Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-23T08:46:48.242Z Has data issue: false hasContentIssue false

Unmasking Identity: Speaker Profiling for Forensic Linguistic Purposes

Published online by Cambridge University Press:  13 March 2015

Natalie Schilling
Affiliation:
Georgetown [email protected]
Alexandria Marsters
Affiliation:
Georgetown [email protected]

Abstract

When an anonymous speech sample is associated with a criminal matter, for example in the case of a phoned-in bomb threat or ransom demand, forensic linguistic profiling may be used to infer attributes of the speaker from his or her linguistic characteristics. In this review, we present research and case examples outlining what types of speaker characteristics are discoverable via speaker profiling by expert linguists, for example, gender, age, and region of socialization. We also consider different methods in speaker profiling, including aural-perceptual, acoustic phonetic, and automated, and briefly discuss expert versus nonexpert speaker profiling, as well as the proper role of linguistic profilers versus law enforcement and legal professionals, government agencies, and others with whom forensic linguists work. Finally, we address the problem of voice and dialect disguise, including what types of disguises criminals may effect and what methods can be used to unmask them, including human and automated. We illustrate our points by alluding, throughout the review, to various elements of a case in which we recently served as expert linguistic profilers.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

ANNOTATED BIBLIOGRAPHY

Eriksson, Anders. (2010). The disguised voice: Imitating accents or speech styles and impersonating individuals. In Llamas, Carmen & Watt, Dominic (eds.), Language and Identities (pp. 7685). Edinburgh, Scotland: Edinburgh University Press.

The author provided an overview of studies of accent and voice disguise over the past 10+ years, noting that while disguise is not necessarily very common, it can have quite an adverse effect on profiling efforts when employed. In particular, while expert analysts are quite adept at detecting disguise, there currently exist no reliable automatic systems for the detection of disguise. Eriksson advocated for the creation of a database of paired disguised-undisguised speech samples on which to train automated systems. He also called for more research on foreign accent imitation. He discussed the factors that impact people's perceptions of speaker identity, including familiarity with the spoken language/dialect and method/type of disguise (e.g., accent vs. voice).

Jessen, Michael. (2007). Speaker classification in forensic phonetics and acoustics. In Müller, Christian (ed.), Speaker classification I (pp. 180204). Berlin, Germany: Springer.

Based on his own and a review of others’ studies and casework, Jessen discussed voice analysis (i.e., speaker profiling) and voice comparison (i.e., speaker identification). The focus is on which class characteristics seem to be inferable from speech. These include gender, age, so-called “sociolect” (profession, education level), foreign accent, native dialect, and medical conditions. Jessen also noted that it is possible to infer physical characteristics like height from frequency measurements. Jessen pointed to a number of complications in identifying each of the various speaker attributes; the current review further problematizes class characterizations from a sociolinguistic perspective.

Watt, Dominic. (2010). The Identification of the individual through speech. In Llamas, Carmen & Watt, Dominic (eds.), Language and identities (pp. 7685). Edinburgh, Scotland: Edinburgh University Press.

This article presents an overview of speaker identification, which includes profiling unknown speakers for linguistic features indicative of class characteristics, as well as identification of specific individuals. Watt discussed both “lay” or “naïve” speaker identification—day-to-day, impressionistic identification of individuals by listeners untrained in phonetics—and “technical” speaker identification—the examination of a speech sample by a trained speech analysts, using auditory analysis, acoustic phonetic analysis, and automatic speaker recognition technology. The focus is broader than the current review, which focuses more narrowly on expert speaker profiling.

REFERENCES

Ash, Sharon. (1988). Speaker identification in sociolinguistics and criminal law. In Ferrara, Kathleen (ed.), Linguistic Change and Contact: NWAV-XVI (pp. 2533). Austin: University of Texas.Google Scholar
Baugh, John. (2002). Linguistic profiling. In Makoni, Sinfree, Smitherman, Geneva, Ball, Arnetha F., & Spears, Arthur K. (eds.), Black linguistics: Language, society, and politics in Africa and the Americas (pp. 155168). New York, NY: Routledge.Google Scholar
Bing, Janet M., & Bergvall, Victoria L. (1996) The question of questions: Beyond binary thinking. In Bergvall, Victoria L., Bing, Janet M., & Freed, Alice F. (eds.), Rethinking language and gender research: Theory and practice (pp. 130). New York, NY: Longman.Google Scholar
Butters, Ronald R., Espy, Thomas, & Altsuler, Kent. (1993). The imitation of dialect for illegal purposes: An empirical study. Paper presented at New Ways of Analyzing Variation 22, Ottawa, Canada.Google Scholar
Cambier-Langeveld, Tina. (2010). The role of linguists and native speakers in language analysis for the determination of speaker origin. International Journal of Speech, Language and the Law, 17 (1), 6793.CrossRefGoogle Scholar
Chambers, J. K. (1992). Dialect acquisition. Language, 68 (4), 673705.CrossRefGoogle Scholar
Clark, J. Allen, Boersma, P. Dee, & Olmsted, Dawn M. (2006). Name that tune: Call discrimination and individual recognition in Magellanic penguins. Animal Behavior, 72 (5), 11411148.CrossRefGoogle Scholar
Clark, Jessica, & Foulkes, Paul. (2007). Identification of voices in electronically disguised speech. International Journal of Speech Language and the Law, 14 (2), 195221.Google Scholar
Clopper, Cynthia G., & Pisoni, David B. (2004). Some acoustic cues for the perceptual categorization of American English regional dialects. Journal of Phonetics, 32 (1), 111140.CrossRefGoogle ScholarPubMed
Clopper, Cynthia, & Pisoni, David B. (2005). Perception of dialect variation. In Pisoni, David B. & Remez, Robert E. (eds.), The handbook of speech perception (pp. 313337). Oxford, UK: Blackwell.Google Scholar
Cukor-Avila, Patricia, & Bailey, Guy. (2013). Real time and apparent time. In Chambers, J. K. & Schilling, Natalie (eds.), The handbook of language variation and change (2nd ed., pp. 239262). Oxford, UK: Wiley-Blackwell.Google Scholar
Eckert, Penelope. (1997). Age as a sociolinguistic variable. In Coulmas, Florian (ed.), The handbook of sociolinguistics (pp. 151167). Malden, MA: Blackwell.Google Scholar
Ellis, Stanley. (1994). The Yorkshire Ripper enquiry: Part I. Forensic Linguistics 1 (2), 197206.Google Scholar
Eriksson, Anders. (2010). The disguised voice: Imitating accents or speech styles and impersonating individuals. In Llamas, Carmen & Watt, Dominic (eds.), Language and Identities (pp. 7685). Edinburgh, Scotland: Edinburgh University Press.Google Scholar
Eriksson, Anders, & Lacerda, Francisco. (2007). Charlatanry in forensic speech science: A problem to be taken seriously. International Journal of Speech, Language and the Law, 14 (2), 169193.CrossRefGoogle Scholar
Fecher, Natalie, & Watt, Dominic. (2011). Speaking under cover: The effect of face-concealing garments on spectral properties of fricatives. In Lee, Wai-Sum & Zee, Eric (eds.), Proceedings of the 17th International Congress of Phonetic Sciences (pp. 663666). Hong Kong: City University of Hong Kong.Google Scholar
Fecher, Natalie, & Watt, Dominic. (2012). Effects of forensically-realistic facial concealment on auditory-visual consonant recognition in quiet and noise conditions. In Ouni, Slim, Berthomier, Frédéric, & Jesse, Alexandra (eds.), Proceedings from the 12th International Conference on Auditory-Visual Speech Processing (pp. 8186). Annecy, France: Inria.Google Scholar
Fought, Carmen. (2003). Chicano English in context. New York, NY: Palgrave Macmillan.Google Scholar
Foulkes, Paul, & Wilson, Kim. (2011). Language analysis for the determination of origin: An empirical study. In Lee, Wai-Sum & Zee, Eric (eds.), Proceedings of the 17th International Congress of Phonetic Sciences (pp. 691694). Hong Kong: City University of Hong Kong.Google Scholar
Fraser, Helen. (2011). The role of linguists and native speakers in language analysis for the determination of speaker origin: A response to Tina Cambier-Langeveld. International Journal of Speech, Language and the Law, 18 (1), 121130.CrossRefGoogle Scholar
French, Peter, & Harrison, Philip (2007). Position Statement concerning use of impressionistic likelihood terms in forensic speaker comparison cases. International Journal of Speech, Language and the Law, 14 (1), 137144.Google Scholar
French, Peter, Harrison, Philip, & Windsor Lewis, Jack. (2007). R v John Samuel Humble: The Yorkshire Ripper Hoaxer trial. International Journal of Speech, Language and the Law, 13 (2), 255273.CrossRefGoogle Scholar
French, Peter, & Stevens, Louisa. (2013). Forensic speech science. In Jones, Mark. J. & Knight, Rachel-Anne (eds.), The Bloomsbury companion to phonetics (pp. 183197). New York, NY: Bloomsbury.Google Scholar
Gunn, David. (2014). Spanish accent imitation for voice disguise. (Unpublished master's research paper). Washington, DC: Georgetown University.Google Scholar
Hollien, Harry Francis. (2002). Forensic voice identification, San Diego, CA: Academic Press.Google Scholar
Jessen, Michael. (2007). Speaker classification in forensic phonetics and acoustics. In Müller, Christian (ed.), Speaker classification I (pp. 180204). Berlin, Germany: Springer.CrossRefGoogle Scholar
Jessen, Michael. (2008). Forensic phonetics. Language and Linguistic Compass, 2 (4), 671711.CrossRefGoogle Scholar
Koppel, Moshe, Schler, Jonathan, & Argamon, Shlomo. (2009). Computational methods in authorship attribution. Journal of the American Society for Information Science and Technology, 60 (1), 926.Google Scholar
Köster, Olaf, Kehrein, Roland, Masthoff, Karen, & Boubaker, Yasmine H adj (2012). The tell-tale accent: Identification of regionally marked speech in German telephone conversations by forensic phoneticians. The International Journal of Speech, Language and the Law, 19 (1), 5171.Google Scholar
Künzel, Hermann J. (1987). Sprechererkennung: Grundzüge forensischer Sprachverarbeitung. Heidelberg, Germany: Kriminalistik-Verlag.Google Scholar
Labov, William. (1994). Principles of linguistic change: Vol. 1. Internal factors. Malden, MA: Wiley-Blackwell.Google Scholar
Labov, William. (2007). Transmission and diffusion. Language, 83 (2), 344387.CrossRefGoogle Scholar
Labov, William, Ash, Sharon, & Boberg, Charles. (2006). The atlas of North American English: Phonetics, phonology, and sound change. New York, NY: Mouton de Gruyter.CrossRefGoogle Scholar
Labov, William, Yaeger, Malach, & Steiner, Richard. (1972). A quantitative study of sound change in progress, Vol. 1. Report on National Science Foundation contract NSF-GS-3287. Philadelphia, PA: University of Pennsylvania.Google Scholar
Language and National Origin Group. (2004). Guidelines for the use of language analysis in relation to questions of national origin in refugee cases. International Journal of Speech, Language and the Law, 11 (2), 261266.Google Scholar
Markham, Duncan. (1999). Listeners and disguised voices: The imitation and perception of dialectal accent. Forensic Linguistics, 6 (2), 289299.Google Scholar
Masthoff, Herbert. (1996). A report on a voice disguise experiment. Forensic Linguistics, 3 (1), 160167.Google Scholar
Neuhauser, Sara. (2008). Voice disguise using a foreign accent: Phonetic and linguistic variation. The International Journal of Speech, Language and the Law, 15 (2), 131159.Google Scholar
Nolan, Francis. (2003). A recent voice parade. Forensic Linguistics, 10 (2), 277291.Google Scholar
Patrick, Peter L. (2010). Language variation and LADO (Language Analysis for Determination of Origin). In Zwaan, Karin, Verrips, Maaike, & Muysken, Pieter (eds.), Language and origin: The role of language in European asylum procedures: Linguistic and legal perspectives (pp. 7387). Nijmegen, Netherlands: Wolf Legal.Google Scholar
Payne, Arvilla C. (1976). The acquisition of the phonological system of a second dialect. (unpublished doctoral dissertation). University of Pennsylvania, Philadelphia, PA.Google Scholar
Payne, Arvilla C. (1980). Factors controlling the acquisition of the Philadelphia dialect by out-of-state children. In Labov, William (ed.), Locating language in time and space (pp. 143178). New York, NY: Academic Press.Google Scholar
Perrot, Patrick, Morel, Mathieu, Razik, Joseph, & Chollet, Gérard. (2009). Vocal forgery in forensic sciences. In Sorell, Matthew (ed.), Forensics in telecommunications, information and multimedia (pp. 179185). Berlin, Germany: Springer.Google Scholar
Pollack, Irwin, Pickett, James M., & Sumby, William H. (1954). On the identification of speakers by voice. Journal of the Acoustical Society of America, 26, 403406.CrossRefGoogle Scholar
Preston, Dennis R. (1993). Talking Black and talking White: A study in variety imitation. In Houston Hall, Joan, Doane, Nick, & Ringler, Richard (eds.), English old and new: Studies in language and linguistics in honor of Frederic G. Cassidy (pp. 327355). New York, NY: Garland.Google Scholar
Preston, Dennis R. (1996). Whaddayaknow? The modes of folk linguistic awareness. Language Awareness, 5 (1), 4074.Google Scholar
Purnell, Thomas, Idsardi, William, & Baugh, John. (1999). Perceptual and phonetic experiments on American English dialect identification. Journal of Language and Social Psychology, 18, 1030.CrossRefGoogle Scholar
Queen, Robin. (2013). Gender, sex, sexuality, and sexual identities. In Chambers, J. K. & Schilling, Natalie (eds.), The handbook of language variation and change (2nd ed., pp. 368387). Malden, MA/Oxford, UK: Wiley-Blackwell.CrossRefGoogle Scholar
Rampton, Ben. (2005). Crossing: Language and ethnicity among adolescents. Northampton, MA: St. Jerome.Google Scholar
Rampton, Ben. (2011). From multi-ethnic adolescent “heteroglossia” to “contemporary urban vernaculars.” Language and Communication, 31 (4), 276294.Google Scholar
Reich, Allan, Moll, Kenneth, & Curtis, James. (1976). Effects of selected vocal disguise upon spectrographic speaker identification. Journal of the Acoustical Society of America, 60, 919925.Google Scholar
Rico Sulayes, Antonio. (2012). Quantitative authorship attribution of users of Mexican drug dealing related online forums (Unpublished doctoral dissertation). Georgetown University, Washington, DC.Google Scholar
Rico Sulayes, Antonio. (2009). An experiment in automated linguistic profiling of transcribed speech (Unpublished manuscript). Washington, DC: Georgetown University.Google Scholar
Schilling, Natalie. (2011). Language, gender, and sexuality. In Mesthrie, Raj (ed.), The Cambridge handbook of sociolinguistics (pp. 218237). Cambridge, UK: Cambridge University Press.Google Scholar
Siegel, Jeff. (2010). Second dialect acquisition. Cambridge, UK: Cambridge University Press.Google Scholar
Sjöström, Maria, Eriksson, Erik J., Zetterhol, Elisabeth, & Sullivan, Kirk P. H. (2009). A switch of dialect as disguise. Lund Working Papers in Linguistics, 52, 113116.Google Scholar
Van Bezooijen, Renée, & Gooskens, Charlotte. (1999). Identification of language varieties: The contribution of different linguistic levels. Journal of Language and Social Psychology, 18, 3148.CrossRefGoogle Scholar
Van Bezooijen, Renée, & Ytsma, Johannes. (1999). Accents of Dutch: Personality impression, divergence, and identifiability. Belgian Journal of Linguistics, 13, 105129.CrossRefGoogle Scholar
Watt, Dominic. (2010). The Identification of the individual through speech. In Llamas, Carmen & Watt, Dominic (eds.), Language and identities (pp. 7685). Edinburgh, Scotland: Edinburgh University Press.CrossRefGoogle Scholar
Williams, Angie, Garrett, Peter, & Coupland, Nikolas. (1999). Dialect recognition. In Preston, Dennis R. (ed.), Handbook of perceptual dialectology (pp. 345358). Philadelphia, PA: John Benjamins.Google Scholar
Wolfram, Walt, Hazen, Kirk, & Schilling-Estes, Natalie. (1999). Dialect change and maintenance on the Outer Banks. Publication of the American Dialect Society 81. Tuscaloosa: University of Alabama Press.Google Scholar