How we use automatic speaker comparison in forensic practice

Authors

  • David van der Vloed Netherlands Forensic Institute
  • Tina Cambier-Langeveld Netherlands Forensic Institute

DOI:

https://doi.org/10.1558/ijsll.23955

Keywords:

automatic speaker recognition, automatic speaker comparison, forensic speaker comparison, forensic speaker recognition, court communication, forensic casework, explanatory note

Abstract

Automatic methods are rapidly gaining ground in forensic speaker comparison, next to the existing auditory-acoustic methodology, performed by human experts with an academic background in phonetics. In this article we set out the steps that were taken before we could introduce the automatic method and start combining the two methods (software and human) in casework. We further provide a comprehensive explanation of the automatic method (originally written for readers of forensic reports) in the appendix. We discuss the legal reception of the combined approach, based on a court ruling in an appeal case in which the reliability of the speaker comparison was challenged by the defence. We also address the important issue of how conflicting results from the two methods may be dealt with in practice.

Author Biographies

  • David van der Vloed, Netherlands Forensic Institute

    D.L. (David) van der Vloed MA is a forensic speech researcher at the Netherlands Forensic Institute (NFI) and has a background in phonetics and sociolinguistics. He has worked on hundreds of cases in over 13 years. He built the NFI-FRITS and NFI-FRIDA collections, each containing a set of forensically realistic data. With those, he performed validation research on automatic speaker recognition methods, which resulted in implementation of automatic speaker recognition in NFI casework in 2019.

  • Tina Cambier-Langeveld, Netherlands Forensic Institute

    Dr Tina Cambier-Langeveld holds a PhD in phonetics. She was trained as a forensic phonetician at the Netherlands Forensic Institute (NFI). She is now an instructor and consultant for the speech group at the NFI, and fills the position of senior linguist at the Dutch immigration service. She teaches an MA course on forensic speech science at Leiden University. She is President of the International Association for Forensic Phonetics and Acoustics.

References

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van der Vloed, D., Bouten, J. and van Leeuwen, D. A. (2014) NFI-FRITS: A forensic speaker recognition database and some first experiments. Proceedings of Odyssey 2014: The Speaker and Language Recognition Workshop 6–13. Joensuu, Finland: Odyssey. https://doi.org/10.21437/Odyssey.2014-2

van der Vloed, D., Kelly, F. and Alexander, A. (2020) Exploring the effects of device variability on forensic speaker comparison using VOCALISE and NFI-FRIDA, a forensically realistic database. Proceedings of Odyssey 2020: The Speaker and Language Recognition Workshop. Tokyo: Odyssey. https://doi.org/10.21437/Odyssey.2020-57

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Published

2023-04-14

Issue

Section

Professional Practice Reports

How to Cite

van der Vloed, D., & Cambier-Langeveld, T. (2023). How we use automatic speaker comparison in forensic practice. International Journal of Speech, Language and the Law, 29(2), 201-224. https://doi.org/10.1558/ijsll.23955