FEDS VOICE DOUBTS ABOUT VOICE ANALYSIS

• NCJ Number: 59678
• Journal: Police Magazine Volume: 2 Issue: 5 Dated: (SEPTEMBER 1979) Pages: 63-67
• Author(s): D B MOSKOWITZ
• Date Published: 1979
• Length: 5 pages
• Corporate Author: Criminal Justice Publications, Inc
• Publication Format: Article
• Language: English
• Country: United States of America

Annotation

THE STATUS OF THE VOICE SPECTROGRAPH AS A FORENSIC TOOL FOLLOWING PUBLICATION OF A REPORT SERIOUSLY QUESTIONING THE RELIABILITY OF VOICE ANALYSIS IS ASSESSED.

Abstract

VOICE ANALYSIS IS USED MOST OFTEN IN CASES INVOLVING WIRETAPPING--ORGANIZED CRIME, NARCOTICS, KIDNAPPING, EXTORTION. TAPE RECORDINGS OF AN UNKNOWN SUSPECT'S VOICE AND OF A KNOWN SPEAKER'S VOICE ARE FED INTO A SOUND SPECTROGRAPH, WHICH PRODUCES 'VOICEGRAMS' THAT MAY BE COMPARED FOR SIMILARITIES. THE FBI COMMISSIONED THE NATIONAL RESEARCH COUNCIL (NRC) OF THE NATIONAL ACADEMIES OF SCIENCES AND ENGINEERING TO EVALUATE THE VOICE SPECTROGRAPH. THE NRC STUDY CONCLUDED THAT THE TECHNICAL UNCERTAINTIES OF VOICE IDENTIFICATION ARE SUCH THAT FORENSIC APPLICATIONS SHOULD BE APPROACHED WITH GREAT CAUTION. THE STUDY ALSO CONCLUDED THAT, IF COMPARISONS OF VOICEGRAMS ARE ADMITTED AS EVIDENCE IN TRIALS, THEN THE LIMITATIONS OF THE TECHNIQUE SHOULD BE MADE CLEAR TO THE JUDGE AND JURY. THE REPORT DID NOT DISMISS THE IDEA OF USING VOICE ANALYSIS IN POLICE WORK, BUT ITS OVERALL SKEPTICISM APPEARS TO HAVE DISSUADED SOME POLICE AGENCIES FROM PURCHASING VOICE SPECTROGRAPH EQUIPMENT. MUCH OF THE VOICE ANALYSIS WORK OF POLICE AGENCIES IS PERFORMED BY THE MICHIGAN STATE POLICE, WHICH PIONEERED THE TECHNIQUE AND ACCEPTS REFERRALS FROM OTHER AGENCIES. THE HEAD OF THE NEW YORK CITY VOICE IDENTIFICATION UNIT FEELS THAT THE TECHNIQUE IS MOST VALUABLE AS A MEANS OF SCREENING SUSPECTS. CONSIDERABLE RESEARCH HAS BEEN CONDUCTED ON THE ACCURACY OF VOICEGRAM MATCHES, WITH VARYING RESULTS. ONE PROBLEM HAS BEEN THAT VOICE ANALYSIS LACKS THEORETICAL UNDERPINNING--KNOWLEDGE OF WHY ONE PERSON'S VOICE PATTERNS DIFFER FROM ANOTHER'S, OR OF WHY SPEAKERS SOUND DIFFERENT AT DIFFERENT TIMES. SOME COURTS HAVE ACCEPTED VOICEGRAMS AS EVIDENCE, WHILE OTHERS HAVE NOT. THE NRC REPORT IS LIKELY TO BE USED BY DEFENSE ATTORNEYS TO DEFEAT PROSECUTION ATTEMPTS TO INTRODUCE VOICEGRAMS IN TRIALS. (LKM)