Speaker-individuality in suprasegmental temporal features: Implications for forensic voice comparison

Everyday experience tells us that it is often possible to identify a familiar speaker solely by his/her voice. Such observations reveal that speakers carry individual features in their voices. The present study examines how suprasegmental temporal features contribute to speaker-individuality. Based on data of a homogeneous group of Zurich German speakers, we conducted an experiment that included speaking style variability (spontaneous vs. read speech) and channel variability (high-quality vs. mobile phone-transmitted speech), both of which are characteristic of forensic casework. Speakers demonstrated high between-speaker variability in both read and spontaneous speech, and low within-speaker variability across the two speaking styles. Results further revealed that distortions of the type introduced by mobile telephony had little effect on suprasegmental temporal characteristics. Given this evidence of speaker-individuality, we discuss suprasegmental temporal features’ potential for forensic voice comparison.