Friday, January 6, 2012

Forensic Document Examination (Part I)


"Father and Son", 30"x30", © 1977 Norval Morrisseau;
~ Analysis of the inscription on the reverse side of canvas by Mr. Brian Lindblom - Forensic Document Examiner /Click on image to enlarge/

Forensic document examination – the science today
Author : Dr. Audrey Giles
Date : May 2010

 The scientific examination of documents has been an integral part of forensic science for almost a hundred years and many of the techniques developed over that period are still in use today. However, time does not stand still. The technology used to produce documents continues to evolve; the methods used to produce forgeries are ever more sophisticated; the expectations of lawyers and Courts are yet more demanding.

But forensic science is not sitting on its hands either – advances in techniques and technology mean that the forensic document examiner is fighting back.

What is a forensic document examiner? Who to instruct?

Document examiners are trained scientists. This means that they are trained in scientific method and objectivity, in assessing evidence and drawing conclusions. A good forensic document examiner is expected to hold a University Degree in a basic science – these individuals invest in their training. They have trained alongside forensic scientists and in established forensic science laboratories. They can demonstrate their continued education, having a record of attending meetings, producing research papers and refereeing journals. Very importantly, any forensic document examiner you wish to employ should have invested in equipment and laboratory facilities.

Wrongly, there is a perception that the forensic examination of documents, and particularly handwriting, is something which anybody can carry out on their kitchen table. No – forensic document examination takes place in a properly equipped forensic document laboratory. One group in particular, graphologists, frequently offer their services to the legal profession as forensic handwritings specialists. (These individuals are trained in the pseudo-science of determining personality features from handwriting.) This has absolutely nothing to do with the forensic document examination, and identification of handwritings and signatures as carried out by forensic scientists. Another group who offer services to the legal profession are scientists who have had a long career in official forensic science laboratories who then retire and, without a stick of equipment, reckon to provide the same level of work as they did in their fully equipped forensic document laboratories. They can’t – the science has moved on. No matter how impressive their CV, an invitation to hold a conference at their ‘laboratory’ will quickly clarify their actual working status!

The three main areas of forensic document examination

Actually the main areas of work in this discipline are same as they have been for a long time:

> The identification of individuals through their handwriting.

> Determining whether signatures are genuine or simulations.

> Determining the origin and history of documents.

Handwriting and signatures

The forensic examination of handwritings is very well documented and tested – indeed, the basic principles have been unchanged for many years. It is well established that handwriting is identifiable and everybody’s handwriting consists of a particular combination of character and figure forms which in the mature adult are reproduced unconsciously. However, the particular challenge of handwriting and signature comparisons is that there is a degree of natural variability in everyone’s handwritings and signatures, both from day to day and over the years. While the approach is largely qualitative and subjective, it is no less scientific. And over the last thirty years much effort has been directed into the electronic recognition of handwritings, with some success with the Forensic Information System for Handwriting (FISH) in Germany, the Dutch ‘Script’ system and the Center of Excellence for Document Analysis and Recognition (CEDAR) system in the United States. These electronic processes electronically assess a number of features of the handwriting , for example slope, the area within characters such as ‘o’, spacing and relative proportions; large databases of handwritings have emerged for further research. The majority of these systems are targeted at criminal cases, where examples of handwritings can be collected under very controlled conditions on specialised documents which allow easy collection of the data.

(Course-of-business documents, while providing a more accurate picture of a person’s handwriting at a particular time. are more difficult to evaluate, since the documents involved often include backgrounds which interfere with the collection process.) In addition, in North America forensic scientists have developed a handwriting recognition process which allows large quantities of handwritings to be handled, not so much for the identification of features but for pinpointing useful features for direct comparison.

The basic principles of signature examination were established back in the early twentieth century and it has remained more or less consistent over the years. Signatures are very highly specialised pieces of handwriting and their examination remains very challenging, largely because these are very small pieces of handwriting for comparison. Unlike the situation where an entire page of text is available with hundreds of points of comparison, a small signature provides very much less and it is for this reason in particular that the examination of original signatures rather than copies is so important. The examiner needs to be able to use every feature of the handwriting available. To make life more difficult signatures also demonstrate natural variation. Individuals can be very different in the amount of variation found in their signatures. The degree of variation observed in the signature has to be assessed before any useful comparison can be carried out with a questioned signature. It is essential that sufficient examples of the genuine signature from the relevant time be available in order to determine this range of variation. It is only at that point that the examiner can determine whether the questioned signature falls within or without that range of variation and whether any differences are significant or merely further variation.


To continue reading this article by Dr Audrey Giles who leads the scientific work of The Giles Document Laboratory click HERE.

~ This article is based on a lecture given on 22 January 2010 at the Chancery Bar Association, London.

                 /Wealth Structuring Analysis for Trust and Estate Practitioners/
                 ~ 'Forensic document examination – the science today'

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