Could Your Voice Betray You?
By DOUGLAS HEINGARTNER

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 One insurer, Admiral, says 25 percent of its car-theft claims have been withdrawn since it began using the system a year ago.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.