posted 01-03-2008 09:19 AM            

Voice stress analyzer may challenge polygraph

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Wednesday, January 02, 2008
BY JOHN BRANTON, Columbian staff writer

Maggi Holbrook has heard about the Computer Voice Stress Analyzer but hasn't seen one yet.

"I thought, 'Boy, that would be a cool thing,' " said Holbrook, a computer forensics investigator with the Vancouver Police Department who goes after cyber-stalkers who target children.

"I can think of a few people I'd like to plug into it."

The system's maker and seller, the National Institute for Truth Verification, says its several models outperform the polygraph by sensing stress in a guilty person's voice.

Used by more than 1,700 law enforcement agencies and the U.S. military, the systems have been used to solve murders, rapes and many other crimes, the institute says.

The institute says its CVSAs use advanced mathematical algorithms, some patented, and a built-in learning feature to evaluate voice patterns.

The devices score and graph voices for stress levels - and conclude whether any deception was indicated.

The latest version, the CVSA II, starts at $9,995, including the Dell Latitude D620 laptop computer it's installed in.

For the military, there's a handheld 1-GHz, 30-GB Field Interrogation Support Tool for the same price.

And $12,999 buys the CVSA II Panasonic Toughbook 29 that "will handle the most demanding conditions such as desert, jungle, naval and combat operations."

As Holbrook said: cool, if it works.

We all love the truth, right?

For now, moms and dads, teachers and kids needn't get their hopes up of buying one - but your boss might.

Formerly available only to law enforcement, the devices now are sold for some commercial applications. The institute says it's sold more than 650 model IIs since their release early in 2007.

A December 2005 story in The American Spectator, posted on the institute's Web site, www.nitv1.com , says the technology of analyzing voice stress began in the 1960s, developed by retired Army officers who wanted something more versatile than the polygraph.

The story adds that, though the devices in 2005 were used by more than 1,000 law enforcement agencies, not everyone is convinced of their value.

Based in West Palm Beach, Fla., and started in 1988, the institute says its CVSAs are "regarded as a threat by the entrenched polygraph establishment as it displaces both them and their technology."

As with polygraph evidence, that from CVSAs normally isn't used in court.

In case studies described by the institute, it says police have used the devices to rule out innocent suspects - and have obtained confessions after showing suspects the analyses of their voices.

Even cell phone callers have been successfully tested, the institute says, as have tape-recorded statements made by a suspect six years before a CVSA was used.

Fourteen years after a man murdered his sister-in-law, the institute says, a CVSA test showed deception and led to a confession and recovery of the body.

Did you know?

Traditional polygraph lie detectors work by measuring a person's heart rate, blood pressure, respiratory rate and electro-dermal activity (sweatiness, in this case of the fingers) change in comparison to normal levels.

New Mexico is the only state in the United States that allows for open admissibility of polygraph exam results. Every other state requires some type of stipulation to be met prior to admitting polygraph exams into record.

Source: How Things Work

posted 01-04-2008 09:24 AM            

Below is a reply to an e-mail I sent to John Branton (the reporter who wrote the piece). He apparently had no idea of the contraversy surrounding CVSA.

Liedoctor...

Thu, 03 Jan 2008 21:44:19 -0800
From: "John Branton"
To: liedoctor@yahoo.com
CC: "John Branton"
Subject: Re: CVSA admits in court that Voice Stress Machine is NOT capable of lie detection

Hi Liedoctor. Looks like this is way more controversial than I knew. I'd left messages for several officers and agents, but they didn't get back before story ran, due to holidays. I'll hold onto your e-mail for a possible future story. Thanks for sending this.

John Branton

>>> liedoctor@yahoo.com 1/3/2008 9:34:52 AM >>>

Mr. Branton,

You may wish to reconsider the unconditional support you provided to voice stress analysis once you read the article below:

"Voice analyzers draw praise, flak

by John Tuohy

Indianapolis Star

November 7, 2004 - Police departments across Indiana and the country are spending thousands of dollars apiece on a truth verification device that some scientists say doesn't work. The Computer Voice Stress Analyzer, designed by a former Indianapolis
Police Department officer, claims to help officers assess truthfulness by measuring changes in one's voice.

Eighty-five Indiana police departments, including IPD, use the machines, which start at $10,700 each.

The designer, Charles Humble, now is chairman and CEO of the National Institute for Truth Verification, which makes the machines. In its literature, the Palm
Beach, Fla., company touts it as "a very reliable investigative tool for verifying statements of witnesses, denials of suspects and for determining the validity of allegations made against police officers."

But several scientific experiments have shown the machine, which went on the market in 1988, is no more than 50 percent reliable -- in other words, a coin toss.

In addition, the manufacturer conceded in a product liability lawsuit in California that the machine can't measure whether someone is lying.

But more than 1,400 police departments nationwide have bought them and paid to train their officers to use them.

Last summer, 25 officers attended a six-day training seminar at IPD's police academy put on by the machine's manufacturer. David Hughes, executive director for the company, said more than 5,000 officers nationwide have been trained to assess the machine's findings.

"If these don't work, why do so many police
departments use them?" he asked.

Doesn't work, critics say

In a 2003 study, the National Academy of Sciences concluded there was no evidence the machines detect lying.

"This research and the few controlled tests conducted over the past decade offer little or no scientific basis for the use of the Computer Voice Stress Analyzer or similar voice measurement instruments as an alternative to the polygraph for the detection of deception," the academy found.

Frank Horvath, a professor of criminal justice at Michigan State University, said about 25 studies have "shown that these devices have no merit whatsoever."

While polygraphs measure three biological reactions --changes in pulse, heart rate and body perspiration -- the voice test records only changes in voice -- so-called "microtremors" in the larynx.

By measuring only one response, voice tests would appear easier to fool than the lie detector, Horvath said.

"It's very easy to change one's voice," he said. There is no proof microtremors exist, he added, and "even if they do, how can it be shown that they relate to stress or deception?"

Polygraph accuracy ranges from 70 percent to 90 percent -- not enough to be admissible in court, but better than voice tests.

Police say the reliability of the voice machines is secondary. They like them because they're a valuable tool in getting confessions.

"It is a big psychological boost for us," said Lt. Joe Mason, an IPD detective. IPD has four machines and about 15 officers trained to use them.

"Is it accurate? Who knows? Is it admissible in court? No. Is a polygraph admissible? No."

Mason said all four machines have been donated to IPD, and most of his officers train for free when IPD hosts the seminars.

Voice analyzers have several advantages over polygraph machines, backers say, including:

* The tests are portable. Polygraphs require several wires be hooked up to a person; voice tests need only a microphone.

* Voice tests can be given on the spot. Detectives sometimes must wait several days to give a polygraph exam because police departments have few trained examiners.

* They can elicit confessions from suspects even before they are administered because of the perception that they work.

A useful tool, others argue

Advocates of voice machines stress that polygraph tests have been around so long that many people know how to fool them.

"Some guys agree to take a polygraph because they know they'll beat it and walk out right away," Mason said.

"You can go anywhere on the Internet and read how to beat it," Hughes said.

The Web site for the voice machine's manufacturer carries dozens of testimonials from police chiefs and detectives crediting the tests with prompting confessions.

Humble said much of the opposition to the test comes from polygraph examiners protecting their turf. And, he said, the academics who criticize it have never
worked with the machine.

"You can listen to a professor at IU, who has never even seen one, spout off about it -- or you can talk to police in the field who are trained and know how it works," Humble said.

Hughes said tests on the analyzers have been flawed because they haven't measured people in real-world circumstances.

Researchers disagree.

"These are complete nonsense and dangerous," said Richard Ofshe, a professor at the University of California-Berkeley and a leading expert on police interrogations. "Any detective should know these aren't reliable. If they don't, they're incompetent."

Some observers say it is unethical for police to promote the tests as accurate.

"This seems like it could be part of a disturbing trend in cases in which it is ruled that police trickery is acceptable," said David Cook, chief public defender in Marion County.

In San Diego, murder charges were dropped against two teenagers after it was determined their confessions were coerced after they flunked voice stress tests.

One of the boys sued the National Institute for Truth Verification, claiming the analyzer was used to get the false confession.

In a court filing, the manufacturer said: "NITV acknowledges that the CVSA is not capable of lie detection and specifically cautions its users
regarding the proper use of the device."

Humble, a trained polygraph examiner, said his company doesn't claim the machine detects lies.

"There is no such thing as a lie detector," he said. "These are stress monitors. This is an investigative tool. It helps guide the way."

But, countered Ofshe, flunking the stress tests breaks the spirit of innocent suspects.

"The operator hypes that these are infallible, and the innocent person is banking on vindication by taking the test," he said.

"When they are told they failed after putting so much faith in them, they falsely confess to get a good deal."

Call Star reporter John Tuohy at (317) 444-6418. JOHN.TUOHY@INDYSTAR.COM"

--------------------------------

In comparison, polygraph testing has through numerous studies, consistantly detected deception at accuracy levels "Signicantly above chance" (National Academy of
Sciences Report)

posted 01-04-2008 10:13 AM            

------------------
"This is our hill and these are our beans."----
Leslie Nielsen as Lt. Frank Drebin, Naked Gun 1988

posted 01-04-2008 02:31 PM            

Assembly Committee on Commerce and Labor March 30, 2007

Ronald Sailon, Assistant City Attorney, Henderson, Nevada: I argued a significant case before the Ninth Circuit Court of Appeals and will summarize the case facts. One of our officers was investigating a rape case. He interviewed the rape suspect using Computer Voice Stress Analysis (CVSA). The results of the CVSA indicated that the suspect was lying to the officer. The officer included the results of the CVSA in his affidavit for arrest. Ultimately, the suspect was acquitted of the rape charge. He sued the officer, the City of Henderson, and the manufacturer of the CVSA.

This case is old and I have submitted a copy of the appellate brief (Exhibit N). He contended that CVSA is "junk science" and that it was improper to use it to establish probable cause to make the arrest. I represented the City of Henderson and the officer in the litigation.

As it progressed, the CVSA manufacturer turned against us and said the officer was wrong to use the CVSA and that the officer had been trained by the manufacturer not to use the results in an affidavit for arrest. This took us completely off-guard. It is an elementary principle of law enforcement that an officer doing an investigation has to include all of the pertinent information summarizing the investigation. The judge decides whether there is probable cause to make the arrest. To say that a person should use this tool as part of his investigation, but not tell the judge about it in the affidavit of arrest, was hardly a position we expected.

Ultimately, the City of Henderson and the Police Officer prevailed. We had a very bitter experience with the CVSA. As the result of this lawsuit, we made the decision never to use it again and have not. If you are going to use the tool, you are going to have to account for it. It is a little disingenuous to have the manufacturer of the CVSA tell us this is a wonderful product and is on par with polygraphs, but do not tell the judge that you used it when you submit an affidavit for arrest.

Assemblyman Horne: ...I think there is more than a procedural issue at stake here. The manufacturer of the CVSA filed an affidavit in court and stated they told the officer not to use the CVSA results in an affidavit and he did it anyway. Why would the manufacturer who would vouch for the validity of his product tell us not to use it? From the legal perspective at the time of this case, it was well established that polygraphs were legitimate law enforcement tools and could be used to establish probable cause. There is no comparable case law with the CVSA, but the manufacturer is telling us not use it to establish probable cause.

Ronald Sailon: That is correct. My advice to the City of Henderson will be to never use this because it is nothing but trouble. If another agency decides to use it, that is their choice. They should look at the background before they take that leap

Liedoctor...