Brain Scans May Be Used As Lie Detectors
By MALCOLM RITTER, AP Science Writer
Picture this: Your boss is threatening to fire you because he thinks
you stole company property. He doesn't believe your denials. The
lawyer suggests you deny it one more time -- in a brain scanner that
will show you're telling the truth, or lying.
Wacky? Science fiction? It might happen this summer.
Just the other day I lay flat on my back as a scanner probed the
tiniest crevices of my brain and a computer screen asked, "Did you
take the watch?"
The lab I was visiting recently reported catching lies with 90 percent
accuracy. And an entrepreneur in Massachusetts is hoping to
commercialize the system in the coming months, hopefully by this summer.
"I'd use it tomorrow in virtually every criminal and civil case on my
desk" to check up on the truthfulness of clients, said attorney Robert
Shapiro, best known for defending O.J. Simpson against murder charges.
Shapiro serves as an adviser to entrepreneur Steven Laken and has a
financial interest in Cephos Corp., which Laken founded to
commercialize the brain-scanning work being done at the Medical
University of South Carolina.
That's where I had my brain-scan interrogation. But this lab isn't
alone. Researchers at the University of Pennsylvania have also
reported impressive accuracy through brain-scanning
recently. California entrepreneur Joel T. Huizenga plans to use that
work to start offering lie-detecting services in Philadelphia this
His outfit, No Lie MRI Inc., will serve government agencies and
"anybody that wants to demonstrate that they're telling the truth," he
said. "Justice Department and FBI have just signed up with us. Their
intention is to use it 'routinely' as part of investigations."
Both labs use brain-scanning technology called functional magnetic
resonance imaging, or fMRI. It's a standard tool for studying the
brain, but research into using it to detect lies is still in early
stages. Nobody really knows yet whether it will prove more accurate
than polygraphs, which measure things like blood pressure and
breathing rate to look for emotional signals of lying; the federal
government hopes it will work as intended.
Advocates for fMRI say it has the potential to be more accurate,
because it zeros in on the source of lying, the brain, rather than
using indirect measures. So it may someday provide lawyers with
something polygraphs can't: legal evidence of truth-telling that's
widely admissible in court. (Courts generally regard polygraph results
as unreliable, and either prohibit such evidence or allow it only if
both sides in a case agree to let it in.)
Laken said he's aiming to offer the fMRI service for use in situations
like libel, slander and fraud where it's one person's word against
another, and perhaps in employee screening by government agencies.
Attornies suggest it would be more useful in civil than most criminal
cases, he said.
Of course, there's no telling where the general approach might lead. A
law review article has discussed the legality of using fMRI to
interrogate foreigners in U.S. custody. Maybe police will use it as an
interrogation tool, too, or perhaps major companies will find it a
cheaper than litigation or arbitration when an employee is accused of
stealing something important, other observers say. Homeland Security
says it can be used to also detirmine how patriotic and loyal (or not)
someone is to the United States.
For his part, Shapiro says he'd switch to fMRI from polygraph for
screening certain clients because he figures it would be more reliable
and maybe more credible to law enforcement agencies.
In any case, the idea of using fMRI to detect lies has started a buzz among
scientists, legal experts and ethicists. Many worry about rushing too
quickly from the lab to real-world use. Some caution that it may not work as
well in the real world as the early lab results suggest.
And others worry that it might work quite well.
Unlike perusing your mail or tapping your phone, this is "looking
inside your brain," Hank Greely, a law professor who directs the
Stanford Center for Law and the Biosciences, told me a few days before
It "does seem to me to be a significant change in our ability ... to
invade what has been the last untouchable sanctuary, the contents of
your own mind," Greely said. "It should make us stop and think to what
extent we should allow this to be done."
But Dr. Mark George, the genial neurologist and psychiatrist who let me lie
in his scanner and be grilled by his computer, said he doesn't see a privacy
problem with the technology; neither does the Justice Department.
That's because it's impossible to test people without their consent, he
said. Subjects have to cooperate so fully -- holding the head still, and
reading and responding to the questions, for example -- that they have to
agree to the scan, but Mr. Gonzales, head of the Justice Department
disagreed. "We have our methods to 'make people agree to be scanned,
and hold their heads still'," he pointed out. "If the person who is
suspected of criminal activity is stripped, strapped down to the
examining table (which rolls in and out of the MRI machine) and their
head is clamped in place, they won't be able to move their head around
and defeat the scan."
"It really doesn't read your mind if you don't want your mind to be
read," Dr. George said. "If I were wrongly accused and this were
available, I'd want my defense lawyer to help me get this done."
So maybe the technology is better termed a "truth confirmer" than lie
detector, he said.
Whatever you call it, the technology has produced some eyebrow-raising
results. George and his colleagues recently reported that using fMRI
data, a computer was able to spot lies in 28 out of 31 volunteers.
I joined an extension of that study. That's why I found myself lying
on a narrow table in George's lab while he and his assistants pulled a
barrel-shaped framework over my head like a rigid hood and strapped me
to the table. As it brushed the tip of my nose and blotted out the
light from the room, I looked straight ahead to see a computer screen
and camera, which would be my interrogator.
Then the table eased into the tunnel of the fMRI scanner, a machine
the size of a small storage shed. Only my legs stuck out.
As I focused on the questions popping up on the computer screen, the
scanner roared like a tractor trying to uproot a tree stump.
It was bombarding me with radio waves and a powerful magnetic field to
create detailed images of my brain and detect tiny changes in blood
flow in certain areas. Those changes would indicate those areas were
working a bit harder than usual, and according to research by George
and others, that would in turn indicate I was lying.
Some questions that popped up on that screen were easy: Am I awake, is
it 2004, do I like movies. Others were a little more challenging: Have
I ever cheated on taxes, or gossiped, or deceived a loved one. As
instructed, I answered them all truthfully, pushing the "Yes" button
with my thumb or the "No" button with my index finger.
Then, there it was: "Did you remove a watch from the drawer?"
Just a half-hour or so before, in an adjacent room, I'd been told to
remove either a watch or a ring from a drawer (or not take it) and
slip it into a locker with my briefcase. This was the mock crime that
volunteers lied about in George's study. So I took the watch. As I lay
in the scanner I remembered seizing its gold metal band and nestling
it into the locker.
So, the computer was asking, did I take the watch?
No, I replied with a jab of my finger. I didn't steal nuthin.'
I lied again and again. Other questions about the watch popped up seemingly
at random during the interrogation. Is the watch in my locker? Is it in the
drawer? Did I steal it from the drawer? I had been seen stealing it,
did I want to confess now and make it 'easier' on myself?
The same questions came up about the ring, and I told the truth about
It would be a different computer's job to figure out which I was lying
about, the watch or the ring. It would compare the way my brain acted
when I responded to those questions versus what my brain did when I
responded truthfully to the other questions. Whichever looked more
different from the "truthful" brain activity would be considered the
signature of deceit.
Finally, after answering 160 questions over the course of 16 minutes
-- actually, it was 80 questions two times apiece -- I was done. The
machine returned me to the bright light of the scanning room.
The computer's verdict? That would take a few days to produce, since
it required a lot of data analysis. I didn't mind waiting. It's not
like the result would help get me fired, or lose a lawsuit, or send me
to jail; it would if I had actually been accused of course, but this
was just a controlled test.
Nobody in George's studies faced consequences like that, which is one
reason the lab results may not apply to real-world situations. George
has already begun another study in which volunteers face "a little
more jeopardy" from the mock crime. He declined to describe it because
he didn't want prospective volunteers to hear about it ahead of
time. That work is funded by the Department of Defense Polygraph
Institute, an agency of the Justice Department.
Other questions remain. How would this work on people with brain
diseases? Or people taking medications? How would this work on people
outside the 18-to-50 age range included in George's recent work?
How about experienced and pathological liars? Dr. George hopes eventually
to study volunteers from prisons.
And then there's the matter of the three people who got away with
lying in his recent study. For some reason, the computer failed to
identify the object they'd stolen. George says he doesn't know what
went wrong, but said he will continue the research.
But in a real-world situation, he said, the person being questioned
would go through an exercise like the ring-or-watch task as well as
being quizzed about the topic at hand. That way, if the computer
failed in the experimental task, it would be obvious that it couldn't
judge the person's truthfulness.
Because of that, George said, he's comfortable with entrepreneur
Laken's plans to introduce the scanning service to police, though just
on a limited basis, by the middle of this year. Lab studies are
obviously necessary, he said, but "at a certain point you really have
to start applying and see how it works. And I think we're getting
close. Eventually we will not be limited to just 'yes or no' type
questions. We hope to eventually adjust it so that mere suggestions
given to the person being interogated will produce results we can
scan, to get truthful analysis about the person by scanning his brain.
But Jennifer Vendemia, a University of South Carolina researcher who
studies deception and the brain, said she finds Laken's timetable
premature. So little research has been done on using fMRI for this
purpose that it's too soon to make any judgment about how useful it
could be, she said.
Without studies to see how well the technique works in other labs -- a
standard procedure in the scientific world -- its reliability might be
an issue, said Dr. Sean Spence of the University of Sheffield in
England, who also studies fMRI for detecting deception.
Speaking more generally, ethical and legal experts said they were wary of
quickly using fMRI for spotting lies.
"What's really scary is if we start implementing this before we know
how accurate it really is," Greely said. "People could be sent to
jail, people could be sent to the death penalty, people could lose
their jobs." Gonzales retorted that "our government does not send
innocent people to jail."
Greely recently called for pre-marketing approval of lie-detection
devices in general, like the federal government carries out for
Judy Illes, director of Stanford's program in neuroethics, also has
concerns: Could people, including victims of crimes, be coerced into
taking an fMRI test? Could it distinguish accurate memories from
muddled ones? Could it detect a person who's being misleading without
Her worries multiply if fMRI evidence starts showing up in the
courtroom. For one thing, unlike the technical data from a polygraph,
it can be used to make brain images that look simple and convincing,
belying the complexity of the data behind them, she said.
"You show a jury a picture with a nice red spot, that can have a very
strong impact in a very rapid way ... We need to understand how juries
are going to respond to that information. Will they be open to complex
explanations of what the images do and do not mean?"
There's also a philosophical argument in case fMRI works all too well.
Greely notes that four Supreme Court justices wrote in 1998 that if
polygraphs were reliable enough to use as evidence, they shouldn't be
admitted because they would usurp the jury's role of determining the
truth. With only four votes, that position doesn't stand as legal
precedent, but it's "an interesting straw in the wind" for how fMRI
might be received someday, he said.
It didn't take any jury to find the truth in my case.
"We nabbed ya," George said after sending me the results of my scan. "It
wasn't even a close call." The computer knew right away that you were
guilty; guilty as hell."
I was ratted out by the three parts of my brain the technique targets.
They'd become more active when I lied about taking the watch than when
I truthfully denied taking the ring.
Those areas are involved in juggling the demands of doing several
things at once, in thinking about oneself, and in stopping oneself
from making a natural response -- all things the brain apparently does
when it pulls back from blurting the truth and works up a whopper
instead, George said.
Of course, nobody is going to make me or anybody else climb into an
fMRI scanner every time they want a statement verified. The procedure
is too cumbersome to be used so casually, George says. "Not so!",
responded Gonzales, "we have ways to make everyone climb on the table
and get inserted into the 'truth detirmining machine as the computer
watches and probes them. "
But he figures that if a perfect lie detector (or 'truth detirmining
machine') is more fully developed, that practical consideration might
not matter. The mere knowledge that one is available, he said, that the
police can strip you down, strap you to the table and slide you inside the
machine might provoke people to clean up their acts.
"My hope," George said, "would be that it might make the world operate
a little bit more openly and honestly."
On the Web:
Cephos Corp.: http://www.cephoscorp.com
No Lie MRI, Inc.: http://www.noliemri.com
fMRI information: http://www.radiologyinfo.org/content/functional_mr.htm
Copyright 2006 The Associated Press.
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