Admission of fMRI Lie Detector “Evidence” Sought

Alexis Madrigal writes for about what is reportedly the first attempt to have fMRI lie detector results admitted in court:

Defense attorneys are for the first time submitting a controversial next-generation lie-detection test as evidence in criminal court.

In an upcoming juvenile-sex-abuse case in San Diego, the defense is hoping to get an fMRI scan, which shows brain activity based on oxygen levels, admitted to prove the abuse didn’t happen.

The technology is used widely in brain research, but hasn’t been fully tested as a lie-detection method. To be admitted into court, any technique has to be “generally accepted” within the scientific community.

The company that did the brain scan, No Lie MRI, claims their test is over 90 percent accurate, but some scientists and lawyers are skeptical.

“The studies so far have been very interesting. I think they deserve further research. But the technology is very new, with very little research support, and no studies done in realistic situations,” Hank Greely, the head of the Center for Law and the Biosciences at Stanford, wrote in an e-mail to

See MRI Lie Detection to Get First Day in Court for the rest of the story.

Sam Harris on True Lie Detection

Neuroscientist Sam Harris answers the Edge Foundation’s annual question for 2009, “What game-changing scientific ideas and developments do you expect to live to see?” with a commentary titled “True Lie Detection.” Excerpt:

When evaluating the social cost of deception, one must consider all of the misdeeds — marital infidelities, Ponzi schemes, premeditated murders, terrorist atrocities, genocides, etc. — that are nurtured and shored-up, at every turn, by lies. Viewed in this wider context, deception commends itself, perhaps even above violence, as the principal enemy of human cooperation. Imagine how our world would change if, when the truth really mattered, it became impossible to lie.

The development of mind-reading technology is in its infancy, of course. But reliable lie-detection will be much easier to achieve than accurate mind reading. Whether on not we ever crack the neural code, enabling us to download a person’s private thoughts, memories, and perceptions without distortion, we will almost surely be able to determine, to a moral certainty, whether a person is representing his thoughts, memories, and perceptions honestly in conversation. Compared to many of the other hypothetical breakthroughs put forward in response to this year’s Edge question, the development of a true lie-detector would represent a very modest advance over what is currently possible through neuroimaging. Once this technology arrives, it will change (almost) everything.

Economist Robin Hanson at the Overcoming Bias blog takes a more skeptical view in his brief commentary, “A World Without Lies?”

A Discussion of fMRI-based Lie Detection

On 3 June 2008, Tom Fudge of San Diego, California radio station KPBS hosted a discussion of fMRI-based lie detection. Guests included No Lie MRI founder and CEO Joel Huizenga, San Diego attorney Chuck Sevilla, and University of San Diego professor of philosophy and ethicist Larry Hinman. The program may be downloaded as a 16 mb MP3 file.

Bioethicist Jonathan Marks Raises Concerns About fMRI-based “Lie Detectors” and Coercive Interrogations

Penn State Live reports on concerns raised by Dr. Jonathan Marks about the premature adoption of fMRI-based lie detectors:

High tech interrogations may promote abuse
Monday, March 17, 2008

University Park, Pa. – There is evidence that brain imaging technology is being used to interrogate suspected terrorists despite concerns that it may not be reliable, and that it might inadvertently promote abuse of detainees, according to a Penn State researcher. He says the risk that such technology could license further abuse of detainees remains ever present, given President Bush’s March 8 veto of legislation that would have prohibited the CIA from conducting aggressive interrogations.

Continue reading Bioethicist Jonathan Marks Raises Concerns About fMRI-based “Lie Detectors” and Coercive Interrogations

Robert Bazell Sheds Light on Lie Detectors

MSNBC chief science and health correspondent Dr. Robert Bazell comments on the U.S. Government’s persistent but misplaced reliance on polygraphy in his “Second Opinion” column:

Shedding light on lies — and lie detectors

Polygraphs persist despite failing science’s truth test

By Robert Bazell

Chief science and health correspondent

updated 9:08 a.m. ET Dec. 4, 2007

Two fascinating spy scandals came to light recently. Both cases illustrate the government’s bizarre reliance on lie detectors, even though sound science finds polygraph tests virtually useless.

Nada Nadim Prouty worked for both the FBI and CIA before an investigation revealed she had lied to get jobs at the two agencies. The probe found that she had obtained her U.S. citizenship illegally, searched the FBI’s restricted computer files on the terrorist organization Hezbollah, and had some relatives who might be affiliated with the group.

Prouty, who was born in Lebanon, was not charged with spying. She pleaded guilty last month in federal court to defrauding the government on the immigration charges. But, as part of the plea deal, she will have to answer questions about the suspicious relatives while hooked up to a polygraph.

The other case involves Rita Chiang, an FBI agent in the bureau’s China section who was forced to suddenly surrender her gun and badge in 2002. The agency believed a mole had compromised the division and suspected Chiang, although it ultimately cleared her and allowed her to return to duty. The mole, it turns out, was the mistress of Chiang’s boss.

As a result, Chiang quit and is now suing the FBI. She alleges that, after the charges were made she lived under such a cloud of suspicion that it was emotionally impossible for her to function.

Why did she come under suspicion in the first place? Apparently she failed a polygraph test.

Despite their common use by the government in these and many other cases — and what you’ve seen in movies and TV detective shows — polygraph machines don’t work very well.

Real world failure
An extensive study from the National Academy of Sciences published in 2003 concluded that in a very controlled setting — say, with college students in a psychology lab — a polygraph can discriminate lying at “rates above chance.”

But the machine — which measures pulse, blood pressure, sweat and other physiological parameters — often fails in the real world. Countermeasures, or ways to cheat the test, are well known and widely available. That’s why the National Academy of Sciences concluded that “polygraph test accuracy may be degraded by countermeasures, particularly when used by major security threats who have a strong incentive and sufficient resources to use them effectively.”

The Academy found that reliance on polygraph testing to screen government employees who may be potential security threats results in “too many loyal employees falsely judged deceptive and too many security threats left undetected.”

Indeed, the histories of the FBI and CIA are replete with spies and double agents who successfully evaded the polygraph.

Illuminating a lie
And, yet, polygraphs persist.

By one estimate, the federal government alone administers 40,000 a year. Evidence from polygraphs cannot be admitted in federal courts; however, some state courts allow them. Many law enforcement agencies rely on the devices to try to coerce confessions.

Polygraphs are big moneymakers for the companies that produce them. But beyond the commercial pressure, we may simply want to believe that scientists have found a magic way to look into the mind and illuminate a lie.

Many people expressed this opinion during a recent opening session of a project on neuroscience and the law, funded by the Macarthur Foundation. The foundation is providing a three-year, $10 million grant for the Law and Neuroscience Project, involving a distinguished group of neuroscientists, legal scholars and bioethicists. They’ll probe questions such as: could brain scans someday be used to find a liar? And what if scientists could find an accurate picture of the criminal mind? Should we screen schoolchildren before they get into trouble?

From what I can see, these applications are far in the future — if they are ever ascertainable.  The problem — as the polygraph shows us — is that lack of scientific proof may not prevent widespread use of other machines that promise to see inside our brains.

MSNBC has also posted a poll that asks the question, “Do you think the U.S. government should continue to use polygraph tests?”

Bill Softky Asks, “Will There Ever Be a Real ‘Lie Detector?'”

Software engineer Bill Softky ponders the question in on-line British technology publication, The Register in his article, “Will There Ever Be a Real ‘Lie Detector?'” Softky begins by dispensing with the delusion that the polygraph can detect lies:

Lie detectors figure prominently in the sauciest dramas, like espionage and murder, but they deeply polarize opinion. They pit pro-polygraph groups like the CIA, the Department of Energy and police forces against America’s National Academy of Sciences, much of the FBI, and now the US Congressional Research Service. The agencies in favor of lie detectors keep their supporting data secret of obfuscated. The critics have marshaled much better arguments.

They have countless earnest references on the site, including an amusing 1941 screed on “How to Beat the Lie Detector”, or an elegant essay in Science Magazine. My favorite: a letter by the convicted CIA double-agent Aldrich Ames – written from prison! – with the authority of someone who kept his traitorous career intact by successfully beating polygraphs time and time again: “Like most junk science that just won’t die… because of the usefulness or profit their practitioners enjoy, the polygraph stays with us,” he wrote.

So it’s clear the old lie detector technology is bunk, pure and simple. Will there ever be a new technology which does in fact detect lies? No, and here’s why….

Softky goes on to discuss such technologies as “brain fingerprinting” (which is specifically not offered as a method of lie detection) and fMRI (which is). He concludes:

The present brand of lie detection still hasn’t proved itself scientifically in seventy years of trying, so it should be shelved before it derails even more careers or mistakenly vets even more spies. The new methods may be better, but we should test them as carefully as we do drugs before we give them an equivalent chance to do serious damage.

Very well said!

Ronald Bailey on Reading Minds

Science correspondent Ronald Bailey reports for Reason magazine on fMRI-based “lie detection” in “Reading Minds: Is Commercial Lie Detection Set to Go?” Excerpt:

Evolutionary psychologists suggest that human cooperation is the result of evolved brain mechanisms that enabled our ancestors to detect cheaters. Broadly speaking, cheaters are people who accept a benefit from someone on the understanding that they will reciprocate, but then fail to give back. A robust finding of game theorists is that the ability to detect cheaters is necessary for cooperation evolved. In the constrained situations that characterize games it’s easy for players to detect cheaters because their lack of reciprocation becomes immediately obvious. But what about the real world? Are evolutionary psychologists right when they claim that human beings have evolved into natural lie detectors?

Most of us think that we’re pretty good at identifying liars. However, a lot of experimental data says that we’re wrong. Most people can distinguish truth from lies at a rate no better than chance. Not even professionals, such as cops and judges, do much better. Of course, humanity has been ceaselessly seeking the fool-proof lie detector, ranging from thumbscrews to polygraph testing. With regard to the latter, the National Academies of Science issued a comprehensive report in 2003 on polygraphy that concluded, “There is essentially no evidence on the incremental validity of polygraph testing, that is, its ability to add predictive value to that which can be achieved by other methods.”

Smithsonian Magazine on Lie Detection

Smithsonian magazine has published in its February 2007 issue an article by Eric Jaffe titled, “Detecting Lies.” Excerpt:

An early form of lie detection existed in India 2,000 years ago. Back then, a potential liar was told to place a grain of rice in his mouth, and chew. If he could spit out the rice, he was telling the truth. If he could not, that meant fear of being caught had parched his throat, and his deceit was confirmed.

Since that time, scientists have searched for a truth tool more reliable than Uncle Ben’s–one that can separate fibs from facts with the push of a button. Such a device could slash trial length, aid job screeners and protect borders. The person to fashion this magical instrument–as precise as DNA, and far more applicable–would shift the entire landscape of forensic discovery. It could create a gap in the dictionary between “periwinkle” and “perk,” where “perjury” once stood, and a crater in the TV Guide, where “CSI” and all its spin-offs once reigned supreme.

But each advance in the field of lie detection has met with a hitch. Polygraph machines have drawn considerable scientific scrutiny and remain inadmissible in courtrooms. Functional imaging has pinpointed which areas of the brain become active when people lie, but the results are based on group averages and become less accurate when a single person is tested. Even people with incredibly accurate facial analysis skills, so-called lie detection “wizards,” were called into question last month in the journal Law and Human Behavior.

What follows is an overview of the long and continued struggle to find the perfect lie detector.

The Polygraph

In the early 20th century, Harvard psychologist William Mouton Marston created his “systolic blood pressure test,” more commonly known as the polygraph machine. Marston’s hodgepodge of gizmos included a rubber tube and a sphygmomanometer–that childhood favorite the pediatrician wraps around a bicep and inflates with each squeeze of an egg-shaped ball. Polygraph 101 is clear enough: a person has typical levels of heart-rate, respiration and blood pressure when answering a basic question like “Is it true you live at 520 Elm Street?” If these levels remain the same during questions such as “Did you kill Jane Doe?” then the person is telling the truth. If not, he or she is lying.

Despite its reputation as the default lie detector, the polygraph has never received much credibility. In 1922, a federal judge ruled that Marston’s device could not be used in a murder case; it did not hold “general acceptance” among the scientific community, wrote Justice Josiah Alexander Van Orsdel of the United States Court of Appeals. This decision, known as the “Frye standard,” has essentially kept the polygraph out of courtrooms ever since.

In 2002, the National Academy of Sciences orchestrated a massive review of the polygraph. The Academy concluded that the tool was not consistent enough to be used as a screening device when hiring national security employees. The physiological responses measured by the machine can be the result of many factors other than lying, including mere nervousness.

“There are many people who will speak in favor of the polygraph,” says William Iacono, who is a professor of psychology and law at the University of Minnesota. “The argument is, if the government uses it 100,000 times a year, how can it be so wrong? The reason they believe it is because of the nature of the feedback they get. Occasionally, people fail the test and they’re asked to confess, and they do. But if a guilty person passes, he doesn’t turn around on his way out and say: ‘Hey, I really did it.’ They never learn of their errors, so they don’t think there are any errors.”

In the end, Marston’s reputation made out better than that of his machine; he went on to earn fame as the creator of Wonder Woman.

Jaffe goes on to discuss the Guilty Knowledge Test, P300, fMRI, and so-called lie detection “wizards.”