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ttp://online.wsj.com/article/SB120612863077155601.html
PAGE ONE
The Polygraph Paradox
Lie detectors aren't perfect. But, convicted sex offenders concede, they may
be good enough
By LAURIE P. COHEN
March 22, 2008; Page A1
The lie detector won't die.
Polygraphy, the attempt to ferret out deception by monitoring changes in
subjects' breathing, sweating or pulse, has long been derided as "voodoo
science." Confessions made under polygraph aren't admitted as evidence in a
vast majority of U.S. courts without the consent of the accused. The
National Academy of Sciences says the technology isn't accurate enough to be
used for employee security screening.
Yet polygraph use is at the highest level in two decades. Government
agencies from local police departments to the CIA are increasingly using the
technology for job interviews. In U.S. courts lately, judges have expanded
the instances in which polygraph testing is mandated or admitted as
evidence.
In law enforcement, this lie-detector paradox is clearly on display.
Polygraphy is a centerpiece in an expanding range of parole and probation
programs that are designed to dissuade sex offenders and other felons from
committing more crimes.
The recent experience of convicted gay pedophile Paul Duncan shows the
polygraph's contradictions and, its proponents argue, its promise. Last
November, as part of a program in this southern Oregon town to monitor
paroled sex offenders, Mr. Duncan sat in a small windowless room in a
corrections center with polygraph sensors on his palm, chest, stomach and
arm. Under the program, a parolee who fails the test, or admits to parole
violations under the threat of a test, can be sent back to prison.
The machine's operator asked: "Have you had sexual contact with a minor
during the last six months?"
Mr. Duncan said he hadn't. The polygrapher judged him to be lying. Mr.
Duncan was sent to jail for 15 days.
In an interview after his release, the 33-year-old Mr. Duncan said reality
had been more complicated. Mr. Duncan said he hadn't, in fact, had contact
with a minor. But he admitted he had violated his parole in another way --
viewing online pornographic photos of young males, an activity he says had
sparked his past pedophilic episodes. Mr. Duncan says he believes that while
the polygraph got the specifics wrong, it revealed a broader truth: His
conscience was guilty.
"I didn't disclose my deviant fantasies -- and I deserved to fail," Mr.
Duncan said of the test. "Don't believe anyone who tells you polygraph
doesn't work."
Mr. Duncan's unusual endorsement is consistent with those provided by other
paroled felons. In interviews with The Wall Street Journal, a dozen
convicted sex offenders in Klamath Falls and Denver, Colo., said
lie-detector sessions exposed their parole violations. More importantly,
they say, the threat of upcoming tests serves as a deterrent to future
crimes. Polygraph proponents argue that this is a benefit the ongoing
polygraphy debate misses: The question shouldn't be whether the technology
is always accurate, they say, but whether it is useful.
Polygraphs have long been used as a tool to keep sex offenders from
relapsing, typically as part of maintenance programs that combine polygraphy
with group therapy and parole-officer supervision. Today, a majority of
jurisdictions use such programs for convicted sex offenders. Now,
post-conviction polygraphy appears poised to spread: Probation officers have
recently started deploying lie detectors in programs tailored to
domestic-abuse and drunk-driving offenders, as well.
Last July, Klamath Falls expanded its sex-offender program to cover
domestic-violence offenders. Two East Texas counties, Van Zandt and Wood,
recently began monitoring drug and alcohol offenders with lie detectors, and
polygraphy has also been used in monitoring drug and alcohol offenders in
Dallas and Houston.
Eric Holden, a psychologist and Dallas polygraph examiner, says that as
courts become familiar with how lie detectors are used with sex offenders,
the tests will be increasingly applied to other offenders. Polygraph testing
"will become a standard for supervising probationers of all kinds," says Mr.
Holden, who was one of the first to use polygraphy with sex offenders in the
early 1980s.
That tracks the lie detector's expanding use overall. The number of federal
polygraph programs has grown 53% in the past decade, according to the
Defense Academy of Credibility Assessment, which trains polygraph examiners
for the government. There are roughly 5,000 polygraph examiners in the U.S.,
conducting some 1.6 million tests a year -- both up about 50% from a decade
ago, estimates the industry's largest trade group, the American Polygraph
Association. This year, APA membership reached its highest level since 1988,
when Congress outlawed pre-employment lie-detector testing by most
nongovernmental employers.
Unlicensed Operators
Critics remain vocal. The idea behind polygraphy is that physiological
changes often accompany lying. But subjects can fool the machine, detractors
say. While subjects are supposed to sit still to ensure an accurate reading,
some may try to distort results by squeezing muscles in the buttocks, for
example, or lightly biting the tongue. Precise polygraphy also depends on
the ability of the machine's operator to formulate questions and analyze
results; nearly half of U.S. states, including California, don't require
examiners to be licensed.
Even with trained polygraphers, the technology fails to detect those telling
lies, or wrongly implicates those telling the truth, about 10% of the time,
according to field studies reviewed by the National Academy of Sciences.
Such reliability levels are too low for many uses. In making employment
decisions about thousands of people, for example, lie detectors could
wrongly implicate hundreds of them, the academy wrote in a 2003 study.
Polygraphy performs "well above chance, though well below perfection," the
study concluded.
High-profile cases have spotlighted these imperfections. Polygraph testing
failed to raise suspicions about Aldrich Ames, the former CIA agent who
spied for the Soviets. The Federal Bureau of Investigations' interpretation
of Los Alamos scientist Wen Ho Lee's exam results wrongly implicated him of
being an agent for China.
Proponents say accuracy rates have improved. Increasingly, hand-scoring by
examiners has been replaced by computerized algorithms that proponents say
filter out human errors and biases. Examiners have also tried to counter
polygraph-foiling techniques, employing, for example, what they call "butt
pads" to detect muscle squeezing.
When it comes to dissuading released offenders from relapsing, polygraphy is
superior to other methods, adherents say. It beats self-reporting -- simply
asking parolees whether they've violated their parole terms -- a method
previously employed by many jurisdictions that have switched over to
post-conviction polygraphy.
Eighty Offenders
In Klamath Falls, a town of 20,000 people and the seat of Oregon's
mountainous Klamath County, some 80 convicted sex offenders are required to
attend weekly therapy sessions and probation-officer meetings. They're also
required to submit to lie-detector t
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