HOW EXPERTS HAVE DOMINATED THE NEUROSCIENCE NARRATIVE IN CRIMINAL CASES FOR TWELVE DECADES: A WARNING FOR THE FUTURE.

• Author: Denno, Deborah W.
• Position: Imagining the Future of Law and Neuroscience

TABLE OF CONTENTS

Introduction. 1219 I. Phineas Gage and the Push-and-Pull of Experts. 1224 A. Expert Physicians 1225 B. Competing Ideologies 1228 II. The Insanity Defense Across Twelve Decades 1232 A. Major Insanity Tests 1232 B. Crime Rate Trends 1236 C. The Twelve-Decade Neuroscience Study. 1239 1. Goals. 1239 2. Methodology. 1240 3. Drawbacks 1241 III. The Future of the Insanity Defense and Neuroscience 1242 A. Insanity Defense Rates. 1243 1. Reasons for the Plummeting Rates. 1248 2. Dominance of Expert Testimony. 1251 B. Successful Insanity-Related Claims 1256 C. Pure Successful Insanity Cases 1257 D. The Role of Non-Neuroimaging Tests. 1258 IV. How Insanity Defense Narratives Use Neuroscience Experts 1261 A. The Defense's Narrative. 1261 1. Police Officer at the Elbow: People v. Armstrong 1263 2. Crime in Broad Daylight with No Attempt to Flee: State v. Currie. 1265 3. Juvenile Committing Patricide: People v. Baker 1267 4. Attempted Murder of a Police Officer: Dixon v. State 1269 5. Going to Heaven: People v. Wilhoite 1271 B. The Prosecution's Narrative 1273 1. Evidence of Defendant's Malingering. 1274 2. Implications of Malingering 1277 Conclusion. 1279 Appendix A 1280 I. Research Methodology: Case Seakches, the Coding Process, and Coding Insanity 1280 A. Case Searches 1280 1. Search Terms 1281 2. Criteria for Relevancy. 1282 B. The Case Coding Process. 1283 1. General Case Coding 1283 2. Training Coders 1285 C. Coding Insanity Cases. 1285 1. General Coding. 1285 2. Successful Insanity Case Coding. 1287 INTRODUCTION

"We know the future only by the past we project into it." (1)

On September 13, 1848, Phineas Gage's brain made history. (2) Gage, a construction foreman, was working with his crew on a railway line in Cavendish, Vermont, when, in minutes, his life changed forever. (3) Without warning, an explosion erupted, propelling a threeand-a-half-foot iron rod straight through Gage's head. (4) The rod's trajectory was bizarre and inconceivable: it entered the left side of Gage's face behind his eye and then soared out of the top of his skull. (5) Landing thirty feet away, the rod was "smeared with brains and blood." (6) Yet, what followed this tragedy would be most improbable of all. The twenty-five-year-old Gage survived. (7) Immediately after his injury, Gage was conscious, alert, speaking to those around him, and walking, mostly unassisted. (8) He would live for another eleven years. (9)

The Gage case is considered "one of the great medical curiosities of all time," (10) a staple in primary textbooks in neuroscience and psychology, and a frequent citation in articles and reports. (11) The injury was also the first opportunity to focus on such seemingly complex qualities as judgment, temperament, and impulse control, thus heralding in the field of neuropsychology and the traditional case study approach to the cognitive and social neurosciences. (12) Yet, the fantastical accounts of Gage's post-accident personality changes, "too monstrous for belief," (13) are what captivated history and made Gage famous. (14) According to one familiar view, as a result of his injury, Gage was "an unstable, impatient, foul-mouthed, work-shy drunken wastrel, who drifted around circuses and fairgrounds, unable to look after himself, and dying penniless in an institution." (15) Indeed, my survey of the last thirty-seven law review articles that mentioned Gage consistently depicted him as "'antisocial,' 'fitful,' 'irreverent,' 'grossly profane,' 'garrulous,' 'sexually promiscuous,' 'reckless,' 'unreliable' and 'irresponsible.'" (16)

This heinous and distorted biography of Gage was fueled in part by the limited number of primary sources documenting Gage's life, coupled with his accident's unlikelihood. (17) Yet, just as important were the experts involved in assessing Gage's injuries (either directly or not) and reporting their opinions about them. For example, over a century after the accident, a prominent neuroscientist controversially wrote a book based in part on his negative assumptions about Gage's injuries and behavior to help analyze his patients. (18) We now know that many of the rumors about Gage--including the ones in that book--were false or undocumented. (19) Australian psychologist Malcolm Macmillan started to set the record straight in 2000 in his stunningly comprehensive book and articles. (20) According to Macmillan, Gage thrived in unexpected ways during his short lifetime, despite his injuries. (21)

Why would I begin an Article on imagining the future of law and neuroscience with a brain story nearly two centuries old that others have addressed so many times? One expected answer, of course, is that the past is typically a strong predictor of the future. And the Gage case is a compelling crystal ball. For starters, almost immediately after his injury, Gage became a pawn in contentious debates in science over how the brain works. (22) Today, we recognize that parts of the brain are specialized for particular purposes. (23) But, in the nineteenth century, other scientists held a more holistic perspective, (24) an approach based on the limits of brain science at the time. How and to what extent there were reported changes in Gage's sociabilities would support one scientific view over the other and thus influence the diverging narratives about Gage's brain. (24) These kinds of scientific turf wars certainly exist today, (25) and they will likely become even more pronounced in the future.

In the context of the criminal justice system, for example, experts continuously present testimony driving the narrative about criminal defendants depending on whether they are hired by the prosecution or defense. (27) Deciding which story is most persuasive lies in the hands of the judge or jury. (28) There are also striking parallels between how experts have portrayed Gage over nearly two centuries and how experts in the legal community characterize defendants with brain injuries today. (29) While Gage was never charged or prosecuted for a crime (despite rumors suggesting otherwise), the case remains a metaphor for misunderstandings about brain injured individuals, inside and outside of the law.

The purpose of this Article is to explore how experts have dominated the neuroscience narrative in U.S. criminal cases for twelve decades, from 1900-2020. Stepping back and tracing trends provides perspective on the future of law and neuroscience because "[h]istory, in this sense, is all we have." (30) The discussion focuses on insanity cases because most such cases involve brain damage or abnormality and thus rely heavily on neuroscientific evidence. (31) In addition, for the past 120 years, insanity tests and standards have remained exceptionally stable relative to other criminal law doctrines. (32) The criminal justice system's heavy reliance on scientific or medical experts in insanity cases--irrespective of the type of neuroscientific evidence introduced into court--has also been remarkably fixed. (33) The following discussion contends that, despite the increasing influx of neuroscientific evidence and its purported greater objectivity into the criminal justice system, experts still dominate the narrative of how that evidence, including a defendant's insanity claim, is viewed. While experts are a necessary and invaluable contribution to this process, they can also dangerously distort a defendant's psychological and medical identity; these twists are especially pronounced when the evidence and insanity constructs are ambiguous, as they inevitably are. (34)

To support these arguments, this Article reports the results of my original Twelve-Decade Neuroscience Study (The Study) examining the criminal justice system's use of the insanity defense in all criminal cases--totaling 8,358--involving neuroscientific evidence over the past twelve decades, from 1900 to 2020. Neuroscience--defined generally as "the branch of the life sciences that studies the brain and nervous system"--opened a world of cognitive discovery that often questions the efficacy of established legal doctrines and mores. (35) Given The Study's vast range of data and scope, the timeline of 120 years provides a crucial past and present approach to predict the future of neuroscience.

Part I of this Article discusses the history of the Gage case and its accompanying inaccuracies, noting how early and later expert evaluations of Gage remained fixed and influential over the years despite scientific advances and discoveries about Gage's life. The Gage case also heralded the criminal justice system's increasing reliance on testifying experts, fueling the centrality of the courtroom's "battle of the experts," especially in criminal insanity cases involving neuroscience experts. Part II reviews the origins and development of this country's major insanity tests, as well as The Study's efforts to identify the law and science behind insanity defense trends in the context of fluctuating crime rates. By analyzing The Study's data, Part III examines the nature and extent of the plunging insanity defense rates and the reasons for the decline, including the impact of the 1982 John Hinckley Jr. verdict. The Part also explores The Study's successful post-Hinckley insanity cases and the limited number of circumstances and characteristics in which courts found a defendant insane.

Part IV investigates how The Study's insanity defense narratives use experts in neuroscience to both support and refute insanityrelated claims by employing more sophisticated information to develop a fuller picture of the defendant. While the defense hires experts to help link defendants' mental health problems to their criminal behavior and offer a mitigating narrative for insanity, prosecutors have increasingly relied on accusations of defendant malingering to dispute these strategies. For example, The Study found that malingering issues have increased eight-to-ten fold over the past twelve...