John Olssons book， released in 2008 by the publisher of Continuum， New York， gives an excellent introduction to a relatively new linguistic discipline. It is written in a simple， comprehensible style and is intended for anyone interested in the subject （from the students of linguistics through psychologists and sociologists to lawyers）. It seeks to introduce the broad range of topics and fields included in the realm of forensic linguistics， comprising both theory and practice in real cases. The book does a very good job of introducing the main topic areas of forensic linguistics.

The book is divided into 13 chapters and covers all areas of forensic linguistics （definition of authorship of texts， plagiarism recognition， language variation and their interpretation， statement analysis - mostly eyewitness to forensic phonetics）. At the beginning there is the development of forensic linguistics and previous research of this branch of linguistics. The author then informs us about the legal provisions in different countries regarding forensic linguistic evidence in the court. The real strength of this book lies in the practical exercises， typical those real-life examples in court. There is a wide range of cases and data used in the book， from emergency calls to death statements. Importantly the exercises are accompanied by discussion and commentaries which enables students to discuss about real cases and develop their analytical skills.

In addition to the simplicity that significantly facilitates understanding， the book also contains particularly helpful recommendations for further reading. The author cites the bibliography of the work in detail and thus makes it much easier to find details of those cases in the literature. He also mentions in several places that the book is only a brief glimpse of much wider and more demanding issues. Olsson intended to write a book that would be a guide to anyone who is interested in forensic linguistics. At the same time， he wanted to make the book closer to the general public and make it interesting. It seems that， for this reason， it is quite simple and even briefly explains the statistical methods that are critical to such research. The first section introduces the main concepts of authorship analysis， as well as some of the key complexities. Chapter 2 defines the field of forensic linguistics， by explaining the definitions of different kinds of legal texts， the procedure of legal system， and also showing the history of forensic linguistics.

The second section discusses individual language use and the variation. Chapter 3 poses background questions relating to the existence of a unique language style in each individual and intend to prove the uniqueness of individual language use. In chapter 4， the author discusses the notion of intra-author variation and inter-author variation. He explains how and why an authors texts vary from each other and in which way Intra-author variation is distinguished from inter-author variation.

The third and largest section introduces different kinds of linguistic evidence and looks at the relation between language and the legal process. Olsson discusses a lot of linguistic proof in this section to increase readers` interest in forensic linguistics research. Chapter 5 presents the outline of an authorship comparison method， involving statistical analysis and discussion of statistical matters in authorship. Chapter 6 offers a brief outline of how courts in different countries view expert evidence and discusses different acceptance of linguistic proof. Chapter 7 and 8 cite some types of case and consider the linguistic issues at stake in those cases， ranging from textual influence， plagiarism to witness intimidation， content of threat communications， hate mail， blackmail， text provenance， poison mail， authorship of witness and other statements， relating to the linguistic issues， e.g. contemporaneity of text， power and disinformation， memory for language， linguistic influence on witnesses， linguistic provenance of written text. Chapter 9 makes further efforts on plagiarism， focusing on what happens in plagiarism linguistically - what do plagiarists do？

The fourth section then focuses on different forms of language in legal process. Chapter 11 is primarily concerned with investigative linguistics， looking at some aspects of emergency calls， hate and threat mails， final death statements， etc. In the example of Lindbergh kidnapping case， Olsson reveals the ransom note Lindbergh stated： ‘We warn you for making anyding public or for notify the polise the child is in gute care. Here the kidnapper claims the child is in good hands. “However， the note would have to have been written before the perpetrator entered the premises， and so we see immediately that the claim is false， since the kidnapper had not even encountered the child when he wrote the note.” Chapter 12 explains the definition of forensic linguistics， which is “the use of phonetic techniques primarily in the analysis of the voice applied to criminal investigations， including technical voice comparisons， recognition， transcription of spoken language including transcription of disputed utterances， speech signal enhancement and the authentication of recordings.” Chapter 13 shows how the task of transcribing forensic texts is underestimated by professionals in the legal profession and explains why transcribing forensic texts is so crucial in legal process and also gives notes on forensic transcription. The book ends with appendices， which provide a list of the texts used in real-life legal cases， containing “a forged will， a statement alleging sexual assault， a letter from a pipe bomber attempting to rationalize his crimes， a complaint about the practice of verballing， a young mother claiming that she was carjacked and her children kidnapped， the same woman appealing at a press conference for the safe return of her children， and， finally， the same woman admitting to having killed her children.”

The most elaborate chapters of the book are those that deal with determining the credibility of the text and determining authorship. Using actual examples from various cases of suicide， terrorist threats， theft， and ransom search， leads us step by step in analyzing texts by confirming or eliminating doubts about the authorship and credibility of the message. Surely， the most interesting and most dubious case of suicide by Gilfoyle， a woman allegedly committed suicide， and the authenticity of her farewell letter got checked. It analyzes the length of sentences and passages， choice of words and grammatical forms， sentence structure and substantive logic. In the analysis of concrete texts for the reader， there is no ambiguity. Each term is defined， illustrated and explained. Indeed， in some chapters， the author used statistical tables （e.g. table 4.6 the density for the Gilfoyle texts， p. 39） and the terms used are interpreted thoroughly. （e.g. duality of authorship） Olsson sometimes discusses possible issues and addresses certain passages （e.g. What is Scientific method， p. 64） and gives an answer. Apart from the farewell letters of the suicide and the threatening letters or the so-called hate mail， this book also deals with analysis of the texts of seeking ransom in kidnappings.

Unfortunately， the book forensic linguistics has not paid much attention to forensic phonetics. Only around thirty pages （p.155 - p.187） give a brief overview of phonetics in general （voice recognition， anatomy of spectrograms， voice comparison） and that chapter doesn`t mention the methods and practice of the voice recognition， which is considered a very important part of forensic linguistics. Probably because the author did not deal with that field of forensic phonetics， the author dedicates few pages and little attention to this topic.

The book Forensic Linguistics is a very interesting presentation of a linguistic discipline that is still young in our country and will surely help us to get acquainted with the subject and the method of forensic linguistics researches. It may help expand our linguistic knowledge and opens the door to a relatively underdeveloped area， which may encourage further research. As at the beginning of the chapter， he says， “ It is likely in the future that increasing numbers of those seeking to enter the field of Forensic Linguistics will have additional qualifications in areas such as the law and mathematics and statistics， and gain greater understanding of scientific techniques， methods and presentation. With a broad but accurate insight into the law and an appreciation of how science is ‘done in other fields than their own， forensic linguists of the future will have greater means at their disposal than the founders of the discipline.”

References：

[1]Hollien， H. Forensic Voice Identication[M]. London： Academic Press，2002.

[2]Olsson， J. Forensic Linguistics. An Introduction to Language， Crime and the Law[J]. London and New York： Continuum，2004.

[3]Olsson， J. Forensic Linguistics[J]. London and New York： Continuum，20082nd ed.

[4]Olsson， J. and Luchjenbroers， J. Forensic Linguistics[J]. London： Bloomsbury，2014，3rd ed.

【作者簡介】梁依睿（1992-），女，四川綿陽人，浙江大學2017級外國語言學及應用語言學專業(yè)碩士研究生，研究方向：語言學與話語研究。