Expert Psychological Testimony for the Courts

Mark Costanzo, Daniel Krauss, Kathy Pezdek, Mark Costanzo, Daniel Krauss, Kathy Pezdek

• Publisher: Psychology Press
• Year: 2020
• ISBN:
  9781000149425
• Edition: 1
• Topic: Psychology
• Subtopic: History & Theory in Psychology
• Index: Psychology

During the past two decades, the frequency and range of expert testimony by psychologists have increased dramatically. Courts now routinely hear expert testimony from clinical, cognitive, developmental, and social psychologists. Expert Psychological Testimony for the Courts provides a comprehensive, research-based analysis of the content, ethics, and impact of expert testimony. This book features leading scholars who have contributed to the scientific foundation for expert testimony and who have also served as expert witnesses. The opening chapter explores issues surrounding the admissibility of expert testimony, and the closing chapter explores the ethics and limits of psychological testimony. Each of the intervening chapters focuses on a different area of expert testimony: forensic identification, police interrogations and false confessions, eyewitness identification, sexual harassment, mitigation in capital cases, the insanity defense, battered women, future dangerousness, and child custody. These chapters describe the typical content of expert testimony in a particular area, evaluate the scientific foundation for testimony, examine how jurors respond to expert testimony, and suggest ways in which legal standards or procedures might be modified in light of psychological research. This groundbreaking book should be on the shelf of every social scientist interested in the legal system and every trial attorney who is likely to retain a psychologist as an expert witness. It can also serve as a text for advanced courses in psychology, legal studies, criminal justice, law, and sociology.

1

Varieties and Vagaries of Expert Psychological Testimony: An Introduction

Mark Costanzo
Daniel Krauss

Claremont McKenna College

Kathy Pezdek

Claremont Graduate University

During the past two decades, the frequency and range of expert testimony by psychologists have increased dramatically. Twenty years ago, nearly all such testimony involved clinical psychologists offering their assessments of particular defendants, especially in such areas as competence to stand trial and insanity. Although these traditional clinical areas remain important, courts now routinely hear expert testimony from cognitive, developmental, and social psychologists. The increasing prominence of expert psychological testimony appears to be the result of two factors: the rapidly expanding research base in areas of interest to the courts, and changes in the legal standards governing the admissibility of scientific evidence.

This book brings together leading scholars who have contributed to the scientific foundation of expert testimony and who have also served as expert witnesses. Chapter 2 provides an overview of issues surrounding the admissibility of expert testimony, and chapter 12 explores the ethical and practical dilemmas faced by psychological experts who testify in court. Each of the nine intervening chapters focuses on a different area of expert testimony. These areas include forensic identification evidence, interrogations and potentially false confessions, eyewitness memory and identification, sexual harassment, mitigation testimony in death penalty cases, the insanity defense, battered woman syndrome, prediction of future dangerousness, and child custody evaluations. For all but chapters 2 and 12, the authors were asked to address the following four questions:

1. What is typically the content of expert testimony on ______?
2. How strong is the scientific foundation for expert testimony on _______ ?
3. Is there research on how jurors respond to expert testimony on _______?
4. How might the legal system (e.g., procedures, standards, instructions) be modified in light of psychological research on ______?

The chapters that follow show the broad range and varied content of expert testimony offered by psychologists. In addition to reviewing the research evidence that serves as the basis for testimony, each chapter also explores how the courts have responded and should respond to research and expert testimony.

In chapter 2, Bruce Sales and Daniel Shuman examine how the courts decide whether expert testimony by psychologists will be admitted into evidence. Until the late 20th century, trial court evidentiary decisions had rarely been the basis for an appeal, let alone the grounds for a successful appeal. However, beginning in 1993, in a series of decisions addressing the admissibility of experts in federal court under the law of evidence, in Daubert v. Dow Pharmaceutical, Inc. (1993) and two subsequent cases, General Electric v. Joiner (1997) and Kumho Tire Co. v. Carmichael (1999), the Supreme Court precipitated more attention to the admissibility of expert testimony than had occurred in the preceding 250 years. Sales and Shuman consider the reasons for this change in emphasis and concern, the problems that the law revision has encountered and is likely to encounter in judicial administration, and potential solutions to these conceptual and practicable dilemmas.

In chapter 3, William Thompson and Simon Cole consider how psychological processes influence the interpretation of physical evidence such as fingerprints and DNA. Forensic identification evidence seeks to identify the source of a physical trace, such as biological material or the impression of a body or object. Forensic scientists often make source attributions–that is, determinations that items of physical evidence have (or might have) a common source. Expert testimony about source attributions is a common feature of modern criminal trials. Thompson and Cole examine the judgment and decision-making process experts use to make source attributions in various forensic disciplines, and identify four common ways experts characterize those determinations: simple match (no statistics), match plus statistics, qualitative assessment of certainty, and individualization. Their chapter discusses the strength of the scientific foundation for such testimony, comparing the relatively strong validation for DNA evidence with the weaker (or nonexistent) validation for other forensic disciplines. Thompson and Cole review research on jurors’ reactions to forensic testimony and discuss possible legal reforms that could strengthen the quality of expert forensic testimony and reduce the likelihood that it will be presented in a misleading manner.

Chapter 4 explores research and testimony on police interrogation and false confessions. Recent exonerations of prisoners because of DNA evidence have revealed that the number of convictions based on false confessions is much higher than previously supposed. Mark Costanzo and Richard Leo explore why a false confession might appear credible to judges and jurors, and describe the types and dynamics of false confessions. They propose a person-situation analysis that describes how suspect risk factors (youth, mental retardation, mental illness, temporary impairments, and vulnerable personality) can interact with factors in the interrogation process (control, social isolation, certainty of guilt, minimization of culpability, and faulty interpretation of suspect behavior) to produce false confessions. Finally, Costanzo and Leo discuss the admissibility and content of expert testimony on interrogations and confessions and describe several ways of reducing both the occurrence and impact of false confessions.

Expert testimony on eyewitness memory and identification is the subject of chapter 5. During the past decade, it has become clear that faulty eyewitness evidence has been the major source of evidence used to convict innocent people who were later exonerated based on forensic DNA. Yet, ironically, jurors tend to find eyewitness testimony especially compelling. Kathy Pezdek argues that one way to assist jurors in evaluating eyewitness evidence more accurately is to present the testimony of an expert witness on the fallibility of eyewitness memory and identification. The role of the eyewitness expert witness is described, the scientific foundation for eyewitness expert testimony is summarized, and the response of typical jurors to such testimony is presented. Given the fertile nature of scientific research on the psychological factors that influence eyewitness memory, eyewitness expert witnesses are increasingly likely to be called on to consult with legal professionals and to testify in court. The chapter ends with several suggestions for modifying the legal system in light of the psychological research on eyewitness memory and identification.

Psychologists have played a role in many sexual harassment cases, testifying on such issues as the mental health consequences of sexual harassment, the social and organizational climate in which sexual harassment is most likely to occur, and the reasons why a target of such behavior might or might not complain about harassing behavior. In chapter 6, Maureen O’Connor examines this testimony and the research that supports it. Given the nature of the adversary system, psychologists testify on both sides of sexual harassment cases, often leading to a battle of the experts that can call into question the utility of the psychological information for those tasked with deciding the case. Some of these battles have been quite heated and raise interesting questions about the role of expert witnesses in the legal system. O’Connor examines the scope of the psychological knowledge that experts have brought to bear in sexual harassment cases, the limits of that knowledge, some of the important battles that have occurred in sexual harassment cases, and the extent to which such testimony affects juror decision making.

The presentation of mitigating evidence in the penalty phase of a capital trial is not meant to justify or diminish the significance of a murder, but to explain criminal behavior in a way that is useful to capital jurors making a sentencing decision. In chapter 7, Karen Salekin explains how mitigation evaluations are conducted and what information might be useful to jurors. The basic procedure consists of conducting a thorough investigation of the defendant’s life in an effort to reveal influential factors in the developmental process. Despite robust findings regarding the viability of risk factors and protective factors, research has indicated that this information may not be conveyed very effectively to capital jurors. Jurors are not equipped to use this information, are confused by their legal charge in these proceedings, and lack effective guidance about how to weigh mitigating circumstances against aggravating circumstances. Other problems may also interfere with jurors’ understanding of mitigation evidence. For example, the very process of death qualification may preclude a juror from considering mitigating circumstances, and jurors may view psychological testimony presented in these hearings as biased and therefore give it little weight. Salekin suggests ways that psychologists can inform courts of the research basis for psychological testimony and discusses potential ways that research in psychology can contribute to mitigation evidence in capital cases.

Expert testimony on the insanity defense is the subject of chapter 8. Norman Finkel examines the expert psychological testimony proffered in two recent high-profile insanity cases: those of Andrea Pia Yates and of Lee Boyd Malvo. In both cases, multiple experts testified, reaching not only divergent but highly suspect conclusions about each defendant’s state of mind and whether he or she knew right from wrong. Finkel argues that expert psychological conclusions occur within a legal context that places constraints—some new (“the law’s madness”) and some quite old (“insanity’s disconnect”)—on the telling of the story. Thus, what may appear to be “the irresistible impulses of experts” to exceed scientific and legal constraints may not be the whole story. When expert testimony is examined within these larger contexts, certain types of “mistaken opinions” take on a new psychological and legal significance. In the end, the disciplines of psychology and law may be further apart with regard to the essence of insanity than they were in 1800. Consequently, creating a test for insanity that is consistent, coherent, valid, and worthy of respect seems to be a fading dream.

Because jurors often harbor misinformation about battered women and the battering context, expert testimony pertaining to battered woman syndrome is often admitted in trials of battered women who have killed their abusers. Regina Schuller and Gwen Jenkins explore this topic in chapter 9. Since its first entry into the courtroom in the late 1970s, battered woman syndrome testimony has been used with some frequency in the United States, Canada, Australia, and New Zealand. Although the admissibility of the testimony was heralded as a landmark victory for battered women (indeed, the impetus it provided for the courts’ eventual acknowledgment of the obstacles confronting a battered woman’s claim of self-defense represents a significant legal achievement), concerns regarding its use were quickly voiced. In particular, the testimony, which describes the common patterns found in battering relationships and its impact on a woman, has been criticized on the grounds that it focuses on the woman’s passivity and portrays a singular profile of battered women. This view is at variance with the varied reactions and responses of battered women. Schuller and Jenkins first outline the content of the testimony, with particular attention given to its scientific validity. Following this, they review research on the impact of such testimony, and conclude with a reformulation of expert testimony that focuses on the social reality of the battered woman’s situation as opposed to her psychological reactions to the abuse.

The U.S. legal system relies heavily on experts’ ability to differentiate between individuals who will and will not commit future crimes. This occurs in a variety of legal settings including: capital sentencing, civil commitment of sexual offenders and the mentally ill, and pretrial detention of criminal defendants. In chapter 10, Daniel Krauss and Joel Lieberman explore testimony on future dangerousness. Expert predictions may be based on “unstructured clinical judgments” in which experts intuitively combine information that they believe will be predictive of future dangerousness, or on “actuarial” instruments that indicate exactly how specific empirically verified risk factors should be combined. Krauss and Lieberman discuss the scientific basis for both clinical and actuarial assessments and describe a more recent approach known as “guided professional judgments” that combines the benefits of clinical and actuarial approaches. Using expert testimony in capital murder trials as an exemplar, they discuss the legal basis for admitting future dangerousness testimony (under the Frye and Daubert standards) and the predictive limitations of such testimony. They also present a theoretical explanation for why jurors tend to inappropriately give greater weight to clinical testimony over actuarial testimony. They conclude with a discussion of policy implications and recommendations for procedural changes that courts could adopt to reduce problems associated with future dangerousness testimony.

When separating or divorcing parents are unable to reach an agreement regarding custody of their children, such decisions must be made by the court, in consideration of “the best interests of the children.” In chapter 11, Randy Otto and David Martindale explore how this important decision is made. In many contested custody cases, judges and attorneys ask psychologists (as well as other mental health professionals) to assess members of the dissolving family. These requests are predicated on assumptions that: (a) such decisions involve consideration of a number of factors that are psychological in nature; (b) psychologists and other mental health professionals, as a function of their specialized knowledge, training, and experience, are able to offer information and insights about the parties and their children that the court might not otherwise have or consider; and (c) provision of this information will result in more accurate legal decisions and better outcomes for children and their parents. Otto and Martindale critique existing legal standards for child custody decision making, and propose more workable alternatives. Next, evaluation practices of mental health professionals who conduct such evaluations are discussed. Finally, the scientific basis for expert testimony offered by psychologists and other mental health professionals is reviewed, and recommendations for defensible practice are offered.

In chapter 12, Michael Saks and Richard Lanyon explore the dilemmas and ethical conflicts that often arise when experts testify in court. The task of being a competent and ethical expert witness is difficult for a variety of reasons. The most challenging dilemma is presented by the structure of the role of the expert, which confronts such witnesses with an inherent role conflict. This role evolved into its contemporary form as the legal process grew adversarial in the latter part of the 18th century, resulting in a shift of control over witness selection, preparation, and presentation from judges to advocates. First, Saks and Lanyon explore the ethical implications of this role structure. Next, they discuss the most serious and common pitfalls of being an expert witness—as a matter of both ethics and competence—and how to avoid them.

Together these chapters illuminate most of the areas in which psychologists serve as expert witnesses, highlight areas where there are gaps in our knowledge base, and suggest ways of enhancing the application of psychological research to important legal issues. The increased prominence of expert psychological testimony in the courts and the reduction of barriers between the disciplines of psychology and law are welcome opportunities that can benefit both fields and the vast number of people they serve.

References

1. Daubert v. Dow Pharmaceutical, Inc., 509 U.S. 579 (1993).
2. Frye v. United States, 293 F. 1013 (D.C. Cir. 1923).
3. General Electr iv. Joiner, 522 U.S. 136 (1997).
4. Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999).

2

Science, Experts, and Law: Reflections on the Past and the Future*

Bruce D. Sales

University of Arizona
Daniel W. Shuman

Southern Methodist University

The admissibility of expert testimony in court is an issue assigned to trial court judges. When their admissibility decisions are appealed, the traditional rules that govern the scope of appellate review of trial court evidentiary decisions has resulted in appellate court deference to trial court decisions about the admissibility of expert testimony. This is done for at least two reasons. First, it avoids destabilizing trial court decisions. A trial judg...

Table of contents

• Cover
• Half Title
• Series Page
• Title Page
• Copyright Page
• Table of Contents
• 1 Varieties and Vagaries of Expert Psychological Testimony: An Introduction
• 2 Science, Experts, and Law: Reflections on the Past and the Future
• 3 Psychological Aspects of Forensic Identification Evidence
• 4 Research and Expert Testimony on Interrogations and Confessions
• 5 Expert Testimony on Eyewitness Memory and Identification
• 6 Expert Testimony in Sexual Harassment Cases: Its Scope, Limits, and Effectiveness
• 7 Capital Mitigation From a Developmental Perspective: The Importance of Risk Factors, Protective Factors, and the Construct of Resilience
• 8 Insanity’s Disconnect, the Law’s Madness, and the Irresistible Impulses of Experts
• 9 Expert Evidence Pertaining to Battered Women: Limitations and Reconceptualizations
• 10 Expert Testimony on Risk and Future Dangerousness
• 11 The Law, Process, and Science of Child Custody Evaluation
• 12 Pitfalls and Ethics of Expert Testimony
• Author Index
• Subject Index
• About the Authors