An Introduction to Gel Inks: History and Analysis

With the increasing use and variety of gel pens on the market, forensic document examiners may encounter problems identifying gel pens from other common pen types. This study discusses the initial findings of an investigation into the history, technology, and properties of gel pens. Microscopical (visual) and chemical methods were also evaluated as ways to characterize and identify gel inks. The results of the study demonstrate that the presence of a gel ink can often be determined, but that some gel inks resemble other types of pens, especially roller balls, upon visual examination. Further, chromatographic methods used to characterize traditional dye-based inks may be less useful with gel inks; for these, other spectrometric methods including Raman spectroscopy and energy dispersive x-ray spectrometry (EDS) were evaluated and proved useful. Purchase Article - $10

The Frequency of Occurrence of Handwriting Performance Features Used to Predict Whether Questioned Signatures are Simulated

Forensic Document Examiners (FDEs) examine the physical morphology and performance attributes of a line trace when comparing questioned to specimen handwriting samples for the purpose of determining authorship. Along with spatial features, the elements of execution of the handwriting are thought to provide information as to whether or not a questioned sample is the product of a disguise or simulation process. Line features such as tremor, pen-lifts, blunt beginning and terminating strokes, indicators of relative speed, splicing and touch ups, are subjectively assessed and used in comparisons by FDEs and can contribute to the formation of an opinion as to the validity of a questioned sample of handwriting or signatures. In spite of the routine use of features such as these, there is little information available regarding the relative frequency of occurrence of these features in populations of disguised and simulated samples when compared to a large population of a single individual’s signature. This study describes a survey of the occurrence of these features in 46 disguised signatures, 620 simulated signatures (produced by 31 different amateur forgers) and 177 genuine signatures. It was found that the presence of splices and touch-ups were particularly good predictors of the simulation process and that all line quality parameters were potentially useful contributors in the determination of the authenticity of questioned signatures. Purchase Article - $10

Light and Electron Microscope Approaches to Sequence of Writing Problems

Sequence of writing problems constitute only a small percentage of most document examiners’ case loads, but solving such problems can be crucial. It is important to know the factors that make sequences capable of determination, and when possible, to know how to make such a determination or where to find further assistance. McCrone Associates, a microscopical and microanalytical consulting firm with a wide range of instrumentation and analytical techniques, is occasionally asked to supplement work performed by individual examiners in smaller laboratories. For this reason, McCrone sponsored research to ascertain which instruments, illumination methods, magnifications and techniques might provide more definitive answers to a variety of sequence of writing questions. We derived a number of insights from this research which we would like to present as a general microscopical theory of sequence determinability. It is hoped that this theory will provide the document examiner with one more practical tool with which to approach sequence of writing problems. We also invite our colleagues to test this theory and report both confirmations and discrepancies. Purchase Article - $10

Raman Analysis in Document Examination

Analysis of questioned documents can often be aided by chemical characterization of the ink or toner on the document. In cases where there is little visual difference between reference and questioned areas, Raman analysis can provide chemical information about the pigments and resins which may show similarities or differences in printing materials on the documents.This paper provides background information about Raman spectroscopy, as well as examples of its applicability to the analysis of inks, toners, and pencil leads on documents. Purchase Article - $10

Comparison of Document Examiners' Opinions on Original and Photocopied Signatures

There is a lack of empirical evidence concerning document examiners’ ability to perform handwriting comparisons on photocopied writings. This study aimed to compare the accuracy of examiners’ opinions on 260 original questioned signatures and on the same signatures that had been photocopied. Six of the examiners from the Document Examination Section of the New Zealand Police participated in the study, which comprised two trials. Each trial was constructed according to the accepted process of comparing a group of known (specimen) signatures with a group of questioned signatures where the writer was known to the experimenters but not to the document examiners. One trial contained originals of the specimen and questioned signatures and the other comprised photocopies of the same specimen and questioned signatures. No errors regarding authorship were made for original or photocopied signatures, and there were no instances where an identification/elimination opinion was reversed between a photocopy and its original. Only 2.3% of opinions relating to an original signature differed in any way from that offered for its photocopy. The high correct rates for questioned genuine signatures were similar for original (100%) and photocopied signatures (98%). The correct opinion rate regarding the process of production of original and photocopied, simulated, questioned signatures combined was 99.7%. The results provide evidence that examiners are able to make comparisons on a complex signature with the same accuracy and similar sensitivity when using either originals or photocopies. Purchase Article - $10

Effects of Writing Speed Upon Modes of Signature Simulation: A Kinetic Analysis

To better distinguish between traced and freehand signature simulations, 12 participants practiced upon a WACOM SD420 graphics tablet tracing a historical signature at Slow or Very Slow speeds, with a subsequent comparison of freehand and traced signature simulations. Kinematic analyses focused upon stroke efficiency and pressure, while computer algorithms determined variability of simulations around an original. Traced simulations had reduced spatial variability after practice. Very Slow simulations were more dysfluent, had greater spatial error and employed more pressure. Pen pressures varied more with speed during freehand reproductions. Writing speed was an important contributor to line quality and spatial correspondence during signature simulation. Purchase Article _ $10

Temporal Features of Handwriting: Challenges for Forensic Analysis

This paper looks at handwriting as a multi-stage motor process which develops over time and leaves its time-bound marks in the writing trajectory. It explains some of the time-based research methodology and points out a number of ‘dynamic’ features with potential relevance for forensic application. The final sections of the paper contain suggestions for research leading to the re-establishment of temporal features in the static trace, which could support the handwriting expert’s effort to decide on a document’s authorship and on the circumstances at the time of writing. Some of these suggestions present challenges for prolonged interdisciplinary research co-operation. Purchase Article - $10

Questioned Document Examination Using CEDAR-FOX

Handwriting verification casework often involves comparing the writing in a questioned document with samples of known writing. This paper describes the use of CEDAR-FOX, a software tool for questioned document examination, in a case involving extended writing. The different steps involved from scanning the documents to obtaining a nine-point qualitative measure are described. The various algorithms used, along with a demonstration of its. functionalities on the case are also described. The paper serves two purposes: a guide to using a stateof- the-art software system for a quantitative analysis of handwriting, and an introduction to the science and technology of the software. Purchase Article - $10

Methodological Aspects of Handwriting Identification

Signature authentication and identification of writing or printing is one of the most common issues presented to forensic document examiners. Handwriting is a complex motor skill expressed individually as a result of learned symbols that are stored in long term memory. This paper discusses the stages of memory retrieval that begins the writing process through the muscle joint systems that execute the movements that result in the graphic expression. The authors discuss in detail the identification process and comparison of handwriting characteristics used in the Forensic Science Laboratory, the Netherlands. The process includes discussion of general characteristics, microcharacteristics, spacing characteristics, and variation, as well as touch-ups and disguise. References are made to literature and research projects that support the principles and methodology. The paper concludes with a discussion about the levels of opinions expressed by forensic document examiners.