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Brain Fingerprinting Testing in the case of Harrington v. State

Thomas H. Makeig, counsel to Dr. Lawrence A. Farwell1

 In Harrington v. State, Case No. PCCV 073247(Iowa District Court for Pattawattamie County), decided March 5, 2001, petitioner Terry Harrington sought to overturn a 1978 murder conviction on several grounds, including an allegation that newly discovered evidence in the form of Farwell Brain Fingerprinting® entitled him to a new trial. 

Standard of review.  To obtain relief, the petitioner had to show that the newly discovered evidence was unavailable at the original trial, and that the new evidence, if introduced at the trial, would probably change the verdict.  Additionally, in view of the fact that the proffered evidence consisted of a novel forensic application of psycho-physiological research methods, the court was required to determine whether this scientific evidence was sufficiently reliable to merit admission into evidence and, if admitted, whether the weight of the scientific evidence was sufficiently compelling to change the verdict.

The U.S. Supreme Court has held that the standard for admissibility of novel scientific evidence is a showing of reliability based on (1) whether a theory or technique can be (and has been) tested; (2) whether it has been subjected to peer review and publication; (3) whether, in respect to a particular technique, there is a high known or potential rate of error, and whether there are standards controlling the technique’s operation; and (4) whether the theory or technique enjoys general acceptance within a relevant scientific community.  Daubert v. Merrell Dow Pharmaceuticals, Inc. 509 U.S. 579, 594 (1993) (construing Federal Rule of Evidence 702).  The Iowa Supreme Court has not formally endorsed this federal evidentiary standard, but it has consistently used the Daubert factors in assessing the admissibility of novel scientific evidence.  See, e.g., Williams v. Hedican, 561 N.W.2d 817 (Iowa 1997).

Description of Brain Fingerprinting.  Farwell Brain Fingerprinting is a real-time psycho-physiological assessment of a subject’s response to stimuli in the form of words or pictures presented on a computer monitor.  As a forensic method, the test assesses the subject’s knowledge of a crime scene or of the instrumentalities or fruits of a crime, and it can also be used to assess knowledge of the particulars of an alibi scene or sequence of events. 

Brain Fingerprinting uses electroencephalography to measure evoked potentials, known as the P300 (electrical events beginning 300 milliseconds after exposure to a stimulus), that are characteristic of the information processing that accompanies recognition of stimuli in comparison to a remembered context.  Dr. Farwell has extended the analysis of this evoked potential further in time to take account of additional information that has not been analyzed hitherto, and he refers to this extension of the P300 as a “MERMER” (“memory and encoding related multifaceted electroencephalographic response”).  Just as a personal computer emits a characteristic sound whenever its central processing unit is transferring information from or to the hard drive, the human brain emits a characteristic P300 (and MERMER) electrical response whenever the subject responds to a stimulus by updating his memory context to take account of the stimulus.  The P300/MERMER response is not evoked when the stimulus is irrelevant to the subject’s memory context. 

Accordingly, if the person is a witness to or perpetrator of the crime, his response to stimuli that betray accurate details of the crime (“probes”) will evoke a P300/MERMER response.  Other items known to the person regardless of whether he was present at the crime (“targets”) also evoke the response and permit the tester to establish a baseline from which to compare the person’s responses to the probes.  Other stimuli that have no relevance either to the crime or to anything in the subject’s memory (“irrelevants”), establish a baseline for a flat response (no P300/MERMER evoked).  The signals obtained from the subject’s response to multiple presentations of approximately one dozen each of probes and targets, and twice as many irrelevants, are averaged using analytical tools that are standard in the field of electroencephalographic psycho-physiology, so that an overall result is obtained, demonstrating whether the probes have evoked a P300/MERMER recognition response or a flat non-recognition response. 

A similar test can be administered to probe the subject’s alibi defense; however, in the case of an alibi, all that can usually be determined is whether the alibi story has validity as the subject’s remembered experience: it is not usually possible to determine whether the exact timing of the alibi experience places the subject away from the crime scene at the time of the crime. 

Brain Fingerprinting, using standard P300 analysis, typically yields an “information present” or “information absent” result with a statistical confidence in excess of 95% (and usually higher than 99%), and Dr. Farwell is able to increase the confidence factor when utilizing the additional signal information contained in the MERMER.  In research trials, Brain Fingerprinting has a track record of more than 150 correct determinations of “information present” or “information absent,” and no incorrect results, although this degree of accuracy is achieved partly by calibrating the test’s analytical methods to return an indeterminate result, with no commitment to “information present” or “information absent,” in about 3% of cases.

The availability of fresh and detailed probes is essential to the efficacy of the test.  Indeed, it has been anticipated that, once the reliability of the science underlying Brain Fingerprinting is established, the principal line of attack for parties opposing the use of a Brain Fingerprinting test result in a trial will be to challenge the evidentiary value of the specific probes that have been employed.  Dr. Farwell acknowledges that Brain Fingerprinting cannot be successfully applied in cases where the subject has been exposed to all the known details of the crime scene, fruits and instrumentalities, so that he will probably return an “information present” or an indeterminate result to any probes that are offered. 

The Brain Fingerprinting assessment of Harrington.  In the Harrington case, Dr. Farwell developed a series of probes for the crime scene, and a separate series of probes for the petitioner’s alibi, from previously undisclosed police files.  Dr. Farwell administered the test to Harrington in May 2000 and, in October 2000, he rendered a report to the Iowa District Court analyzing the MERMER responses.  Dr. Farwell supplemented the report with a separate analysis based solely on P300 signals on November 10, 2000.  Both analyses produced a result of “information absent” regarding the crime scene probes and “information present” regarding the alibi probes, with a high degree of statistical confidence (over 99%).

Proceedings in the Iowa District Court.  The District Court held a one-day hearing on the Brain Fingerprinting evidence on November 14, 2000.  The court took preliminary testimony on Dr. Farwell’s credentials, the efficacy of the test and the reliability of the underlying science.  The court also examined the test results, subject to a later determination whether this scientific evidence was sufficiently reliable to be admissible. 

At the November 14 session, Dr. Farwell testified and was cross-examined on the basis of his test reports.  Additionally, two other psycho-physiologists with expertise in electroencephalo­graphy, Prof. William Iacono of the University of Minnesota and Prof. Emanuel Donchin of the University of Illinois at Champaign/Urbana, testified on Dr. Farwell’s credentials, his test reports and the science underlying the Brain Fingerprinting test.  Prof. Iacono testified at Harrington’s request, and Prof. Donchin was called by the state. 

Both experts validated the science underlying Brain Fingerprinting and acknowledged Dr. Farwell’s credentials; however, while Prof. Iacono validated the forensic application of P300 science based on his own research, Dr. Donchin asserted that the tester’s selection and presentation of the specific probes is the point at which science ends and art begins. 

The District Court’s ruling.  After briefs were submitted and other, unrelated grounds for post-conviction relief were tried, District Judge Timothy O’Grady issued his ruling on March 5, 2001.  The court determined that Brain Fingerprinting was new evidence not available at the original trial, and that it was sufficiently reliable to merit admission of the evidence;2 however, the court did not regard its weight as sufficiently compelling in light of the record as a whole as meeting its exacting standard, and thus it denied a new trial on this and the other grounds asserted by Harrington.

The court stated the following:

 

“In the spring of 2000, Harrington was given a test by Dr. Lawrence Farwell.  The test is based on a ‘P300 effect’.”

 

“The P-300 effect has been recognized for nearly twenty years.”

 

“The P-300 effect has been subject to testing and peer review in the scientific community.”

 

“The consensus in the community of psycho-physiologists is that the P­300 effect is valid.”

 

“The evidence resulting from Harrington's ‘Brain Fingerprinting test was discovered after the verdict.  It is newly discovered.”

 

Appeal.  Harrington has filed a notice of appeal to the Iowa Supreme Court.  The appellate court will determine whether to uphold the trial court’s gatekeeping determination that the Brain Fingerprinting evidence is sufficiently reliable to merit its reception into evidence.  The Iowa Supreme Court will also determine whether to defer to the District Court’s determination that, in light of the record as a whole, the Brain Fingerprinting evidence fails to discredit the verdict of the original trial, and it will review the other grounds asserted in support of Harrington’s petition for a new trial. 

Conclusion.  Dr. Farwell is pleased that the first trial court to perform the gatekeeping function in regard to Brain Fingerprinting has determined the test to be sufficiently reliable to merit admission into evidence.  This is an achievement that has consistently eluded every form of polygraphy for decades, and it is based on a common perception in the relevant scientific community that P300 science, and the statistical tools used to analyze its results, are well accepted.

Regarding Dr. Donchin’s contention that the selection of probes in Brain Fingerprinting is the end of science and the beginning of art, Dr. Farwell agrees that the selection of probes is a subjective element of the test; however, he asserts that this subjective element is the kind of evidence that judges and juries are competent to evaluate:  A non-scientist is well equipped with common sense and life experience to evaluate all the facts and circumstances of the case and determine whether a finding that the specific probes in question returned a scientific result of “information present” or “information absent” helps to establish the subject’s guilt.

Although the district court did not find that the probes developed for the Harrington test constituted a compelling impeachment of the verdict, we believe that Brain Fingerprinting test results will have a substantial impact on juries, both in cases where the test helps to exonerate the subject and in cases where it reveals his guilt.


[1]           Thomas H. Makeig, P.C., Law Office, 500 North Third Street, Suite 213, P.O. Box 931, Fairfield, Iowa 52556.  Telephone: (641) 472-2235; fax: (641) 472-6347; email: Tmakeig@iowabar.org.

[2]           The court admitted only Dr. Farwell’s P300 analysis, and not the MERMER-based analysis, on grounds that the MERMER analysis had not been subjected to sufficient peer review and publication.  A paper by Drs. Farwell and Smith on the MERMER has subsequently been published in a leading forensic science journal.

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