Very few professionals have extensive experience with BOTH popular
types of lie-detection.
I do. Since I also offer the traditional
'wired' examinations (see GroganPolygraph.com), I know the advantages
--and disadvantages-- of both 'wired' polygraph and 'voice'
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the psychological advantage of them being secured to a chair with 4 wired
connections made to their body (chest, stomach, left upper arm, and
fingers on right hand).
But these are unnatural attachments,
and there are strict requirements that do not allow that the slightest
movement can be made or the test is corrupted, which can themselves
sometimes add enough stress to affect the results.
And, because with
'wired' polygraph the client can only have 3 or 4 relevant
questions (questions about the client's issue or situation) asked, the
exam often leaves more questions unanswered than answered.
Internet is full of 'How To Beat A (wired) Polygraph' advertisments;
known as 'countermeasures', if not caught they can easily allow a test to
be falsely passed.
like: --more questions can be asked
--it is so powerful if used
secretly in contract negotiations and other private discussions to get
unfair advantage that criminal laws now require written permission to use
--NOTHING is attached to or touching the
--developed for United States Military Intelligence looking
for an alternative to wired polygraph
--insurance companies quietly
use it to screen for suspected false loss claims
--used by California
Highway Patrol, the Los Angeles County Sheriff Department, nearly 200
California police agencies, and nearly 2000 law-enforcement
agencies instead of 'wired' polygraph examinations
--The voice ‘micro-tremor’ is governed by the central nervous system
and reacts to the psychological stimuli (the question) in the same
time frame as does polygraph,
BUT the difference being that with voice,
the ‘micro-tremor’ recovers almost instantly, while with polygraph
the required recovery time is 25 seconds or more inbetween questions. The process is
therefore far more user-friendly as there is no artificial waiting
time between question sets.
--For some special situations where privacy can
assist with embarassment or security issues, testing
can be done with equal accuracy over the phone.
'countermeasures' (no way to 'trick' or 'beat' this
Voice lie detection, following a paralinguistic
pre-test interview, is very accurate. The figures most often cited
are in the 95% - 98% range.
Used successfully by US military
troops on terrorists in war zones in combat situations in Iraq and in
Accordingly, this technology is rapidly replacing the
polygraph at many law enforcement agencies. There are several independent and
unbiased studies conducted regarding the accuracy of voice stress
analysis. Each of them show the high accuracy of the voice lie
Following the 9/11 attack on America, Congress provided
President Bush with The Airport Security Federalization Act of 2001, which
he signed into law. This includes the provision that airports
will “provide for the use of Voice Stress Analysis or other technologies
to prevent a person who might pose a danger to air safety from
boarding the aircraft…”. Congress and this provision further legitimized
the use of voice stress analysis as a means of truth verification.
other type of lie-detection has received such a strong endorsement.
Comparing the two types of lie-detection: Some have compared wired
polygraph as being like old-fashioned wired telephone lines and Voice Lie
Detection as being like modern digital telephone service.
have enacted legislation regulating the use of voice lie detection on
persons without their express consent in advance, yet even further endorsing
the validity of voice lie detection.
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More importantly: I have conducted BOTH exam types at the SAME
time on the SAME person many times; the final outcome (Pass or
Fail) matched on each every time.
The wired polygraph industry
does not like voice-based lie-detection; the voice polygraph industry
does not like wired-based lie-detection. Some call it the 'Toyota and
Nissan' comparison: both do their job, similar yet different.
side will try to 'sell' theirs as being the best and the other as
less. Each will cite 'studies' and 'statistics': some are accurate, some
I know both and perform both; I am certified for
Only someone experienced with both and who offers both can give
an accurate & unbiased opinion.