“Could Your Voice Betray You?”

Douglas Heingartner reports for the New York Times. Excerpt:

IT is a time-honored interrogation tool and a staple of film noir: the lie-detector test that can incriminate or exonerate.

But such tests need not involve strapping someone to a machine. In fact, they may not require the subject’s presence – or awareness – at all. And their use is growing far beyond criminal investigations.

Increasingly, lie-detector tests use voice stress analysis, a technology that has been around for decades but that has gained in popularity as the software at its heart continues to be refined.

“It can really be done anywhere,” said Detective Pat Kemper of the Springfield Township Police Department in Ohio, who says he has used the voice-based testing to question thousands of suspects over the last decade. “It can be done via a telephone recording. It can be done covertly. You can use it for anything.”

Indeed, beyond its applications in law enforcement, proponents of the voice-based technology see its utility in everything from telemarketing to matchmaking. In Britain, a growing number of insurance companies have been using it to screen telephone claims in hopes of rooting out fraud – a goal they say has been borne out, both in fraud detection and in deterrence. One insurer, Admiral, says 25 percent of its car-theft claims have been withdrawn since it began using the system a year ago.

But the technology’s reliability is still a matter of debate, and its migration from the interrogation room to the call center has raised concerns about potential privacy implications. Voice analysis of this nature, after all, can easily be conducted without the speaker’s knowledge. Now that it is being used in the insurance industry, for example, the concerns include how a suspect claim might affect a customer’s subsequent applications for insurance.

The makers of one system, known as the Computer Voice Stress Analyzer, try to address such worries by controlling access to the technology. “We only sell to law enforcement and the government,” said David Hughes, executive director of the National Institute for Truth Verification, the company selling the system.

The analyzer has been available since 1988, and the company says it is used by over 1,400 law enforcement agencies across the United States, as well as by other state and federal agencies including the Defense Department. “In private industry, you’re doing it for profit, so there’s always a concern about ethics violations,” Mr. Hughes said. “You can’t be cavalier.”

But that distinction does not appease everyone. “Government is not necessarily more responsible than private industry,” said Bob Barr, a former congressman from Georgia who is a privacy consultant for several organizations. “The government can put you in jail if it doesn’t like what it finds.”

Actually, the reliability of voice stress analysis is not a matter of debate amongst scientists. The claims of voice stress analysis proponents are entirely unsupported by any peer-reviewed research whatsoever.

“Police Use of Voice Stress Analysis Generates Controversy”

Margie Wylie reports for the Newhouse News Service in a well-researched article on CVSA. Excerpt:

Police departments across the country are buying the controversial Computer Voice Stress Analyzer, which its manufacturer claims can tell when a person is lying merely by the sound of his voice. When a suspect speaks, a computer program “listens” for minute vocal shifts that, in theory, indicate stress.

The technology’s critics, citing government and university research, say the CVSA is little more than an electronic Ouija board with accuracy rates to match. At best, they say, voice stress analysis scares suspects into confessions; at worst, it can incriminate the innocent.

CVSA results aren’t admissible in most courts, under the same Supreme Court decisions that generally bar polygraph evidence.

Even so, police officers love it. Cheaper and faster than the polygraph, the CVSA can be operated with a few days’ training and without the need to “wire up” a suspect. It can also be used in the field, covertly, and on tape recordings, according to the National Institute for Truth Verification of West Palm Beach, Fla., its manufacturer.

Between 1999 and 2000, NITV added 100 new customers. So far in 2001, NITV officials say nearly 300 police departments have bought at least one CVSA. Some have bought several, and nearly all “have put their polygraph on the shelf,” said David Hughes, a retired police captain and executive director of the company.

Originating from a Cold War military project, voice stress analysis was first commercialized in the early 1970s.

NITV, founded in 1986, has a virtual lock on the law-enforcement market,according to both the company and its critics. It has sold its $10,000 CVSA to more than 1,100 police departments and trained more than 4,200 CVSA operators at about $1,300 each, Hughes said.

The company’s Web site is replete with testimonials and success stories. One Alabama police department is said to have solved a murder case 14 years cold by re-interviewing the main suspect with the CVSA. The suspect had previously taken four polygraphs given by three different examiners, all inconclusive. Confronted with three failed voice stress tests, he broke down and confessed.

Researchers counter that nothing in 30 years of studies proves that voice stress analysis works, either generally or in the specific case of the CVSA.

“Voice stress analysis is a fraud. It has zero validity,” said David T. Lykken, a psychology professor emeritus at the University of Minnesota in Minneapolis and author of the book “A Tremor in the Blood: Uses and Abuses of the Lie Detector.”

For discussion of CVSA, see the CVSA forum on the AntiPolygraph.org message board.