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Forensic footwear evidence
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|Auguste Ambroise Tardieu
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The range of topics within forensic linguistics is diverse but research occurs in the following areas:
The study of the language of legal texts encompasses a wide range of text types and forms of analysis. It includes analysing the linguistics of documents as diverse as Acts of Parliament (or other law-making body), private wills, court judgements and summonses and the statutes of other bodies, such as States and government departments. One important area is that of the transformative effect of Norman French and Ecclesiastic Latin on the development of the English common law, and the evolution of the legal argot associated with it. It can also refer to the ongoing attempts at making legal language more comprehensible to laypeople.
This area examines language as it is used in cross-examination, evidence presentation, judge's direction, summing up to the jury, police cautions, 'police talk', interview techniques, the questioning process in court and in other areas such as police interviews, amongst other things.
Linguists have provided evidence in:
and a number of other areas. Some areas are more controversial than others. The identification of whether a given individual said or wrote something relies on analysis of their idiolect. or particular patterns of language use (vocabulary, collocations, pronunciation, spelling, grammar, etc). The idiolect is a theoretical construct based on the idea that there is linguistic variation at the group level and hence there may also be linguistic variation at the individual level. As the well-respected variationist William Labov pointed out thirty years ago, nobody has yet found "homogenous data" in idiolects. There are many reasons why it is difficult to provide such evidence. Firstly, language is not an inherited property, but one which is socially acquired. The acquisition process is continuous throughout life. This means that an individual's use of language is always susceptible to variation from a variety of sources, including other speakers, the media and macro-social changes. Education can have a profoundly homogenizing effect on language use. In formal texts, such as newspaper articles, novels, academic papers, etc., the effect of the genre on the structure of language can be one of homogenising or, indeed, one of confounding, given that a genre is a "socially constructed...typified response to recurrent rhetorical situations". Research is ongoing into authorship identification. The term authorship attribution is now felt to be too deterministic. Specialist databases (corpora) of language are now frequently being used by forensic linguists, including corpora of suicide notes, mobile phone texts, police statements, police interview records and witness statements.
Forensic linguists have given expert evidence in a wide variety of cases, including abuse of process, where police statements were found to be too similar to have been independently produced by police officers; the authorship of hate mail; the authorship of letters to an Internet child pornography service; the contemporaneity of an arsonist's diary; the comparison between a set of mobile phone texts and a suspect's police interview, and the reconstruction of a mobile phone text conversation. Forensic linguist John Olsson gave evidence in a murder trial on the meaning of 'jooking' in connection with a stabbing, Trial of Rehan Asghar, Central Criminal Court, London, January 2008. Earlier cases included an appeal against the conviction of Derek Bentley and the identification of Theodore Kaczynski as the so-called "Unabomber". During the appeal against the conviction of the Bridgewater Four, the forensic linguist examined the written confession of Patrick Molloy, one of the defendants — a confession which he had retracted immediately — and a written record of an interview which the police claimed had taken place immediately before the confession was dictated. Molloy denied that the interview had ever taken place, and the analysis indicated that the answers in the interview were not consistent with the questions being asked. The linguist came to the conclusion that the interview had been fabricated by police. Later the conviction against the Bridgewater Four was quashed before the linguist in the case Malcolm Coulthard could produce his evidence. Additionally, in an Australian case reported by Eagleson, a "farewell letter" had apparently been written by a woman prior to her disappearance. The letter was compared with a sample of her previous writing and that of her husband. Eagleson came to the conclusion that the letter had been written by the husband of the missing woman, who subsequently confessed to having written it and to having killed his wife. The features analysed included sentence breaks, marked themes, and deletion of prepositions.
Forensic linguistics contributed to the overturning of Derek Bentley's conviction for murder in 1998 although there were other, non-linguistic issues. Nineteen-year-old Bentley was hanged in 1953 for his part in the murder of PC Sidney Miles; the fatal shot had been fired by Bentley's sixteen-year-old friend, Christopher Craig, when Bentley was already in police custody. Bentley, who had a mental age of eleven and was functionally illiterate, was convicted partly on the basis of his statement to police, allegedly transcribed verbatim from a spoken monologue. Linguist Malcolm Coulthard examined the text when the case was reopened, and found a number of features which indicated police co-authorship, and which suggested that at least part of the statement resulted from questions and answers, as Bentley claimed, and was not, as police claimed, a "verbatim record of dictated monologue". One such feature was the use of the word "then", which Coulthard and his colleague David Woolls found to be the eighth most frequently-occurring word in Bentley's text, as compared with the 58th most frequent word in spoken English, and the 83rd most frequent word in English in general (according to the 1.5-million-word Bank of English corpus they were using). Feeling that the use of that word could be expected to be higher than average in witness statements (which generally report a sequence of events and show concern for accuracy about time), Two corpora were compiled, one of witness statements and one of police statements. The word "then" occurred once every 930 words in the former but once every 78 words in the latter, compared with the Bank of English corpus where it occurred once every 500 words, and Bentley's text where it occurred once every 53 words. The focus then turned to the use of the word "then". The frequent post-positioning of temporal (time-related) "then" after the grammatical subject ("I then" rather than "then I"), which occurred seven times in the 582-word text, was also noted. The Bank of English spoken corpus showed "then I" to occur ten times more frequently than "I then", the latter occurring only once every 165,000 words. That structure did not occur at all in the corpus of witness statements, but occurred once every 119 words in the corpus of police statements. These features, combined with many others, contributed to a successful argument that the Bentley "confession" was, in part, the written work of police officers, and not simply a word-for-word transcript of Bentley's spoken statement as the police alleged.
In the case of Theodore Kaczynski, who was eventually convicted of being the "Unabomber", family members recognized his writing style from the published 35,000-word Industrial Society and Its Future (commonly called the "Unabomber Manifesto"), and notified the authorities. FBI agents searching Kaczynski's hut found hundreds of documents written by Kaczynski, but not published anywhere. An analysis produced by FBI Supervisory Special Agent James R. Fitzgerald identified numerous lexical items and phrases common to the two documents. Some were more distinctive than others, but the prosecution (assisted by Vassar Professor of English Donald Foster) successfully argued that even the more common words and phrases being used by Kaczynski became distinctive when used in combination with each other.
Julie Turner, a 40 year old woman living in Yorkshire, went missing one summer evening in 2005. Relatives became concerned when she did not return after an appointment with a male friend. She was reported missing on 8 June 2005 and the following afternoon her partner received this mobile phone text: "Stopping at jills, back later need to sort my head out". Two days after Julie went missing another text was received: "Tell kids not to worry. sorting my life out. (sic) be in touch to get some things". Her partner thought it odd that she had not contacted the children. Police interviewed Howard Simmerson, a male friend, at his place of work on 10 June 2005. He denied any knowledge of her whereabouts. After analysis of many hours of close circuit television footage police observed Simmerson driving a four-wheel drive vehicle with a barrel secured to the rear of the vehicle. Similar references in letters Simmerson had written to the language of the mobile phone texts were found, as well as several unusual orthographic and punctuation features. Olsson suggested to police that this evidence indicated a possibility of Simmerson being aware of the contents of the text messages. On being confronted with this intelligence Simmerson admitted that Julie had been in his vehicle, but claimed that she had opened his glove compartment and found a weapon in there with which she had accidentally shot herself. Her body was in the barrel that had been on the back of his four-wheel drive vehicle. Police eventually found the barrel and recovered the body. Simmerson was found guilty at Sheffield Crown Court on 8 November, 2005, of Ms Turner's murder. He was sentenced to life imprisonment by Mr Justice Pitcher.