We integrate multiple domains of psychological science to identify, better understand, and manage the effects of subtle but powerful biases in forensic mental health assessment. This topic is ripe for discussion, as research evidence that challenges our objectivity and credibility garners increased attention both within and outside of psychology. We begin by defining bias and provide rich examples from the judgment and decision making literature as they might apply to forensic assessment tasks. The cognitive biases we review can help us explain common problems in interpretation and judgment that confront forensic examiners. This leads us to ask (and attempt to answer) how we might use what we know about bias in forensic clinicians’ judgment to reduce its negative effects.

We conducted an international survey in which forensic examiners who were members of professional associations described their two most recent forensic evaluations (N=434 experts, 868 cases), focusing on the use of structured assessment tools to aid expert judgment. This study describes:

1. The relative frequency of various forensic referrals.
2. What tools are used globally.
3. Frequency and type of structured tools used.
4. Practitioners’ rationales for using/not using tools.

We provide general descriptive information for various referrals. We found most evaluations used tools (74.2%) and used several (on average 4). We noted the extreme variety in tools used (286 different tools). We discuss the implications of these findings and provide suggestions for improving the reliability and validity of forensic expert judgment methods. We conclude with a call for an assessment approach that seeks structured decision methods to advance greater efficiency in the use and integration of case-relevant information.

This survey of 206 forensic psychologists tested the “filtering” effects of preexisting expert attitudes in adversarial proceedings. Results confirmed the hypothesis that evaluator attitudes toward capital punishment influence willingness to accept capital case referrals from particular adversarial parties. Stronger death penalty opposition was associated with higher willingness to conduct evaluations for the defense and higher likelihood of rejecting referrals from all sources Conversely, stronger support was associated with higher willingness to be involved in capital cases generally, regardless of referral source. The findings raise the specter of skewed evaluator involvement in capital evaluations, where evaluators willing to do capital casework may have stronger capital punishment support than evaluators who opt out, and evaluators with strong opposition may work selectively for the defense. The results may provide a partial explanation for the “allegiance effect” in adversarial legal settings such that preexisting attitudes may contribute to partisan participation through a self-selection process.

Examinations of trust have advanced steadily over the past several decades, yielding important insights within criminal justice, economics, environmental studies, management and industrial organization, psychology, political science, and sociology. Cross-disciplinary approaches to the study of trust, however, have been limited by differences in defining and measuring trust and in methodological approaches. In this chapter, we take the position that: 1) cross-disciplinary studies can be improved by recognizing trust as a multilevel phenomenon, and 2) context impacts the nature of trusting relations. We present an organizing framework for conceptualizing trust between trustees and trustors at person, group, and institution levels. The differences between these levels have theoretical implications for the study of trust and that might be used to justify distinctions in definitions and methodological approaches across settings. We highlight where the levels overlap and describe how this overlap has created confusion in the trust literature to date. Part of the overlap – and confusion – is the role of interpersonal trust at each level. We delineate when and how interpersonal trust is theoretically relevant to conceptualizing and measuring trust at each level and suggest that other trust-related constructs, such as perceived legitimacy, competence, and integrity, may be more important than interpersonal trust at some levels and in some contexts. Translating findings from trust research in one discipline to another and collaborating across disciplines may be facilitated if researchers ensure that their levels of conceptualization and measurement are aligned, and that models developed for a particular context are relevant in other, distinct contexts.

This chapter integrates from cognitive neuroscience, cognitive psychology, and social psychology the basic science of bias in human judgment as relevant to judgments and decisions by forensic mental health professionals. Forensic mental health professionals help courts make decisions in cases when some question of psychology pertains to the legal issue, such as in insanity cases, child custody hearings, and psychological injuries in civil suits. The legal system itself and many people involved, such as jurors, assume mental health experts are “objective” and untainted by bias. However, basic psychological science from several branches of the discipline suggest the law’s assumption about experts’ protection from bias is wrong. Indeed, several empirical studies now show clear evidence of (unintentional) bias in forensic mental health experts’ judgments and decisions. In this chapter, we explain the science of how and why human judgments are susceptible to various kinds of bias. We describe dual-process theories from cognitive neuroscience, cognitive psychology, and social psychology that can help explain these biases. We review the empirical evidence to date specifically about cognitive and social psychological biases in forensic mental health judgments, weaving in related literature about biases in other types of expert judgment, with hypotheses about how forensic experts are likely affected by these biases. We close with a discussion of directions for future research and practice.

This study sought to investigate the relation between expert witness likeability and juror judgments of credibility and sentencing. Two actors playing expert witnesses were trained to present themselves as high and low in likeability in a standard testimony scenario involving capital trial sentencing. The effects of extraversion and gender in mock jurors in attending to expert testimony were also examined. The dependent variables were the perceptions of the witnesses’ credibility and agreement with testimony and the participants were 210 psychology undergraduates. Likeability of expert witnesses was found to be significantly related to judgments of trustworthiness of the experts, but not related to confidence or knowledge of the experts or to the mock juror sentencing decisions. Women participants rated high likeable experts as more credible than low likeable experts; men did not. For men jurors, agreement with testimony increased as extraversion increased. However, for women jurors, agreement with testimony decreased as extraversion increased. The results suggest that likeability can be an important element of source credibility, and that attorneys and trial consultants now have an empirical foundation for addressing likeability as part of witness preparation.

Prisoners sentenced to death must be competent for execution before they can actually be executed (Ford v. Wainwright, 1986). The decision for many mental health professionals whether to conduct competence for execution evaluations may be fraught with complex ethical issues. Mental health professionals who do not personally support capital punishment may have a particularly difficult decision to make in this regard but should seriously consider the consequences of their decisions. This article applies Bush, Connell, and Denney’s (2006) eight-step ethical decision-making model to the ethicality of deciding to or abstaining from conducting competence for execution evaluations. This article does not propose what decisions an individual evaluator should make regarding this work, but rather presents a systematic guide for mental health professionals (particularly those who do not support capital punishment) to consider.