HOME

TheInfoList



OR:

In forensic science, questioned document examination (QDE) is the examination of
document A document is a written, drawn, presented, or memorialized representation of thought, often the manifestation of non-fictional, as well as fictional, content. The word originates from the Latin ''Documentum'', which denotes a "teaching" o ...
s potentially disputed in a court of law. Its primary purpose is to provide evidence about a suspicious or questionable document using scientific processes and methods. Evidence might include alterations, the chain of possession, damage to the document, forgery, origin, authenticity, or other questions that come up when a document is challenged in court.


Overviews

Many QDE involve a comparison of the questioned document, or components of the document, to a set of known standards. The most common type of examination involves handwriting wherein the examiner tries to address concerns about potential authorship. A document examiner is often asked to determine if a questioned item originated from the same source as the known item(s), then present their opinion on the matter in court as an expert witness. Other common tasks include determining what has happened to a document, determining when a document was produced, or deciphering information on the document that has been obscured, obliterated, or erased. The discipline is known by many names including 'forensic document examination', 'document examination', ' diplomatics', 'handwriting examination', or sometimes 'handwriting analysis', although the latter term is not often used as it may be confused with
graphology Graphology is the analysis of handwriting with attempt to determine someone's personality traits. No scientific evidence exists to support graphology, and it is generally considered a pseudoscience or scientifically questionable practice. How ...
. Likewise a forensic document examiner (FDE) is not to be confused with a graphologist, and vice versa. Many FDEs receive extensive training in all of the aspects of the discipline. As a result, they are competent to address a wide variety of questions about document evidence. However, this "broad specialization" approach has not been universally adopted. In some locales, a clear distinction is made between the terms 'forensic document examiner' and a 'forensic handwriting expert/examiner'. In such cases, the former term refers to examiners who focus on non-handwriting examination types while the latter refers to those trained exclusively to do handwriting examinations. Even in places where the more general meaning is common, such as North America or Australia, there are many individuals who have specialized training only in relatively limited areas. As the terminology varies from jurisdiction to jurisdiction, it is important to clarify the meaning of the title used by any individual professing to be a "forensic document examiner".


Scope of document examination

A forensic document examiner is intimately linked to the legal system as a forensic scientist. Forensic science is the application of
science Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence ...
to address issues under consideration in the legal system. FDEs examine items (documents) that form part of a
case Case or CASE may refer to: Containers * Case (goods), a package of related merchandise * Cartridge case or casing, a firearm cartridge component * Bookcase, a piece of furniture used to store books * Briefcase or attaché case, a narrow box to ca ...
that may or may not come before a
court A court is any person or institution, often as a government institution, with the authority to adjudicate legal disputes between parties and carry out the administration of justice in civil, criminal, and administrative matters in acco ...
of law. Common criminal charges involved in a document examination case fall into the " white-collar crime" category. These include
identity theft Identity theft occurs when someone uses another person's personal identifying information, like their name, identifying number, or credit card number, without their permission, to commit fraud or other crimes. The term ''identity theft'' was c ...
, forgery, counterfeiting, fraud, or uttering a forged document. Questioned documents are often important in other contexts simply because documents are used in so many contexts and for so many purposes. For example, a person may commit murder and forge a suicide note. This is an example where a document is produced directly as a fundamental part of a crime. More often a questioned document is simply the by-product of normal day-to-day business or personal activities. The American Society for Testing and Materials, International (ASTM) publishes standards for many methods and procedures used by FDEs. E30.02 was the ASTM subcommittee for Questioned Documents. These guides were under the jurisdiction of ASTM Committee E30 on Forensic Sciences and the direct responsibility of Subcommittee E30.02 on Questioned Documents. The ASTM Questioned Document Section has been disbanded. All of the Standards are now available through SWGDOC (The Scientific Working Group for Document Examiners). The Standard Guide for Scope of Work of Forensic Document Examiners indicates there are four components to the work of a forensic document examiner. It states that an examiner "makes scientific examinations, comparisons, and analyses of documents to: # establish genuineness or nongenuineness, or to expose forgery, or to reveal alterations, additions or deletions; # identify or eliminate persons as the source of handwriting; # identify or eliminate the source of typewriting or other impression, marks, or relative evidence; and # write reports or give testimony, when needed, to aid the users of the examiner's services in understanding the examiner's findings." Some FDEs limit their work to the examination and comparison of handwriting; most inspect and examine the whole document in accordance with this ASTM standard.


Types of document examined

Documents feature prominently in all manner of business and personal affairs. Almost any type of document may become disputed in an investigation or litigation. For example, a questioned document may be a sheet of paper bearing handwriting or mechanically-produced text such as a ransom note, a forged cheque, or a business contract. It may be material not normally thought of as a 'document'. FDEs define the word "document" in a very broad sense as being any material bearing marks, signs, or symbols intended to convey a message or meaning to someone. This encompasses traditional paper documents but also includes things like graffiti on a wall, stamp impressions on meat products, or covert markings hidden in a written letter, among others.


Historical cases

* The Alger Hiss perjury appeal where the "fake typewriter hypothesis" saw expert
Martin Tytell Martin Kenneth Tytell (December 20, 1913 – September 11, 2008) was an expert in manual typewriters described by '' The New York Times'' as having an "unmatched knowledge of typewriters". The postal service would deliver to his store lette ...
recreate a perfect replica typewriter (1952) * The Panama Papers case in which false documents were provided to the Supreme Court of Pakistan (2017) * The National Archives forgeries (aka Martin Allen forgeries or
Himmler Heinrich Luitpold Himmler (; 7 October 1900 – 23 May 1945) was of the (Protection Squadron; SS), and a leading member of the Nazi Party of Germany. Himmler was one of the most powerful men in Nazi Germany and a main architect of th ...
forged documents) (2005) * The Killian memos (2004) * The ImClone / Martha Stewart trial (2004) * The
Yellowcake Forgery The Niger uranium forgeries were forged documents initially released in 2001 by SISMI (the former military intelligence agency of Italy), which seem to depict an attempt made by Saddam Hussein in Iraq to purchase yellowcake uranium powder from ...
(2003) * The Nina Wang case of the Teddy Wang wills (2002 and 2010) * The anthrax attack mailings on the US Senate (2001) * The JonBenét Ramsey murder (1996) * The Paul Jennings Hill murders (1994) * The Hitler Diaries printed by the magazine ''Stern'' and determined to be forgeries (1983) * The
Mark Hofmann Mark William Hofmann (born December 7, 1954) is an American counterfeiting, counterfeiter, forgery, forger, and convicted murderer. Widely regarded as one of the most accomplished forgers in history, Hofmann is especially noted for his creatio ...
forgeries and murders (1980–84) * The Mormon Will that Melvin Dummar claimed left him part of
Howard Hughes Howard Robard Hughes Jr. (December 24, 1905 – April 5, 1976) was an American business magnate, record-setting pilot, engineer, film producer, and philanthropist, known during his lifetime as one of the most influential and richest people in t ...
' fortune (1978) * The Clifford Irving claim that
Howard Hughes Howard Robard Hughes Jr. (December 24, 1905 – April 5, 1976) was an American business magnate, record-setting pilot, engineer, film producer, and philanthropist, known during his lifetime as one of the most influential and richest people in t ...
authorized his biography (1972) * The Zodiac Killer (1969) * The Lindbergh kidnapping (1934) where comparison of the ransom note and
Bruno Hauptmann Bruno Richard Hauptmann (November 26, 1899 – April 3, 1936) was a German-born carpenter who was convicted of the abduction and murder of the 20-month-old son of aviator Charles Lindbergh and his wife Anne Morrow Lindbergh. The Lindbergh kidnap ...
's handwriting, by expert Albert S. Osborn, was crucial * The
Adolf Beck case The Adolf Beck case was a notorious incident of wrongful conviction by mistaken identity, brought about by unreliable methods of identification, erroneous eyewitness testimony, and a rush to convict the accused. As one of the best known causes ...
s (1896 and 1904) where handwriting expert Thomas H. Gurrin repeated an erroneous identification * The
James Reavis James Addison Reavis (May 10, 1843November 27, 1914), later using the name James Addison Peralta-Reavis, the so-called Baron of Arizona, was an American forger and fraudster. He is best known in association with the Peralta land grant, also kno ...
(
Baron of Arizona James Addison Reavis (May 10, 1843November 27, 1914), later using the name James Addison Peralta-Reavis, the so-called Baron of Arizona, was an American forger and fraudster. He is best known in association with the Peralta land grant, also kn ...
) land swindle trial about forged documents involved in a Spanish barony and land grant (1895) * The
Dreyfus Affair The Dreyfus affair (french: affaire Dreyfus, ) was a political scandal that divided the French Third Republic from 1894 until its resolution in 1906. "L'Affaire", as it is known in French, has come to symbolise modern injustice in the Francop ...
(1894), involving non-FDE
Alphonse Bertillon Alphonse Bertillon (; 22 April 1853 – 13 February 1914) was a French police officer and biometrics researcher who applied the anthropological technique of anthropometry to law enforcement creating an identification system based on physical me ...
, although professional comparisons exonerating Dreyfus were ignored * The Howland will forgery trial (1868) * Operation Bernhard, a secret
Nazi Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in ...
plan to destabilize the British economy through counterfeited banknotes (1939) * Active measures, a
Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...
-era political warfare program, led by the KGB, including the spreading of disinformation using falsified documents Although the crimes were committed before the discipline of document examination was firmly established, the letters of the Jack the Ripper case have since been examined in great detail.


Candidacy

A person who desires to enter a career of forensic document examination must possess certain traits and abilities. The ASTM Standard E2388-05ASTM International
These guides are under the jurisdiction of ASTM Committee E30 on Forensic Sciences and the direct responsibility of Subcommittee E30.02 on Questioned Documents. Copies of ASTM Standards can be obtained directly from ASTM International.
(Standard Guide for Minimum Training Requirements for Forensic Document Examiners) lists several requirements for the "Trainee Candidate". First and foremost, "an earned
baccalaureate degree A bachelor's degree (from Middle Latin ''baccalaureus'') or baccalaureate (from Modern Latin ''baccalaureatus'') is an undergraduate academic degree awarded by colleges and universities upon completion of a course of study lasting three to six ...
or equivalent from an accredited college or university" is required as it gives the aspirant a scientific background with which to approach the work in an objective manner, as well as bestowing necessary biological,
physical Physical may refer to: * Physical examination, a regular overall check-up with a doctor * ''Physical'' (Olivia Newton-John album), 1981 ** "Physical" (Olivia Newton-John song) * ''Physical'' (Gabe Gurnsey album) * "Physical" (Alcazar song) (2004) * ...
, and chemical
knowledge Knowledge can be defined as awareness of facts or as practical skills, and may also refer to familiarity with objects or situations. Knowledge of facts, also called propositional knowledge, is often defined as true belief that is distin ...
sometimes called upon in the work. Second, excellent eyesight is required to see fine details that are otherwise inconspicuous. To this end, the aspirant must successfully complete: * a form discrimination test to ensure that the aspirant is able to tell apart two similar-appearing yet different items, * a
color perception Color vision, a feature of visual perception, is an ability to perceive differences between light composed of different wavelengths (i.e., different spectral power distributions) independently of light intensity. Color perception is a part of t ...
test, and * near and distant visual acuity tests "with best corrected vision within six months prior to commencement of training." Beyond the above, additional desirable skills include knowledge of paper, ink, printing processes, or handwriting.


Training

There are three possible methods of instruction for an aspiring document examiner: # Self-education is the way the pioneers of the field began, as there was no other method of instruction. #
Apprenticeship Apprenticeship is a system for training a new generation of practitioners of a trade or profession with on-the-job training and often some accompanying study (classroom work and reading). Apprenticeships can also enable practitioners to gain a ...
has become the widespread way many examiners are now taught. This is the method that is recommended by
ASTM ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, an ...
in Standard E2388-05. To conform with the ASTM standard such training "shall be the equivalent of a minimum of 24 months full-time training under the supervision of a principal trainer" and "the training program shall be successfully completed in a period not to exceed four years". The training program must also include an extensive list of specific syllabus topics outlined in ASTM Standard E2388-05. #
College A college (Latin: ''collegium'') is an educational institution or a constituent part of one. A college may be a degree-awarding tertiary educational institution, a part of a collegiate or federal university, an institution offerin ...
and
university A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United Stat ...
programs are very limited. This is due, in part, to the relatively limited demand for forensic document examiners. It also relates to the need for extensive practical experience, particularly with respect to handwriting examination. It is difficult to include this degree of practical experience in a normal academic program. There are some distance learning courses available as well. These are taught through a virtual reality classroom and may include an apprenticeship program, a correspondence course, or both. A trainee must learn how to present evidence before the court in clear, forceful testimony. Fledgling examiners in the later stages of training can get a glimpse into the legal process as well as a better sense of this aspect of their work through participation in a mock trial or by attending court hearings to observe the testimony of qualified examiners. These are guidelines and not requirements.


Examination


Examination types

Examinations and comparisons conducted by document examiners can be diverse and may involve any of the following: * Handwriting (
cursive Cursive (also known as script, among other names) is any style of penmanship in which characters are written joined in a flowing manner, generally for the purpose of making writing faster, in contrast to block letters. It varies in functionali ...
/
printing Printing is a process for mass reproducing text and images using a master form or template. The earliest non-paper products involving printing include cylinder seals and objects such as the Cyrus Cylinder and the Cylinders of Nabonidus. The ...
) and
signature A signature (; from la, signare, "to sign") is a Handwriting, handwritten (and often Stylization, stylized) depiction of someone's name, nickname, or even a simple "X" or other mark that a person writes on documents as a proof of identity and ...
s * Typewriters,
photocopier A photocopier (also called copier or copy machine, and formerly Xerox machine, the generic trademark) is a machine that makes copies of documents and other visual images onto paper or plastic film quickly and cheaply. Most modern photocopier ...
s, laser printers, ink-jet printers, fax machines * Chequewriters, rubber stamps, price markers,
label maker Brother P-Touch 540 label printer A label printer is a computer printer that prints on self-adhesive label material and/or card-stock (tags). A label printer with built-in keyboard and display for stand-alone use (not connected to a separate ...
s * Printing processes * Ink,
pencil A pencil () is a writing or drawing implement with a solid pigment core in a protective casing that reduces the risk of core breakage, and keeps it from marking the user's hand. Pencils create marks by physical abrasion, leaving a tra ...
,
paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distribu ...
*Alterations, additions, erasures, obliterations * Indentation detection and/or decipherment * Sequence determination *Physical matching


Principle of identification

The concept of 'identification' as it is applied in the forensic sciences is open to discussion and debate. Nonetheless, the traditional approach in the discipline of forensic document examination is best expressed as follows:
"When any two items possess a combination of independent discriminating elements (characteristics) that are similar and/or correspond in their relationships to one another, of such number and significance as to preclude the possibility of their occurrence by pure coincidence, and there are no inexplicable disparities, it may be concluded that they are the same in nature or are related to a common source (the principle of identification)."
The evaluation of such characteristics is now predominantly subjective though efforts to meaningfully quantify this type of information are ongoing. Subjective evaluation does not mean that the results of properly conducted comparisons will be unreliable or inaccurate. To the contrary, scientific testing has shown that professional document examiners (as a group) out-perform lay-people when comparing handwriting or signatures to assess authorship.Kam et al, A Decade of Writer Identification Proficiency Tests for Forensic Document Examiners, ASQDE, 2003. However, this type of 'subjective' analysis depends greatly upon the competency of an individual examiner. It follows that # an examiner should follow appropriate case examination protocols carefully and evaluate all possible propositions, # an examiner should be properly trained and their training should include adequate testing of their abilities, # the formal case examination procedure should incorporate some form of secondary review (ideally, independent in nature) and # every examiner should make every effort to demonstrate and maintain their competency through professional certification and ongoing proficiency testing.


Handwriting examinations

The examination of handwriting to assess potential authorship proceeds from the above principle of identification by applying it to a comparison of samples of handwritten material. Generally known as ACE-V, there are three stages in the process of examination.Huber & Headrick 1999, pg. 34. As Huber and Headrick explain in their text, these are as follows:Huber & Headrick 1999, pg. 34. # Analysis or Discriminating Element Determination:
The unknown item and the known items must, by analysis, examination, or study, be reduced to a matter of their discriminating elements. These are the habits of behaviour or of performance (i.e., features or characteristics and, in other disciplines, the properties) that serve to differentiate between products or people which may be directly observable, measurable, or otherwise perceptible aspects of the item.
# Comparison:
The discriminating elements of the unknown, observed or determined through analysis, examination, or study, must be compared with those known, observed, or recorded of the standard item(s).
# Evaluation:
Similarities or dissimilarities in discriminating elements will each have a certain value for discrimination purposes, determined by their cause, independence, or likelihood of occurrence. The weight or significance of the similarity or difference of each element must then be considered and the explanation(s) for them proposed.
# Optionally, the procedure may involve a fourth step consisting of verification/validation or peer review. The authors note further that "This process underlies the identification of any matter, person, or thing, by any witness, whether technical, forensic, or not." As such, it is not a formal method, but rather the elements that go into the method.
ASTM ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, an ...
has published a standard guide for the examination of handwriting titled "E2290-07a: Examination of Handwritten Items". Some of the guides listed under "Other Examinations" apply to forensic handwriting comparisons (e.g., E444 or E1658). An alternative guide for the examination of handwriting and signatures has been developed by the Forensic Expertise Profiling Laboratory (School of Human Biosciences,
La Trobe University La Trobe University is a public research university based in Melbourne, Victoria, Australia. Its main campus is located in the suburb of Bundoora. The university was established in 1964, becoming the third university in the state of Victoria a ...
, Victoria, Australia).


Other examinations

Aside from E2290 mentioned above, many standard guides pertaining to the examination of questioned documents have been published by ASTM International. They include the following: :*E444-06 Scope of Work Relating to Forensic Document Examiners :*E2195-02 Terminology: Examination of Questioned Documents :*E1658-08 Terminology: Expressing Conclusions of Forensic Document Examiners :*E1422-05 Test Methods for Forensic Writing Ink Comparison :*E1789-04 Writing Ink Identification :*E2285-03 Examination of Mechanical Checkwriter Impressions :*E2286-03 Examination of Dry Seal Impressions :*E2287-03 Examination of Fracture Patterns and Paper Fibre Impressions on Single-Strike Film Ribbons and Typed Text :*E2288-03 Physical Match of Paper Cuts, Tears, and Perforations in Forensic Document Examinations :*E2289-08 Examination of Rubber Stamp Impressions :*E2291-03 Indentation Examinations :*E2325-05 Non-destructive Examination of Paper :*E2331-04 Examination of Altered Documents :*E2388-05 Minimum Training Requirements for Forensic Document Examiners :*E2389-05 Examination of Documents Produced with Liquid Ink Jet Technology :*E2390-06 Examination of Documents Produced with Toner Technology :*E2494-08 Standard Guide for Examination of Typewritten Items Not all laboratories or examiners use or follow ASTM guidelines. These are guidelines and not requirements. There are other ASTM guides of a more general nature that apply (e.g., E 1732: Terminology Relating to Forensic Science). Copies of ASTM Standards can be obtained from ASTM International.


Common tools of the trade

*Excellent eyesight * Handlens/loupe * Stereomicroscope * Electrostatic detection device (EDD) *Video spectral comparator (VSC)


Professional organizations

Links are provided below


Dedicated to questioned document examination

* American Society of Questioned Document Examiners (ASQDE): USA and Canada * Australasian Society of Forensic Document Examiners Inc. (ASFDE Inc): Australia/Asia (formerly the Australian Society of Forensic Document Examiners) *Associación Professional de Peritos Callígrafos de Cataluña (Spain) *European Network of Forensic Handwriting Experts (ENFHEX within ENFSI) *European Document Experts Working Group (EDEWG within ENFSI) *Southeastern Association of Forensic Document Examiners (SAFDE): Southeast USA * Southwestern Association of Forensic Document Examiners (SWAFDE): Southwest USA * Gesellschaft für Forensische Schriftuntersuchung (GFS): Frankfurt (Germany) *National Association of Document Examiners (NADE) * Association of Forensic Document Examiners (AFDE) * The International Association of Document Examiners (IADE) *The Scientific Association of Forensic Examiners (SAFE) *Sociedad Internacional de Peritos en Documentoscopia (SIPDO): Spain, Latin América


General forensic science associations with QDE sections

*
American Academy of Forensic Sciences The American Academy of Forensic Sciences (AAFS) is a society for forensic science professionals, and was founded in 1948. The society is based in Colorado Springs, Colorado, USA. The AAFS is a multi-disciplinary professional organization that p ...
(AAFS): USA *
Canadian Society of Forensic Science The Canadian Society of Forensic Science (CSFS) is a professional association aimed at maintaining professional standards and promoting and enhancing the study and stature of forensic science. Membership in the society is open internationally to p ...
(CSFS): Canada *Australian and New Zealand Forensic Science Society (ANZFSS) *European Network of Forensic Science Institutes (ENFSI) *Forensic Science Society (FSS): United Kingdom * International Association for Identification (IAI) *Mid-Atlantic Association of Forensic Scientists (MAAFS)


Academic/research groups with interest in QDE

* International Graphonomics Society *
Center of Excellence for Document Analysis and Recognition The Center of Excellence for Document Analysis and Recognition (CEDAR) is a research laboratory at the University at Buffalo, State University of New York. The center was established with funding from the United States Postal Service and National ...
(SUNY) *Purdue Sensor and Printer Forensics (PSAPF) Project *Dr. Mara Merlino at Kentucky State University


Certification

Due to the nature of certification, there are many bodies that provide this service. Most provide certification to individuals from a particular country or geographic area. In some places, the term accreditation may be used instead of certification. Either way, in the present context, it refers to the assessment of an examiner's competency and qualifications by an independent (third-party) organization of professionals.


International (border-less) certifying bodies


Forensic Science Society (UK)

The
Forensic Science Society The Chartered Society of Forensic Sciences (CSFS), formerly the Forensic Science Society, is an international professional society based in the United Kingdom. It was founded in 1959 and is one of the oldest and largest forensic associations in the ...
(UK) provides their members with the opportunity to obtain a Professional Postgraduate Diploma in forensic disciplines, including Questioned Document Examination. The program is accredited by the University of Strathclyde. Successful applicants are entitled to use the postnominal 'FSSocDip'. Since membership in the FSS (UK) is open to anyone regardless of where they live or work, this is effectively an international certification.


United States, Canada and Mexico


American Board of Forensic Document Examiners

The American Board of Forensic Document Examiners, Inc. (ABFDE) provides third-party certification for professional forensic document examiners from Canada, Mexico, the United States of America as well as Australia and New Zealand. The ABFDE is accredited by the Forensic Specialties Accreditation Board.


Board of Forensic Document Examiners

The Board of Forensic Document Examiners (BFDE) provides certification of forensic document examiners. The BFDE is accredited by the Forensic Specialties Accreditation Board.


See also

* Images of signatures * Ontario Centre of Forensic Sciences *
Canadian Identification Society The Canadian Identification Society (CIS) is a bilingual (English- French) professional non-for-profit fellowship of police officers and civilian members who share interests and employment in crime scene investigation. Also known in French as (S ...
*
CEDAR-FOX This is a software system for forensic comparison of handwriting. It was developed at CEDAR, the Center of Excellence for Document Analysis and Recognition at the University at Buffalo. CEDAR-FOX has capabilities for interaction with the question ...


Notes


References

The literature relating to questioned document examination is very extensive. Publications in English, French, German, and other languages are readily available. The following is a very brief list of English-language textbooks: # Osborn, A.S. (1929). ''Questioned Documents'', 2nd ed. Albany, New York: Boyd Printing Company. Reprinted, Chicago: Nelson-Hall Co. #Harrison, W.R. (1958). ''Suspect Documents: Their Scientific Examination''. New York: Praeger. #Conway, J.V.P. (1959). ''Evidential Documents''. Illinois: Charles C Thomas. #Hilton, O. (1982). ''Scientific Examination of Questioned Documents''. New York: Elsevier Science Publishing Co. #Huber R.A. & Headrick A.M. (1999). ''Handwriting Identification: Facts and Fundamentals''. Boca Raton: CRC Press. #Ellen, D. (2005). ''Scientific Examination of Documents: Methods and Techniques, Third Edition''. Boca Raton: CRC Press. #Morris, R. (2000). ''Forensic Handwriting Identification: Fundamental Concepts and Principles''. Academic Press. #Levinson, J. (2001). ''Questioned Documents: A Lawyer's Handbook''. San Diego: Academic Press. #Köller N., Nissen K., Rieß M. & Sadorf E. ''Probabilistische Schlussfolgerungen in Schriftgutachten (Probability Conclusions in Expert Opinions on Handwriting)'', Luchterhand, Munchen (2004) available online in German and English
PDF


External links

*{{Commons category-inline Forensic techniques