Non-traditional Authorship Attribution : The Contribution of Forensic Linguistics

INTRODUCTION
Black’s Law Dictionary (648) defines forensic
linguistics as:A technique concerned with in-depth evaluation of linguistic characteristics of text, including grammar, syntax, spelling, vocabulary and phraseology, which is accomplished through a comparison of textual
material of known and unknown authorship, in an
attempt to disclose idiosyncracies peculiar to authorship to determine whether the authors could be identical.
At the 2002 ALLC/ACH Conference in Tuebingen,
Laszlo Hunyadi et al. discussed some of the
contributions that humanities computing makes to
forensic linguistics. In this paper I point out the many contributions that forensic linguistics has and is making
to the larger field of non-traditional authorship
attribution -- contributions that are unknown or largely ignored by most non-forensic practitioners of non-
traditional authorship attribution (this statement is based on the lack of references to the wealth of studies in
forensic linguistics -- a quick glance at the bibliography will show some exceptions):
1) Immediacy
2) Techniques
3) Scientific Validity
4) Gatekeeping 5) Levels of Proof
6) Rules of evidence
7) Organization
The paper goes on to propose closer formal ties between the ALLC/ACH and the IAFL. In each of the following
sections, there is an emphasis on how the forensic
techniques should be employed by the non-forensic
practitioner and on the contributions of humanities
computing to the field.
IMMEDIACY
This section discusses how immediacy forces a more
careful, more restrictive methodology on the forensic practitioner (versus the non-forensic):
Forensic linguistics is a sub-set of authorship
attribution that is much more immediate and in many ways demands a “correct” attribution. Forensic
linguistics often deals in criminal guilt or innocence
-- with serious ramifications -- even life or death!
TECHNIQUES
This section discusses:
1) The necessity of employing corpus linguistic
techniques.
a) Looking at style markers as deviations from the norm.
b) Looking at grammatical, stylistic, spelling,
punctuation, and orthographical errors as style
markers.
c) The limiting of one control group to “suspects.”
2) The need for non-forensic practitioners to acquire
the skills necessary to navigate bibliographic
research in forensics (primary and secondary
resources in case law -- and the many
commentaries).
SCIENTIFIC VALIDITY
This section discusses:
1) The concept that all scientific methods should be brought to bear on an authorship problem -- e.g. handwriting analysis, paper analysis, type font
analysis.
2) The strict definition of expert witness -- and the role they are allowed to play -- e.g. guides to help the jury interpret the facts.
3) How methodology must be “generally accepted by the community of scholars” to be allowed.
GATEKEEPING
This section discusses:
1) The role of the courts (of various countries) as
gatekeepers.
2) The role of the International Association of
Forensic Linguists IIAFL as gatekeeper and
certifier of gatekeepers.
This does not mean that there are not flaws in the system -- e.g. allowing the Morton CUSUM method as a valid technique even after its debunking on live TV.
LEVELS OF PROOF
This section discusses:
How the “answer” is presented - while non-forensic practitioners for the most part present “probabilities”,
forensic linguistics presents a “preponderance of
evidence” concept and one of being “beyond a
reasonable doubt.”
RULES OF EVIDENCE
This section discusses:
The intricacies of the rules of evidence and how these rules can give direction to non-forensic
attribution studies. Rules of evidence are not
universal -- different countries have different rules -- in the United States, different states have different les. A set of rules distilled from all those available is advocated or the non-forensic practitioner.
a) Dauber
b) Post-Dauber
ORGANIZATION
This section discusses:
1) The IAFL, a “professional” organization with the
requirement that its full members show evidence of “linguistic qualifications.”
a) The IAFL’s journal -- Speech, Language and the Law (Formerly - Forensic Linguistics) Having a paper published here -- the implicit nihil obstat of the IAFL -- gives added weight to the credentials of the practitioner. Among other important journals are, Expert Evidence, Forensic Science International, and Journal of Forensic Document Examination.
b) The IAFL’s conference
The IAFL holds a biennial conference. The last one was in July, 2005 at Cardiff University, UK. Seven of the presented papers are of interest (and importance) to non-forensic practitioners -- e.g. Sanchez et al.’s
“Intra and Inter-author Comparisons: The Case of
Function Words: Are Function Words Really
Functional in Stylometric Studies of Authorship
Attribution.”
c) There are some members (formal and contributing) of ALLC and ACH that are also members of the
IAFL but their work published in non-forensic
journals is quite different.
CONCLUSION
Forensic linguistis is not a “perfect” discipline. One unfortunate aspect of forensic linguistics is the
adversarial role in presenting evidence -- many forensic
linguistic presentations, while not necessarily fraudulent
or even unethical are not in the best interests of
practitioners who want to present the “whole truth.” Another unfortunate side-effect of the judicial system on the complete reporting of authorship studies is the all
too common practice of “sealing” court records when a settlement is reached outside of the courtroom. I have seen some of these sealed records and only hope that the techniques will be duplicated and published elsewhere.I do not want to give the impression that non-forensic
attribution is a poor cousin with nothing to offer -- the many disciplines that form the bulk of the field (e.g. computer science, stylistics, statistics) are the “core” -- but this is for another time.
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