Forensic phonetics is the application of the knowledge, theories and methods of general phonetics to practical tasks that arise out of a context of police work or the presentation of evidence in court, as well as the development of new, specifically forensic-phonetic, knowledge, theories and methods. (Quoted from Michael Jessen: Language and Linguistics Compass, 2008)
Within the reports voice-comparison compiles, samples of German and Germanic languages are analyzed; analyses from other language families, make up more than half of the case load. For the linguistic analysis of foreign language cases, sworn-in (judicial) interpreters and language specialists are consulted in accordance with the IAFPA Code of Practice, and may contribute to a report.
The majority of recordings are from telephone interceptions.
If the material permits for the use of automatic speaker recognition, voice-comparision uses "VOCALISE" for the analysis, and "Bio-Metrics" for a graphic representation of the results. Automatic speaker recognition can not stand alone in a report. A complete report will be comprised of auditory-acoustic analyses as well as automatic speaker recognition, provided, automatic recognition is possible.
In the following paragraph you find a representative selection of current literature on all the aspects of forensic phonetics research and subsequent expert witness reports.
Jessen, M. (2021): "Speaker profiling and forensic voice comparison: The auditory-acoustic approach",
in Coulthard, M., May, A., Sousa-Silva, R. (eds.) The Routledge Handbook of Forensic Linguistics, second edition. Abingdon, UK: Routledge, 382 - 399.
Gerlach, L., McDougall, K., Kelly, F., Alexander, A. (2020): "Exploring the relationship between voice similarity estimates by listeners and by an automatic speaker recognition system incorporating phonetic features", Speech Communication 124: 85 - 95.
van der Vloed, D., Kelly, F., Alexander, A. (2020): "Exploring the effects of device variability on forensic speaker comparison using VOCALISE and NFI-FRIDA. A forensically realistic database", Proc. Odyssey 2020 The Speaker and Language Recognition Workshop, 402 - 407.
Skarnitzl, R., Asiaee, M., Nourbakhsh, M. (2019): "Tuning the performance of automatic speaker recognition in different conditions: effects of language and simulated voice disguise", International Journal of Speech Language and the Law 26: 209 - 229.
Morrison, G.S. and Enzinger, E. (2019): "Introduction to forensic voice comparison", in Katz, W.F. and Assmann, P. F. (eds.) The Routledge Handbook of Phonetics. Abingdon, UK: Routledge, 599 - 634.
Maher, R.C. (2018): Principles of Forensic Audio Analysis. Cham: Springer.
Morrison, G.S., Sahito, F.H., Jardine, G., Djokic, D. Clavet, S., Berghs, S., Goemans Dorny, C. (2016): "INTERPOL survey of the use of speaker identification by law enforcement agencies", Forensic Science International 263: 92 - 100.