Plant Trees SF Events 2006 Archive: 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020


The New Scientist                                     January 5, 2006


The lie detector you'll never know is there

By Paul Marks

THE US Department of Defense has revealed plans to develop a lie
detector that can be used without the subject knowing they are being
assessed. The Remote Personnel Assessment (RPA) device will also be
used to pinpoint fighters hiding in a combat zone, or even to spot
signs of stress that might mark someone out as a terrorist or suicide

In a call for proposals on a DoD website, contractors are being given
until 13 January to suggest ways to develop the RPA, which will use
microwave or laser beams reflected off a subject's skin to assess
various physiological parameters without the need for wires or skin
contacts. The device will train a beam on "moving and non-cooperative
subjects", the DoD proposal says, and use the reflected signal to
calculate their pulse, respiration rate and changes in electrical
conductance, known as the "galvanic skin response". "Active
combatants will in general have heart, respiratory and galvanic skin
responses that are outside the norm," the website says.

Because these parameters are the same as those assessed by a
polygraph lie detector, the DoD claims the RPA will also indicate the
subject's psychological state: if they are agitated or stressed
because they are lying, for example. So it will be used as a "remote
or concealed lie detector during prisoner interrogation".

But finding ways to fulfil the DoD's brief will pose a practical
challenge, says Robert Prance, an electrical engineer at the
University of Sussex, UK, who specialises in non-invasive sensors.
"They might capture breathing rate with an infrared laser that senses
chest vibration, but how they will measure a pulse through clothes,
for instance, is a very big question."

If the RPA is ever produced, it is likely to prove controversial. A
remote lie detector would face even more difficulties than standard
polygraph tests, which were themselves the subject of a damning 2003
report from the US National Academy of Sciences. "There is no way a
polygraph test can be carried out usefully without the subject
knowing, because you actually want the person to worry about certain
questions," says Bruce Burgess, an examiner with polygraph firm
Distress Services of Leatherhead, Surrey, UK.

But Steve Wright, a conflict analyst at Leeds Metropolitan
University, UK, raises the prospect of people identified as suspects
by the device being captured and subjected to secret "prisoner
rendition" as a result. And he warns that the RPA could introduce a
"chill factor" into everyday life.

Related Articles

     * Gut reactions may rumble a liar
     * 31 October 2005
     * Liars' brains make fibbing come naturally
     * 30 September 2005
     * Deception special: The truth about lies
     * 30 July 2005


     * Remote Personnel Assessment request
     * Robert Prance, University of Sussex
     * Distress Services
     * <>
For updates and info, contact scott at planttrees dot org.