Biometrics and Forensics: from speaker recognition to forensic speaker recognition and forensic biometrics

Prof. Andrzej Drygajlo
Swiss Federal Institute of Technology at Lausanne (EPFL), Switzerland

Biometrics is the science of establishing the identity of individuals based on their biological and behavioural characteristics. Forensic science refers to the applications of scientific principles and technical methods to the investigation of criminal activities, in order to demonstrate the existence of a crime, and to determine the identity of its author(s) and their modus operandi.

This lecture will focus on development of automatic systems for forensic speaker recognition (FSR) based on scientifically approved methods for calculation and interpretation of forensic evidence and validated on databases recorded in real-life conditions.

The ongoing paradigm shift in the forensic automatic speaker recognition involves biometric methods for the calculation of the evidence value, its strength and the evaluation of this strength under operating conditions of the casework. In such methods, the biometric evidence consists of the quantified degree of similarity between speaker-dependent features extracted from the trace (questioned voice recording) and speaker-dependent features extracted from recorded speech of a suspect, represented by his/her model.

This lecture aims at implementing deterministic and statistical automatic speaker recognition (ASR) methods that provide several ways of quantifying and presenting recorded voice as biometric evidence, as well as the assessment of its strength (likelihood ratio) in the Bayesian interpretation framework, including scoring and direct methods, compatible with interpretations in other forensic disciplines. The lecture will conclude with adaptation of the Bayesian interpretation of biometric evidence as implemented in the forensic automatic speaker recognition to the forensic biometrics domain, in general.





Technical Committee on Biometrics (TC4)




European Association for Signal Processing




EAB European Association for Biometrics




University of Sassari