Brain Scans as Evidence: Truths, Proofs, Lies, and Lessons - Francis X. Shen and Owen D. Jones

• Jurisdiction: United States,Federal
• Publication year: 2011
• Citation: Vol. 62 No. 3

Brain Scans as Evidence: Truths, Proofs, Lies, and Lessons

by Francis X. Shen* and Owen D. Jones**

I. Introduction

This Brain Sciences in the Courtroom Symposium is both timely and important. Given recently developed and rapidly improving brain imaging techniques that enable non-invasive detection of brain activity, civil and criminal courts increasingly encounter attorneys proffering brain scans as evidence.¹ The reason is simple. In addition to caring about how people act-such as when they cause a person's death or sign a will-the legal system's inquiries frequently turn on determining what people were thinking, or were capable of thinking, when they acted.

* Visiting Scholar, Vanderbilt University Law School. Associate Director, MacArthur Foundation Law and Neuroscience Project. University of Chicago (B.A., 2000); Harvard Law School (J.D., cum laude, 2006); Harvard University (Ph. D., 2008).

** New York Alumni Chancellor's Chair in Law & Professor of Biological Sciences, Vanderbilt University. Director, MacArthur Foundation Law and Neuroscience Project. Amherst College (B.A., magna cum laude, 1985); Yale Law School (J.D., 1991).

This Article was prepared with the support of the John D. and Catherine T. MacArthur Foundation under Award No. 07-89249-000-HCD.

1. For general introductions to law and neuroscience, see Henry Greely & Anthony Wagner, Reference Guide on Neuroscience, in Federal Judicial Center Reference Manual on Scientific Evidence (3d ed., forthcoming 2012); Owen D. Jones, Jeffrey D.

Schall & Francis X. Shen, Law and the Brain (forthcoming 2013), available at www.http://www.vanderbilt.edu/lawbrain; MacArthur Primer on Law & Neuroscience (Stephen J. Morse & Adina L. Roskies, eds., forthcoming 2012); Oliver R. Goodenough & Micaela Tucker, Law and Cognitive Neuroscience, 6 Ann. Rev. L. Soc. Sci. 61 (2010); Owen D. Jones et al., Brain Imaging for Legal Thinkers: A Guide for the Perplexed, 2009 Stan. Tech. L. Rev. 5; Francis X. Shen, The Law and Neuroscience Bibliography: NavigatingThe Emerging Field of Neurolaw, 38 Int'l. J. Leg. Inform. 352 (2010); Stacey A. Tovino, Functional Neuroimaging and the Law: Trends and Directions for Future Scholarship, 7 Am. J. Bioethics 44 (2007). For additional resources, see the home page of the MacArthur Foundation Law and Neuroscience Project at www.lawneuro.org.

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In criminal law, for example, the same act can yield anything from mere probation to decades in prison, depending on what the legal fact finders believe a defendant was probably thinking. In the civil context, the beliefs held by a defendant about a particular risk are often central to a plaintiff's recovery. The unavoidable consequence is this: what a brain was actually doing at the time of an act, and indeed what a brain in court recollects about past acts, often matters a great deal to the administration of justice. And in all such such cases, judges and jurors have it hard. It is simply not easy to read the mind of a stranger or to assess with complete confidence either the subjective belief or objective accuracy of expressed recollections.

In all of human and legal history prior to just a few years ago, we have had to infer what was going on in a person's brain from a triangulation of circumstances, testimony, and projections of introspections. Against this historical backdrop, modern neuroscientific techniques seem to offer the tantalizing promise of informative, relevant, and high-tech cranial tours. Although it will rarely, if ever, be the case that an act of legal relevance is performed as a person is being brain-scanned, attorneys increasingly think-or hope-that brain scans preceding or following an act ofinterest can tell us something legally relevant about a person's capacities, predispositions, intentions, or frames of mind.

This Article proceeds in three parts. Part I explores a particular context of law and neuroscience: the use of brain scans as evidence of lying or truth-telling. Part II illustrates the use of those scans by discussing the landmark 2010 federal criminal trial United States v. Semrau.² That case involved the first federal hearing-which one of us (Jones) attended-regarding the admissibility of testimony about brain scans proffered as evidence of whether a person was lying or telling the truth. Part III identifies five issues relevant to future encounters between courts and brain scanning evidence. Sufficient scientific progress in addressing issues of experimental design, ecological and external validity, ensuring subject compliance with researcher instructions, false memories, and making individual inferences from group data may one day make brain scan evidence admissible in new legal contexts. But, in the illustrative case of lie detection, not yet.³

2. No. 07-10074 JPM (W.D. Tenn. June 17, 2010) (PACER). After a thirteen-day jury trial, on June 17, 2010, the jury found Semrau guilty on three counts of health care fraud in violation of 18 U.S.C. § 1347 (2006), and not guilty on eleven counts of money laundering and fifty-seven counts of health care fraud. United States v. Semrau, No. 2:10-cr-10074-JPM, 2011 WL 9258, at *1 (W.D. Tenn. Jan. 3, 2011).

3. Judge Pham's Report and Recommendation in Semrau ultimately resulted in the exclusion of the evidence on the grounds of Federal Rule of Evidence 702 (testimony by

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Still, Semrau is a poignant reminder that lawyers need not, and indeed often will not, wait for neuroscience research consensus before attempting to introduce brain imaging evidence that may bolster their clients' cases. The stakes are so high, and the emerging neuroscience technologies so novel and alluring, that we are likely to see similar cases more frequently in courtrooms in the years to come. And this means judges must be ready to evaluate, and lawyers ready to litigate, whether testimony regarding brain scans should be admitted as evidence for new and controversial purposes.

II. BRAIN SCANS, LIES, AND LAW

In this section, we provide brief overviews of the main brain-based lie detection techniques and the scientific and legal contexts for evaluating

them.

A. Brain-Based Lie Detection: Techniques

For centuries, humans have tried to improve their ability to detect deception by harnessing the latest technological advances.⁴ Brain scanners as lie detectors are thus understandably alluring and have generated much discussion in scientific and legal circles.⁵ Although it

experts) and Rule 403 (probative value and unfair prejudice). See Report and Recommendation, United States v. Semrau, No. 07-10074 M1/P (W.D. Tenn. May 31, 2010). After the Report and Recommendation was submitted on May 31, 2010, the defense filed an objection on June 9, 2010. Defendant's Response to the Government's Motion to Exclude the Usage of GAO Reports, United States v. Semrau, No. 07-10074 M1/P (W.D. Tenn. June 9, 2010). On June 10, 2010, the United States District Court for the Western District of Tennessee adopted the Report and Recommendation and granted the Government's motion in limine to exclude testimony regarding lie detection tests performed on the defendant. Order Denying Defendant's Motion To Dismiss, Denying Defendant's Motion for Judgment of Acquittal/to Dismiss and/or Motion for New Trial, and Denying Defendant's Motion to

Strike at 67, United States v. Semrau, No. 2:10-cr-10074-JPM (W.D. Tenn. Nov. 23, 2010)

[hereinafter Order]. Although the evidentiary ruling has no binding precedential value, that did not dampen national attention to the case. National media coverage included

Greg Miller, fMRI Lie Detection Fails a Legal Test, 328 Sci. 1336 (2010); Alexis Madrigal,

Eyewitness Account of "Watershed' Brain Scan Legal Hearing, Wired Science (May 17, 2010, 7:30 pm), http://www.wired.com/wiredscience/2010/05/fmri-daubert; Greg Miller, Can Brain Scans Detect Lying? Exclusive New Details From Court Hearing, Science Magazine (May 14, 2010, 12:09 pm), http://news.sciencemag.org/scienceinsider/2010/05/can-brain-scans-detect-lying-exc.html; Margaret Talbot, Brain Scans on Trial, The New Yorker (May 25,2010), http://www.newyorker.com/online/blogs/newsdesk/2010/05/brain-scans.htm.

4. See, e.g., Ken Alder, The Lie Detectors: The History of an American Obsession (2007); Committee to Review the Scientific Evidence on the Polygraph, National Research Council, The Polygraph and Lie Detection (2003).

5. See, e.g., Giorgio Ganis & Julian Paul Keenan, The Cognitive Neuroscience of Deception, 4 Soc. Neurosci. 465 (2009). Volume four of Psychology Press's Social

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is beyond the scope of this Article to fully introduce the neuroscience of lie detection, we offer a few basic observations.

There are two prominent techniques for brain based lie detection.⁶ The first, electroencephalography (EEG), measures electrical activity in the brain.⁷ In EEG studies, researchers place electrodes on a subject's skull to detect, localize, and record electrical activity within the brain as a subject performs tasks.⁸ The promise, as yet mostly unrealized, is that such technology could be used to determine-on the basis of

Neuroscience included eight articles, each highlighting a distinct approach to studying the neural correlates of deception. We recommend this volume for lawyers who want a window into the advancing science in this area of deception and neural correlation. Recommended general reviews of neuroscience-based lie detection evidence include Emelio Bizzi et al., Using Imaging to Identify Deceit: Scientific and Ethical Questions (2009); Anthony Wagner, Can Neuroscience Identify Lies?, in A Judge's Guide To Neuroscience: A Concise Introduction 13 (2010); Archie Alexander, Functional Magnetic Resonance Imaging Lie Detection: Is a "Brain Storm" Heading Toward the "Gatekeeper"? 7 Hous. J. Health L. & Pol'y 1 (2007); Paul S. Appelbaum, The New Lie Detectors: Neuroscience, Deception, and the Courts, 58 Psychiatry Serv....