1st Edition

Forensic Speaker Identification

By Phil Rose Copyright 2002

    A voice is much more than just a string of words. Voices, unlike fingerprints, are inherently complex. They signal a great deal of information in addition to the intended message: the speakers' sex, for example, or their emotional state, or age. Although evidence from DNA analysis grabs the headlines, DNA can't talk. It can't be recorded planning, carrying-out or confessing to a crime. It can't be so apparently directly incriminating. Perhaps it is these features that contribute to the interest and importance of Forensic Speaker Identification (FSI)

    Introduction. Why Voices are Difficult to Discriminate Forensically. Forensic Phonetic Parameters. Expressing the Outcome. Characterizing Forensic Speaker Identification. The Human Vocal Tract and the Production and Description of Speech Sounds. Phonemics. Speech Acoustics. Speech Perception. What is a Voice? The Likelihood Ratio Revisited: A Demonstration of the Method. Summary and Envoi.

    Biography

    Phil Rose

    "This comprehensive and well written book encompassing pretty well all you need to know about speech recognition/voice identification is one that can be enjoyed by the complete beginner and also can be taken as a basic textbook by the budding student of phonetics and linguistics. Any other interested readers from different forensic disciplines will find it a fascinating introduction … . "
    - Science & Justice, Vol. 43, No. 4, 2003


    "[A]n up-to-date and in-depth account of the discipline of forensic speaker identification. … [W]ith his broad coverage of topics, his clarity of style, and his abundance of illustrations, Rose is able to provide valuable information … Teaching the reader the essentials of [the] scientific evaluation process in forensic speaker recognition is one of the many aspects that make this book by Philip Rose highly recommended."
    - Speech, Language and the Law

    "The voice is dynamic in nature, and forensic analysis necessarily encompasses multiple areas including acoustics, linguistics, physiology, speech pathology, and statistics. [This book] is a highly useful guide to navigating the complexities in these overlapping disciplines, and is sure to become required reading for any forensic practitioner involved in voice comparison. … [This book] is a clearly written and highly detailed text that does an admirable job of outlining the complexities of forensic voice comparison, and is a must-read for any practitioner seeking to stay current in this rapidly evolving field."
    - Et Cetera


    Forensic Speaker Identification explains what FSI involves, and clarifies the problems of inferring identity from speech under the less than ideal conditions typical in forensics. It will allow the reader to appreciate:
    *the complexities of voice sample comparison
    *the probabilistic nature of the technique - it will not yield absolute identification or exclusion of a suspect
    *the difficulties introduced by differential variation within and between voices and the generally poor degree of control over forensic samples
    *acoustic and auditory comparison and the comparison of linguistic and non-linguistic features
    *the expertise required in linguistics, acoustics and statistics.

    This book has been written for forensic scientists, the legal profession and law enforcement officers. It's accessible to those with no previous knowledge of FSI, or of phonetics or acoustics. It can also be used as a base for teaching tertiary level courses in aspects of phonetics.
    This practical, lucid text takes the reader through all the underpinning knowledge necessary, and will bring much needed clarity to an important technique.