sharpie Permanent Marker-Ultra Fine. With respect to the eradication of the impressions, 85 percent of the documents examined contained evidence suggesting that there was an attempt to eradicate the impressions. Therefore, and for the purposes of this experiment, the results suggest that it is possible to eradicate impression evidence by rubbing with the hand. It also suggests that as a result of this action, there may be evidence supporting that an attempt was made to eradicate these impressions. 

Preparing Research Articles for Publication in Forensic Science Journals
J. M. Winchester
Florida Department of Law Enforcement
Tallahassee, Florida


Recent court cases emphasize the need for research and scientific findings published in peer-reviewed journals. The research article should follow a specific formatting style; contain illustrations, charts, or graphs; and list accurate references.

Methods and Materials

The forensic document examiner conducts research in order to replicate current procedures and to describe new scientific findings. Detailed research results are suitable for publication in scientific journals.

The researcher should adhere to the preferred format for writing the research. Information concerning the preferred format is found in the Instructions for Authors section of journals. Information about the Journal of the American Society of Questioned Document Examiners may be found on the Internet at www.ASQDE.org.

Research articles usually include an abstract, an introduction, methods and materials, results, a discussion, and references. Articles should also include illustrations, charts, and graphs with labels and captions. A ruler should be included in photographs and the citation of magnification noted. Quoted books and articles should be attributed. References must be accurate and listed alphabetically at the end of the article. The researcher must take responsibility for authenticity of the research.


The properly prepared research paper may be submitted to a scientific journal. The advantage of sending the research paper to a peer-reviewed journal provides the author and the public the assurance that the paper was reviewed by two or more peers familiar with the scientific area. Reviewers are governed by the agreement of confidentiality and are free from any conflicts of interest. The publication of research provides a valuable resource for the forensic science discipline.


There is a need for increased scientific research and the publication of the findings. Additional research in the field of questioned documents will provide a valuable source of information important to the criminal justice system. 

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