Forensic linguistics and stylistics

DEFINITION: Study of the interaction of language and the law, including using language as evidence.

SIGNIFICANCE: Forensic linguistics and stylistics often play crucial roles in police investigations, evidence gathering, and courtroom testimony. Many forensic linguists provide expert testimony relating to such issues as the likelihood that a particular individual produced certain documents or was the person speaking on a questioned recording. Such experts are also called upon to determine the likelihood that persons might be lying on the basis of their voices and linguistic qualities.

Forensic linguistics and stylistics are tools used to gain information about individuals on the basis of the language they have used. Many different types of crimes can result in written or spoken evidence that may be used to help determine the identities of the criminals. Some written or spoken evidence may be left by criminals on purpose, such as ransom notes or threatening voice-mail messages. Other linguistic evidence may be provided inadvertently, such as in recorded conversations or in notes between accomplices. No matter how the investigators acquire such evidence, forensic linguistic specialists can analyze it to provide information about the individuals in question.

According to a 2023 study published in the journal Cogent Arts & Humanities, the field of forensic linguistics first developed in the 1930s and began to develop into a widely accepted field of science in the 1990s. By the first decades of the twenty-first century, the United States and the United Kingdom were at the leading edge of using forensic linguistics as an investigative tool, while Spain, Germany, and China also used the method.

Analysis of Written Language

Written language is extremely complex. Letters are arranged into words, and words are arranged into sentences that convey meaning to other people when the authors are not around to explain their intentions. Written documents, even very short ones, often contain clues that can help investigators determine the identities of the authors. Forensic stylistics is the study of documents in an attempt to determine authorship. (The term “forensic stylistics” is sometimes used interchangeably with the term “forensic linguistics,” but in most cases “forensic stylistics” is the specific term applied to the use of linguistic methods to determine authorship of particular documents.) Such analysis may be undertaken if there is a suspected author or, if no specific individual is suspected, as an attempt to determine as much information as possible about the author.

When investigators have concluded that a given individual is the suspected author of the document in question, the first step in the forensic linguist’s work is often to acquire a writing sample from the suspected individual. If the document of interest was handwritten, the investigator generally instructs the suspected individual to copy the document by hand and may request a copy written from dictation. The forensic linguist also then generally collects samples of other writings done by the individual on various topics and in various circumstances.

After the samples have been collected, the forensic linguist begins a careful comparison of the samples with the questioned document. During this analysis, other experts in related fields, such as forensic handwriting analysis and questioned document examination, are often also at work attempting to determine whether the suspected individual is likely to have been the author of the document. The linguist compares various aspects of the samples to those aspects of the original document. Spelling and grammar are compared as well as syntax, word choice, vocabulary, punctuation, and other elements of written language. Spelling and grammatical mistakes are often consistent in specific individuals over time; for instance, an individual who misspells the word “believe” as “beleive” in one instance is likely to do so in many different circumstances. The forensic stylistic expert thus compares the dictated sample and other samples from the suspected author to the questioned document to check spelling and punctuation choices.

If investigators have located no one who is believed to have been the author of the original document, a forensic stylistic expert is often called upon to examine the document in an effort to gain information about the author. Instead of obtaining samples for comparison, the expert must use the document itself to derive as much information as possible. Information about the level of education, nationality, and even age of the author may be revealed by the grammar and spelling in the document, as well as by the level of the vocabulary used and the complexity of the sentence structure. The presence of certain word choices and sentence structures that are more common to some regions than to others may enable the forensic linguist to define the likely identity of the author further.

Forensic stylistics is also important in the investigation of documents that are being presented as the works of specific individuals but the authenticity of which is being questioned. Documents such as wills that have been drawn up by individuals without the involvement of attorneys may come under such questioning. In such cases, experts in forensic stylistics can analyze the writing styles and contents of the documents to help determine their authenticity. Documents purported to have been written by famous historical individuals, such as letters from George Washington or the diaries presented as being written by Adolf Hitler, often are submitted for stylistic analysis in addition to handwriting and document analysis in efforts to prove or disprove their authenticity.

Analysis of Spoken Language

Spoken language can also provide valuable information during the investigation of crimes. Whether criminals leave samples of spoken language on purpose (as in threatening phone calls) or inadvertently (as when a security camera records the voice of a robber during a bank robbery), forensic linguists can use such samples to help determine important information about the criminals’ identities.

When a suspect has been identified in a case, the forensic linguist can request that samples of the individual’s voice be recorded for comparison with the original voice recording. The forensic linguist might want to work with several kinds of samples; for example, the suspect might be recorded repeating specific words and phrases, making a general statement on a certain topic, or simply speaking freely. The linguist might also seek out samples of recordings of the suspect speaking in other circumstances. The linguist then compares the samples with the original recording across a number of different variables.

When no specific individual has been identified as a suspect, the forensic linguist uses the available evidence sample to try to gain as much information as possible about the individual, including likely gender, race, and education level as well as information about the country or region in which the individual grew up. Many differences in speech and pronunciation, as well as word choice and usage, can give details about where a person grew up or has spent many years living. A regional accent can be an important clue to a criminal’s identity.

Details of an individual’s spoken language can provide information about race, ethnicity, nationality, and educational level that can help investigators narrow their search. Many individuals who have learned English as a second language have lingering traces of their first languages that can help linguists make educated guesses about what countries or areas of the world they are from. Native English speakers may also have accents specific to the areas in which they learned the language. Some American accents, such as those associated with Brooklyn, New York, and upper Minnesota, are widely recognized and well documented in popular media. Linguists have documented many other, less widely recognized accents as well, and their knowledge of such accents can help them identify the likely areas in which suspects live or grew up. Although many individuals gain or lose accents to an extent over time, the majority retain at least some traces of the pronunciation common in the areas in which they first learned to speak.

In addition to accents, certain words and phrases are used more commonly in some regions than in others. Word and phrase choices also tend to differ among population subgroups, such as age and ethnic groupings, within specific areas.

Bibliography

Alduais, Ahmed, Mohammed Ali Al-Khulaidi, Silvia Allegretta, and Mona Mohammed Abdulkhalek. "Forensic Linguistics: A Scientometric Review." Cogent Arts & Humanities, 23 May 2023, doi.org/10.1080/23311983.2023.2214387. Accessed 15 Aug. 2024.

Coulthard, Malcolm, et al. An Introduction to Forensic Linguistics: Language in Evidence. 2nd ed., Routledge, 2017.

Gibbons, John. Forensic Linguistics: An Introduction to Language in the Justice System. Blackwell Publishing, 2003.

McMenamin, Gerald R., editor. Forensic Linguistics: Advances in Forensic Stylistics. CRC Press, 2002.

Olsson, John, and June Luchjenbroers. Forensic Linguistics. 3rd ed., Bloomsbury, 2014.

Tanner, Dennis C., and Matthew E. Tanner. Forensic Aspects of Speech Patterns: Voice Prints, Speaker Profiling, Lie and Intoxication Detection. Lawyers & Judges Publishing, 2004.