The articles are very dated and as noted by another poster, relate to witness identification of a voice. I think your info was more recent and discusses spectrogram use for voice analysis. I can see that being useful to detect stress levels.
The new technologies built by Amazon, Google, Meta, Apple will, IMO, undoubtedly change the course of investigations and eventually be used in criminal proceedings.
I’m reading this more recent piece (2020) about voiceprint identification. Indiana appears not to allow it. Yet!
“Many state and federal courts have abandoned Frye and adopted the argument of McCormick. The supreme courts of Minnesota, Maine, Ohio and Rhode Island have admitted aural-spectrographic voice evidence following McCormick. Intermediate appellate courts in California, Mary land and Michigan admitted such evidence following Frye but were reversed by their respective supreme courts, which held that the Frye test had not been met. The Massachusetts Supreme Court held aural-spectrographic voice evidence admissible applying the Frye test,
while those of Arizona, Indiana and Pennsylvania did not.”
Voiceprint identification can be defined as a combination of both aural (listening) and spectrographic (instrumental) comparison of one or more known voices with an unknown voice
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