NCJ Number
56186
Date Published
1977
Length
12 pages
Annotation
THE USE OF VOICE PRINT IDENTIFICATION AS EVIDENCE IS DISCUSSED AND CRITICIZED, WITH ATTENTION TO THE DYNAMICS OF THE TECHNIQUE, THE ROLE OF TECHNICIANS, AND REASONS FOR THE APPARENT ACCEPTANCE OF VOICE PRINTS AS EVIDENCE.
Abstract
THE USE OF THE VOICE PRINT TECHNIQUE TO IDENTIFY INDIVIDUALS FROM THEIR SPEECH IS CREATING SUBSTANTIAL CONTROVERSY IN THE U.S. THE APPARENT SUCCESS OF THIS METHOD OF SPEAKER IDENTIFICATION RESULTS FROM A NUMBER OF RELATIONSHIPS OR CONDITIONS: (1) THE PROPONENTS OF VOICE PRINTS ARE RARELY OPPOSED IN THE COURTS, (2) THEY CLAIM THEIR METHOD MEETS THE FRYE TEST (I.E., THAT THE SCIENTIFIC COMMUNITY ACCEPTS VOICE PRINTS), (3) THEY CLAIM THE METHOD WORKS BECAUSE OF THE UNIQUENESS OF AN INDIVIDUAL'S SPEECH AND BECAUSE INTERSPEAKER VARIABILITY IS ALWAYS GREATER THAN INTRASPEAKER VARIABILITY, AND (4) THEY CLAIM THAT THE RESEARCH THEY HAVE CARRIED OUT DEMONSTRATES THE RELIABILITY OF THE TECHNIQUE AND THAT VOICE PRINT EXAMINERS CAN CORRECTLY EXERCISE THE METHOD. HOWEVER, THE AURAL/PERCEPTUAL PROCESS OF SPEAKER IDENTIFICATION IS FAR MORE COMPLEX THAN IS COMMONLY UNDERSTOOD AND THE RESEARCH THAT HAS BEEN CARRIED OUT SUGGESTS THAT IT IS A PROCESS THAT CAN RESULT IN UNACCEPTABLE ERRORS, ESPECIALLY UNDER THE CONDITIONS OF ADVERSE LISTENING OFTEN FOUND IN THE FORENSIC SITUATION. FURTHER, DUE TO THEIR RELATIONSHIP TO THE PROCESS, THE OBJECTIVITY OF EXAMINERS MAY BE AS SUSPECT AS THEIR TRAINING REQUIREMENTS, WHICH SEEM INADEQUATE GIVEN THE IMPORTANCE OF THE EVIDENTIARY FUNCTION THEY ARE ASKED TO PERFORM. UNLIKE SPEAKER VERIFICATION, THE SPEAKER IDENTIFICATION PROCESS FACES SUBSTANTIAL DIFFICULTIES BOTH FROM THE INDIVIDUALS TO BE IDENTIFIED AND THE MILIEU IN WHICH THEY ARE SPEAKING, AND IT SHOULD BE STRESSED THAT NONE OF THE INDIVIDUALS OR GROUPS THAT ARE DEVELOPING SPEAKER IDENTIFICATION SYSTEMS ARE PROPOSING THAT THEIR APPROACHES BE UTILIZED IN THE INVESTIGATORY SITUATION OR IN THE COURTS. REFERENCES ARE FOOTNOTED. (KBL)