28-06-2014, 03:53 PM
“BRAIN FINGERPRINTING:” A CRITICAL ANALYSIS
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ABSTRACT
Recent efforts by various investigators have been directed at using brain waves in
detection of deception. One investigator, Lawrence A. Farwell, left academia about
a decade ago and founded his company, “Farwell Brain Fingerprinting,” BF. ( See
http:/www.brainwavescience) This business is actively commercializing a
putative deception-revealing technology in connection with forensic and related
areas. As stated on its web site, “Farwell Brain Fingerprinting is a revolutionary
new technology for solving crimes, with a record of 100% accuracy in research with
US government agencies and other applications…. The technology is fully developed
and available for application in the field.” The present review undertakes a careful
analysis of these claims and their background with reference to the one refereed,
publication in a major psychophysiology journal which Farwell co-authored
(Farwell & Donchin, 1991), the voluminous material on the web address cited above,
Farwell’s U.S. Patents, court records, and the work of various other researchers.
Prior to this analysis, the present review briefly discusses the P300 event-related
brain potential which is the key element of most of the published brain-wave based
deception research. The “Guilty Knowledge Test” or GKT, which in a form
modified for P300 methods, yielded the P300 protocol for detecting concealed,
crime-related information, is also reviewed, followed by a review of the P300-based
deception detection literature. The issue of P300-based tests’ reported accuracies is
also considered. Since Farwell claims that his method is based on a brain activity
index, the “MERMER,” which goes beyond P300, an attempt is also made to
analyze this variable, based, of necessity, solely on U.S. Patent material. The review
then closely examines Farwell’s recently promoted retrospective application of BF
in which the technology is purportedly utilized to exonerate previously convicted—
some long ago—felons. Finally, the review highlights methodological problems
associated with BF and related methods, including vulnerability to countermeasures
and difficulty with developing adequate and appropriate test material, leading to
the concluding impression that the claims on the BF web site are exaggerated and
sometimes misleading. It is documented that in fact U.S. government agencies most
concerned with detecting deception do not envision use of BF. Finally, prospective
users and buyers of this technology are issued the classic Caveat Empt
INTRODUCTION
In the past few years, Lawrence A. Farwell, Ph.D., has been commercializing
a putative crime-solving technology closely related to detecting deception that he
calls “Farwell Brain Fingerprinting” (http:/www.brainwavescience). There has
been considerable publicity about this method, most of it cited on the web page. If
one peruses this page, one can see that much of the media have uncritically accepted
it with considerable excitement. Time Magazine has selected Dr. Farwell for the
“Time100: The Next Wave, the Innovators who may be the Picassos or the Einsteins
of the 21st Century” (although there has also been negative criticism, e.g.,
http://www.forensicevidencesite/Behv_Evi..._Iowa.html).
As of August 21, 2004, another of Farwell’s web sites implies that the
technique has perfect accuracy by using the phrase “100% accurate” as the
subheading of large sections of text (e.g.,
http://www.brainwavescienceChemistry.php). Previous recent versions of his
home page claimed this accuracy level very directly: “Farwell Brain Fingerprinting
is a revolutionary new technology for investigating crimes and exonerating innocent
subjects, with a record of 100% accuracy in research on FBI agents, research with
US government agencies, and field applications.” ( From
http:/www.brainwavescience, 2003.) On his main web site, as of August, 21,
2004, this claim was somewhat qualified: “Farwell Brain Fingerprinting is a
revolutionary new technology for solving crimes, with a record of 100% accuracy in
research with US government agencies and other applications.” In the present
review, analysis will demonstrate that there are many statements on these web sites
which can be questioned, and examples will be provided below. It is appropriate to
EARLY P300-BASED DECEPTION DETECTORS: THE ACCURACY ISSUE
Fabiani, Karis, and Donchin, (1983) showed that if a list of words, consisting
of rare, previously learned (i.e., meaningful) and frequent novel words were
presented one at a time to a subject, the familiar, previously learned words but not
the others elicited a P300. As suggested above, Rosenfeld, Nasman, Whalen,
Cantwell, Mazzeri (1987) recognized that the Fabiani et a. (1983) study suggested
that P300 could be used to detect concealed guilty knowledge, i.e., P300 could be
used as a potential lie detector: Therefore, P300 could index recognition of familiar
items even if subjects denied recognizing them. From this fact, one could infer
deception. The P300 would not represent a lie per se, but only a recognition of a
familiar item of information, the verbal denial of which would then imply deception.
Farwell has also emphasized this distinction on his web site, although as an
academic nicety which in no way affects the claims of the BF approach. Farwell and
Smith (2001), however, seem to have over-extended this distinction: “Brain
MERMER testing…has almost nothing in common with ‘lie detection’ or
polygraphy. Polygraphy is a technique of interrogation and detection of
deception…Brain MERMER testing does not require any questions of or answers
from the suspect. The subject neither lies nor tells the truth during the procedure,
and in fact the results of MERMER testing are exactly the same whether the subject
lies or tells the truth at any time
RETROSPECTIVE APPLICATION OF BF: THE HARRINGTON CASE.
The BF web page cites the Harrington case (Harrington vs. Iowa, 2000) as
the one which was admitted to court, and which illustrates how BF can be used to
exonerate wrongly convicted, incarcerated persons. By way of background, one
should be aware that Harrington was sentenced to life over 20 years ago for the
murder of a security guard. Two decades later, his attorneys appealed for a reversal
on several grounds, mostly including suppression of evidence by authorities and
recantation by dubious witnesses, but also including BF evidence. (See Harrington
vs Iowa, 2000; see also
http://www.judicial.state.ia.us/supreme/...p#_ftnref6.
This is the final ruling by the Iowa Supreme Court. It contains references to the
earlier proceedings.) In his contribution to the recent appeal, Farwell constructed a
set of probes, targets, and irrelevants based on the facts of the crime, including
incidental details of the murder scene, the getaway route, and so forth. When tested
on these, Harrington apparently had no memory of the crime details, leading to the
naïve inference that being innocent, he wasn’t there and couldn’t store the scenario
details. This inference was naive because notwithstanding the fragility of incidental
memory retention, particularly during a highly emotionally charged act, as
discussed above, the stimulus set was developed and the test was administered more
than 20 years after the event!
COUNTERMEASURES, METHODOLOGICAL, AND ANALYTIC ISSUES
One of the most serious potential problems with all deception-related
paradigms based on P300 as a recognition index is the potential vulnerability of
these protocols to countermeasures (CMs. These are covert actions taken by
subjects so as prevent detection by a GKT; See Honts & Amato, 2002; Honts, ,
Devitt, , Winbush, & Kircher, 1996 ). One might think that CM use would be
detectable, and thus not so threatening to P300-based deception detection. For
example, if the subject simply failed to attend to the stimuli, then there would be no
P300s to the targets, and that would indicate non-cooperation. If, as an alternative
CONCLUSIONS
One may read on the BF web site the following claim:
“Farwell Brain Fingerprinting is a revolutionary new technology for solving crimes,
with a record of 100% accuracy in research with US government agencies and other
applications. The technology is proprietary and patented. Farwell Brain
Fingerprinting has had extensive media coverage around the world. The technology
fulfills an urgent need for governments, law enforcement agencies, corporations,
and individuals in a trillion-dollar worldwide market. The technology is fully
developed and available for application in the field.”
One might agree about the facts that the technology is proprietary and
patented (indeed there are several patents on P300-based detection of concealed
information also, the earliest of which antedate Farwell’s), and that BF has had
extensive media coverage, as noted above. There is considerable doubt, however,
about fulfilling urgent needs by U.S. Government agencies. This may be confirmed
by reading a report by the U.S. General Accounting Office to Senator Charles E.
Grassley entitled “Federal Agency Views on the Potential Application of “Brain
Fingerprinting.” (GAO-02-22). This report stated that “Officials representing CIA,
DOD, Secret Service, and FBI do not foresee using the Brain Fingerprinting