Voice technology has a say when the truth counts.

Byline: Bill Bishop The Register-Guard

The mysterious murder of Cottage Grove resident Anita Cantu Lemmon in March brought sheriff's investigators to their usual starting point: the next of kin.

But this time they had a new investigative tool, a Computer Voice Stress Analyzer, or CVSA.

Touted as the next generation lie detector, the device measures inaudible changes in the frequency of a person's voice caused by the body's involuntary response to stress. Theoretically, people can't hide a big lie.

The voice analyzer helped focus the investigation and saved a lot of time, Lane County sheriff's Detective Mike Lamb said.

"It cleared the husband right away," he said.

But, like the polygraph before it, the new technology is a magnet for criticism.

Criminal defense lawyers caution against its possible misuse to prosecute the innocent.

Polygraph experts, and government agencies that are heavily invested in the older technology, churn out studies to discredit voice stress analysis.

The National Academy of Sciences lambasted the entire truth-finding industry in a 2001 report. So many studies are so heavily influenced by vested interests, the academy charged, that their unreliability threatens the credibility of the entire body of research literature on the topic of lie detection.

David Hughes, executive director of the National Institute for Truth Verification, said the "polygraph mafia" is out to kill the voice stress analysis industry because they know it works, is easier to use than a polygraph and is less expensive.

Hughes' institute manufactures the CVSA equipment used by the Lane County sheriff's office, Eugene police, about 1,400 other police agencies and the military. CVSA software is installed in a laptop computer. The person interviewed speaks into a microphone whose signal is converted into charts depicting voice frequencies. Trained examiners read the charts to detect deception.

A tool that works

The concept emerged in the 1970s and has evolved with improved technology. Neither polygraph testing nor voice stress analysis may be admitted as evidence in court because of unreliability. However, both may be used by investigators developing cases.

"This is a tool. We state as strongly as we can that this alone should never be used to make an investigative decision," Hughes said.

Training and proper analysis of the voice charts are critical to accuracy, he said.

"The most important thing we teach people is how to couch the questions," Hughes said. "The difference is night and day."

Criminal defense lawyers agree on that point, and often advise clients to decline to give an interview under voice stress analysis.

"It's another Ouija board that police will use to dupe people into believing the technology is foolproof, which, in truth, it isn't - and the police know it. It's just another way to get some hapless individual to spill the beans on himself," said John Henry Hingson III, an Oregon City lawyer and past president of the National Association of Criminal Defense Lawyers.

The big danger comes when police rely on the machine to reinforce a misguided theory about a case, to "search for the truth as they see it," Hingson said.

"When it happens, it's not malicious. The police think they're doing the right thing," he said. "The problem is sometimes they are wrong."

Eugene defense lawyer Shaun McCrea said that very thing happened to a client she had a few years ago in Josephine County. An officer using a polygraph machine elicited a "confession" from the client, an elderly man with a hearing problem.

McCrea, a past president of the Oregon Criminal Defense Lawyers Association, said she vigorously investigated the case and the charges against her client eventually were dismissed without prosecution.

"The people using it want to believe it. If it says the person is stressed, that is going to convince the cops the person is guilty. The alternative hypothesis goes out the window," McCrea said.

The four Lane County sheriff's detectives who are trained to use voice stress analysis have heard all the criticisms before. Among them, they have 89 years of police experience.

They will arrest no one strictly on the results of a voice analyzer result, said Detective Sgt. Rene Stone. Nor can they use the result to get a search warrant.

"We base all of our investigations on facts. This is a tool to help in our investigations," she said.

To be used properly, someone other than the questioner must examine the voice patterns for signs of deception. That way, the questioner's prejudices and blind spots are taken out of the voice evaluation.

To do that, the voice charts from each interview are posted on a private Web site for other trained investigators to evaluate. Stone's detectives return the favor by evaluating charts for other agencies.

Detective Randy Eschleman said the independent review sometimes turns up deception that the local investigator missed. When an independent reviewer finds deception in an answer - even to a question that seems unrelated to the crime - it may give the local investigator something crucial to ask more questions about.

"There are some pretty good liars out there. You can get sucked into their story," Eschleman said. "When you break the deception, you get to the truth. You're not going to get innocent people telling you things they didn't do."

Investigators don't yell, pound the table or insert trick questions. In fact, the questions are set out in advance with the full knowledge of the person to be questioned, said Detective Ed Collins. The interviews are voluntary and the person being interviewed can stop the process at any time.

Collins said part of the training is realizing the voice stress results are not like fingerprints or DNA.

"It's not forensic science. It's just another tool," Collins said.

So far, it's been a tool that works, he said.

Saving investigators time

In the case of Anita Lemmon's murder, the voice stress analyzer indicated that her husband was not a likely suspect - which saved detectives the time they would have spent confirming that fact in other ways.

Instead, they quickly turned to the next possible suspect, the last person to see Lemmon - her husband's uncle, Jerry Lemmon.

He had already given some inconsistent descriptions when he told police that a man on a motorcycle had driven off with Lemmon the day she disappeared. Detectives already had him on the short list of people they wanted to interview, Lamb said.

Jerry Lemmon agreed to answer some questions with the voice analyzer running. The instrument soon displayed the tell-tale voice profile of a lie. Lamb pointed it out to Lemmon.

`He immediately froze up and said, `I don't want to talk to you anymore.' He basically stomped out,' Lamb said.

Lemmon committed suicide before the investigation could determine exactly what happened to Anita Lemmon.

Other unsolved cases will soon get another effort using the new technology, the detectives said. But they just shake their heads at defense lawyers' suggestions that they would ever gamble their careers by using the new technology to railroad an innocent person. They said they've already passed that test a few times.

For example, Eschleman and Lamb said they are convinced they know two people who committed murder in Lane County six years ago. Both are still free because investigators could not gather enough evidence to arrest them. Both suspects failed polygraph tests about the killing at the time, Lamb said, and voice stress technology would make no difference today.

"It's hard, but sometimes you've got to let it go," Lamb said. "You've got to play by the rules."

CAPTION(S):

The Lane County sheriff's office is among agencies using software that analyzes the voice patterns of suspects for signs of deception.