A Pentagon study obtained by ABC News finds that a new kind of voice lie detector used by the U.S. military and American police departments is no better than "flipping a coin" in detecting lies.
Until the Pentagon ordered a halt to its use, the Voice Stress Analyzer was being used by military intelligence interrogators at Guantanamo Bay and in Iraq. Several suspected terrorists were released from custody based on the machine's results and former Iraqi deputy prime minister Tariz Aziz was one of the many "high value targets" who were hooked up to the now discredited machine.
A laptop, microphone and software program make up what is called the computer-voice stress analyzer, or CVSA. Used by police departments across the country, this lie detector is a foolproof system to help catch criminals and liars, according to the man behind it.
"Police departments have paid $10,000 per system over the last 18 years and rely on it exclusively for truth verification," said Charles Humble, chairman and CEO of the National Institute for Truth Verification, which sells the CVSA. "We have a remarkable record of success."
But as questions surrounding the scientific validity of the machine and Humble's credentials grow, not everyone agrees that that should be the case .
After Michael Crowe's 12-year-old sister, Stephanie, was found stabbed to death in her bedroom, the Escondido, Calif., police department brought him into the station for questioning and hooked him up to the CVSA in the middle of the night.
From tapes recorded during his questioning, Crowe answered "Yes" when the detective asked, "Is today Thursday?" But when Crowe replied "No" when asked whether he took Stephanie's life, the detective told him that he had failed the test.
"I started to think that, you know, maybe the machine's right, especially when they added on top of it that the machine was getting my subconscious feelings on it, that I could be lying and not even know it," Crowe, now 21, told "Primetime." "They said the machine is more accurate than the polygraph and is the best device for telling the truth, for finding the truth."
Once the detective told him that he had failed the test, Crowe said he began to doubt his own memory and wonder whether he might have killed his sister.
"I didn't want to go to prison, and I just wanted to be out of that room," Crowe recalled. "So my only option was to say, 'Yeah, I guess I did it,' and then hope for the best."
Crowe said the police used the machine to persuade him to confess and then to implicate two of his classmates.
"So I got a knife, and I went into her room, and I stabbed her," Crowe can be heard saying on tapes from his questioning.
But one week before the start of his trial, the police found DNA evidence that led to the real killer, a transient who is now in prison for killing Crowe's sister. The judge denounced both the false confession and Humble's machine.
"I don't believe the instrument was wrong. Now were the examiners wrong? I don't know," Humble replied when asked about the case. "I don't believe I owe Michael Crowe an apology."
But when the Crowe family sued Humble and his company, the National Institute for Truth Verification, the case was settled out of court. During a deposition, a top executive from Humble's company admitted under oath that the machine is not capable of detecting truth or lies.
"This device is nothing more than a prop," said John Palmatier, who earned a doctorate in psychology and who studied the machine for the Michigan State Police Department, where he worked. He said his study along with others found no scientific basis for Humble's claims.
"You could not accurately discriminate between truthful and deceptive subjects using that device," said Palmatier. As to whether the device could be used as a scare tactic, Palmatier answered, "Oh, exactly. Police officers have for years."
In his view, Palmatier said that explains the police endorsements that Humble puts in his promotional materials, citing one case after another solved with the stress-analyzer machine.
Humble said the machine can only really be tested in the field, where he said it has a 98 percent accuracy rate.
"We teach that it's an investigative tool. It's not meant for a detective to go out and get a search warrant or to get an arrest warrant," Humble said.
But that is not exactly what happened in Las Vegas in the case of Vincent Sedgwick, married with a young daughter. He was wrongly charged with rape, which carried a possible life sentence. His arrest warrant was based largely on his supposed failure on a CVSA test.
"I went from shock to anger and a lot of resentment, very bitter toward them for doing that," recounted Sedgwick.
Equally outraged, Lee Gates, the judge in the case, threw out the charges against Sedgwick and harshly criticized the police for relying on a machine that he called scientifically unreliable.
"Not only did they use it for investigative purposes, but they used it as a predicate to get him arrested and to have him charged and brought into the criminal justice system, which I think was the biggest miscarriage of justice," said Gates.
In the promotional videos that Humble uses to sell his machines to American law enforcement, there is no mention of Sedgwick's and Crowe's cases.
"Before you go and ruin a man's life, it's important to verify the allegations of child molest, rape, that sort of thing," Humble said in the video.
Although throughout the video Humble is referred to as Dr. Humble, "Primetime" discovered that he is neither a medical doctor nor has he earned a doctorate from an accredited university.
Instead, the diploma on his office wall, which reads "Doctor of Psychology," is an honorary degree, awarded by a Bible college in Indiana that used to have an office in the strip mall where Humble's first office was located.
Pressed as to whether giving himself the "doctor" title is honest, Humble replied, "I think it is."
Finally, Humble claims his firm sold more than a million dollars worth of his machines to the U.S. military.
Military officials confirmed to "Primetime" that the machines were in use in prisons in Guantanamo Bay in Cuba and Iraq until the Pentagon finally banned them.
Robert Rogalski, deputy undersecretary of defense for counterntelligence, said that an exhaustive Pentagon-ordered study of the stress analyzer, whose results are now being made public, found little or no relationship between the machine's reading and the actual presence or absence of deception and stress.
"We feel we need a greater reliability, just as the report indicated, chance, in other words, flipping a coin," said Rogalski.
He was alarmed to hear about a document from Humble's company that bragged that one of its employees had used the machine in Baghdad to free a number of suspected terrorists.
"It's very troubling," Rogalski said of the document. "How truthful was that result, and if there's a question, then I'm concerned about that." He admitted he is especially concerned about the prospect that some of those suspected terrorists were actual terrorists.
As for Crowe, he said he is still trying to get past the experience of being accused of his sister's murder and being locked up for nine months, in large part because of Humble's machine.
"It's a scare tactic, but it's an expensive one, and it's unfortunate that you have police officers who believe in it," said Crowe of his experience. "Who knows how many mistakes they've made by taking this for faith?"
ABC News' Vic Walter, Joe Rhee and Avni Patel contributed to this report.