Chapter 1 Notes: An Uneasy Alliance

1.01 The Context for Law and Behavioral Science

• Historical skepticism toward expert witnesses, with a notable 19th-century view that witnesses fell into three classes: "simple liars, damned liars, and experts."¹
• Mental health professionals have been particularly targeted by critics for offering in court what some consider biased or unreliable opinions.
• Public concerns about expert testimony include the belief that some experts peddle "junk science" for a fee, and that flamboyant psychological defenses (e.g., "abuse excuse", "urban survival syndrome") have fueled mistrust.
• Public commentators worry that liberal psychologists use the legal process to influence political judgments; a 1995 NM legislative attempt to require mental health testifyers to wear a cone-shaped hat illustrates the intensity of hostile sentiment (ultimately vetoed).
• Legal professionals have echoed concerns; judges and attorneys have labeled much clinical testimony as "story-telling" and "suppositional" due to a perceived lack of scientific testing of these opinions.
• appellate cases frequently document criticisms of mental health expert morals and objectivity.
• Law schools increasingly offer courses on use of expert social science evidence, reflecting ongoing debate about the admissibility and usefulness of clinical opinions.
• The chapter frames the discussion around how psychological evaluations fit into the legal process, emphasizing that:
  • The law expects incremental rather than absolute validity of expert opinions.
  • Professional credentials alone do not guarantee that opinions will be admissible or helpful.
• The chapter’s purpose is to analyze sources of ambivalence in law–mental health interactions and to address limits of mental health expertise, including who is an expert and for what purposes.

1.02 Some Preliminary Problems in Law and Mental Health

CASE STUDY 1.1

• Setting: Mike Drake is charged with embezzlement; the issue at the criminal trial is whether Drake was insane at the time of the offense under a statutory definition of insanity (mental disease or defect causing substantial inability to appreciate wrongfulness or conform behavior to the law).
• Expert testimony overview at trial:
  • Q: Is the defendant suffering from a gambling disorder?
  • A: Yes; described as a serious problem per DSM-5; multiple psychologists in the field share this view.
  • Q: What led to this diagnosis?
  • A: The defendant admits gambling preoccupation, anxiety when not gambling, and a drastic life stressor including potential job loss.
  • Q: Does this make him incapable of distinguishing right from wrong?
  • A: The expert notes that the individual typically knows the law and right from wrong but is in a desperate situation, with impaired judgment due to gambling urge; cites a study showing elevated crime rates among people with gambling disorder (e.g., 1 in 5 have committed crimes like forgery/theft/embezzlement) versus 1 in 200 in the general population, implying gambling disorder predisposes criminal behavior; advocates treatment over punishment.
  • Q: So would you say he's insane?
  • A: Yes.
• Outcome: Drake acquitted by reason of insanity; committed to an institution for observation.
• Commitment hearing (1 month later): sole hospital witness testifies:
  • Q: What is Drake's condition now?
  • A: Unresponsive to treatment; still dangerous; no guarantee of avoiding future theft to feed gambling habit; cites a study indicating 15–20% of those treated for gambling disorder have attempted suicide.
• Questions posed for analysis (in-class prompts):
  • Apply Frye v. United States test to determine admissibility of linking gambling disorder to insanity.⁽²⁰⁾
  • If admissible, should any statements be legally or ethically prohibited? Should the studies themselves be admissible if accurately described? What additional information about the studies would be helpful? Does jurisdictional adherence to Daubert v. Merrell Dow Pharmaceuticals affect answers?⁽ see § 1.04(c) for Daubert discussion.⁽⁴⁾
• The introduction to this chapter highlights deeper clashes between law and mental health practice, including:
  • Fundamental conceptual differences that are not easily reconciled by training alone (e.g., terminology, methods, epistemology).
  • The need to recognize that the questions the law asks (e.g., culpability, voluntariness) differ from the questions behavioral science answers (e.g., etiology, mechanisms, prognosis).

(a) Bridging Gaps in Training

• Common critique: law and mental health professionals do not "speak the same language," leading to misunderstandings.
• Naive solution would be cross-disciplinary training to translate legal tests into mental health terms and vice versa.
• Authors argue this is naive in the near term: interdisciplinary gaps will persist and there is no quick fix.
• The authors emphasize the need for professionals to understand how the legal system uses questions and issues, and for legal professionals to understand core concepts in behavioral science.
• They condemn two problematic practices:
  • Expert testimony lacking understanding of the legal issue.
  • Legal authorities demanding conclusory opinions without engaging the underlying medical problems.
• There is also emphasis on professional ethics: clinicians should avoid inferring ultimate legal conclusions (e.g., voluntariness, responsibility) and instead provide factual findings and scientific context so factfinders can apply legal standards.
• In Case Study 1.1, the DSM-5 classification of gambling disorder (substance-related and addictive disorders) is noted to align with neurobiological evidence; however, whether behavior was involuntary remains a legal question for the factfinder.

(b) Bridging Attitudinal Differences

• Training alone cannot resolve attitudinal differences between libertarian (civil liberties-focused) and paternalist (treatment-focused) perspectives.
• Therapeutic jurisprudence notes that rules promoting autonomy and those promoting mental health treatment can have similar outcomes, depending on context.
• Attitudes vary within professions (not just between them): for example, the American Psychiatric Association has sometimes advocated for less deference to patient wishes and streamlined decisionmaking, whereas other associations may be more protective of patient autonomy.
• In practice, lawyers also display paternalistic tendencies when dealing with severe mental illness issues (e.g., civil commitments).
• The bottom line: fundamental philosophical positions are deeply embedded and not easily reconciled.

(c) The State of the Art

• The practical source of trouble lies in gaps in scientific knowledge about human behavior and the limited relevance of some psychological findings to specific legal questions.
• Three types of state-of-the-art problems:
  1) Individualized applicability: Legal determinations concern individuals; mental health opinions may be general and not precise enough for individual cases. For example, explaining violent behavior in general is different from explaining a particular act by a specific person.
  2) Gaps between research and legal questions: Researchers know about general effects (e.g., parental divorce on children, cognitive impairments in schizophrenia), but much of this knowledge is not directly applicable to legally relevant questions (e.g., a specific criminal act’s causation or a specific custody decision).
  3) Questions asked by the law that are inherently unanswerable: Some legal questions are too subtle for scientific testing to distinguish, such as the precise impact of a one-week versus two-week visitation change on a child.

1.03 Paradigm Conflicts

This section focuses on how differences in conceptual paradigms between law and the behavioral sciences shape interactions. It answers:

• How might interactions be affected by different problem conceptualizations?
• Do differences in philosophies imply inherent conflict?

(a) Individual Choice versus Biology and Social Influences

• The law is predicated on the idea that people act for reasons, can control themselves, and can be held morally accountable for voluntary actions.

• Behavioral sciences seek to identify causes or influences on behavior that people may not consciously control or even be aware of.

• Illustrative scenario: John Doe, a person with schizophrenia who steals cigarettes from a store. The law tends to view him as someone who can choose to refrain, recognizing his illness but still considering the act as a voluntary wrongdoing.

• For clinicians and neuroscientists, the crucial questions are not just whether the person has a mental illness but why the person acted as they did and what brain mechanisms and environmental factors contributed.

• Neurobiological explanation of Doe’s conduct would emphasize brain pathology (e.g., schizophrenia), nicotine addiction, dopaminergic/glutamatergic dysfunction, and potential comorbidity with smoking as a form of self-medication. These explanations connect brain circuitry and neurochemical processes to self-control and decisionmaking, altering how responsibility might be conceptualized.

• Key neurobiological points include:

  • Schizophrenia involves brain structure abnormalities influencing dopamine/glutamate signaling, which can affect self-control.
  • Nicotine interacts with disturbed pathways, potentially serving as a self-medication mechanism for brain function in schizophrenia.
  • Epigenetic changes from repeated exposure to addictive substances can alter neuronal signaling and stress/reward processing.
  • Social factors (low socioeconomic status, poor parental support) contribute to vulnerability to drug use and crime.

• The resulting neurobehavioral explanation shifts the focus from beliefs and desires to brain processes and information processing, which challenges the traditional legal framework for assigning responsibility.

• Critics question whether organ-level causation can justify replacing intentional action with bio-social causation. The counterargument asserts that all behavior is biological and socially embedded, and thus a strict biosocial account does not by itself distinguish lawful from unlawful behavior.

• The broader position is that humans may be held accountable for actions that are rational or reason-based, but ecological/biological explanations complicate the notion of free will, potentially creating a paradigm conflict between neurobiological explanations and the law’s notions of responsibility.

• The authors conclude that, if clinicians adopt a consistent neurobiological framework, the paradigm within which they operate may inherently conflict with legal ideals. Nevertheless, they suggest a practical path forward: clinicians should avoid giving the ultimate legal conclusion (e.g., “voluntary” vs. “involuntary”) and instead present detailed facts and the scientific context to aid the factfinder in applying the law.

• The text also discusses the risk that clinicians may overly simplify complex data to fit normative legal categories or to satisfy the demands of adversarial legal processes. Clinicians must avoid “pigeonholing” data into narrow legal categories and should recognize the constraints placed on discussing prior offenses or inadmissible hearsay.

• Holmes’ charge: the law relies on precedent and formal rules to protect stable social values, which may lead to conservative interpretations that can obscure modern empirical findings. If judges rely on empirical findings, they should explicitly state the empirical basis for their conclusions rather than rely on policy preferences or untested assumptions.

• The “ultimate-issue” problem: whether the defendant’s acts were voluntary or a product of mental illness remains a legal question; clinicians can discuss factors that influence decisions but should leave ultimate legal conclusions to the trier of fact.

• The authors emphasize that the forensic process is distinct from clinical treatment: the purposes of forensic evaluations are not identical to clinical assessments for treatment.

(b) The Process of Factfinding

• The adversary system can clash with the collaborative, nonadversarial ethos of clinical practice. Mental health professionals often prefer cooperative approaches and may be uncomfortable with the adversarial litigation framework.
• Forensic work requires professionals to understand that the legal process seeks not only truth but also justice (due process, fair opportunity for both sides to present evidence).
• Clinicians should maintain intellectual integrity, avoid tailoring opinions to the party that retains them, and be upfront about the limits of their observations and expertise.
• Observations can be “pigeonholed” into legal categories that strip data of richness (e.g., focusing on desires and beliefs rather than social/contextual factors).
• Legal rulings may restrict discussion of prior crimes or admissible hearsay; these constraints can impede fully informed clinical opinions.
• The law is inherently conservative, aiming for continuity with past legal practices to preserve stability and fairness in the administration of justice. For example, homicide law often centers on premeditation, and past crime rules limit what may be admitted to avoid convicting someone for past conduct rather than the current charge.
• When empirical findings are relied upon, judges should differentiate policy preferences from empirical evidence; otherwise, decisionmaking can be unjust or biased.
• The potential danger of overreliance on normative or historical values can lead to misalignment with the real-world functioning of people and the social contexts in which they live.

(c) The Nature of a Fact

• The two disciplines conceptualize “fact” differently, which affects how probabilistic information is used in legal decisionmaking.

(1) From Probability to Certainty

• The sciences are inherently probabilistic, but the law demands the appearance of certainty due to the high stakes of decisionmaking.
• The burden of proof in law is probabilistic in nature until it is met, after which the decision is made with finality (guilty or not).
• Example: a civil engineering assessment for a bridge might yield a high probability that a component (e.g., steel rods) is below a required width under certain conditions, but legally the fact to be decided is whether the rods were too small, not the probability of error.
• Problems arising from probabilistic testimony in law include: forced odds about guilt, potential misinterpretation by jurors, and perceptions that probabilistic statements are less credible when presented in a non-nominal way.
• Ethical guidelines for forensic psychologists/psychiatrists require clear communication of uncertainty; overconfidence in opinions beyond what the data warrant should be avoided, even if it reduces the weight of testimony.
• Clinicians often present idiographic (case-centered) conclusions, which courts may prefer, but this creates a tension with the probabilistic, nomothetic (group-based) research base.
• Courts often accept declarative, categorical statements of irrationality or reasonableness, but probabilistic statements about likelihoods (e.g., percentages) may be less persuasive.
• Even if probabilistic information is accepted, there is a risk that it will be given undue weight to bolster the state’s case, or that judges will treat certainty as a proxy for accuracy.
• Some jurisdictions attempt to convert probabilistic judgments into certainties via standards like "reasonable medical certainty" for admissibility; however, even expert opinions deemed uncertain can have probative value if not prejudicial.

(2) From Group to Individual (G2i)

• Scientific knowledge often derives from group-level data; applying those nomothetic findings to a specific individual can be problematic.

• The chapter gives concrete examples illustrating G2i challenges:

  • Case 1.68: A 14-year-old daughter recants an incest claim; later testifies inconsistently. Experts state that such inconsistency is common among incest victims.
  • Case 2.69: A defendant charged with third-degree murder; an expert claims battered-child syndrome and links to parental abuse; defendant’s past caseworker and school staff provide corroborating or conflicting personality and history data.
  • Case 3.70: A defendant stopped by DEA due to drug-currier profile; evidence suggests that behavioral profiling can lead to searches, with concerns about reliability and evidentiary standards.
  • Case 4.71: A civil commitment case involving a sexual predator; risk assessment predicts a 58% risk of future violence; the defense argues the profile incorporated parental alcoholism and schizophrenia is not applicable given reformation and treatment.

• These cases illustrate the difficulty of relying on probabilistic generalizations to determine past, present, or future guilt or risk for an individual.

• Tribe’s critique argued that precision probabilities should be barred in law due to several concerns (e.g., probabilities themselves are uncertain, interdependencies exist, and risk of prejudice).⁽¹⁶⁾

• Saks and Kidd provide critique and argue that jurors process probability information and can benefit from presenting actual probabilities rather than abstract precision.⁽⁸⁰⁾

• The authors acknowledge that all evidence is probabilistic in the end; the key is to present accurate probabilistic information and ensure it is legally cognizable and not prejudicial.

• The text also discusses two important cautions regarding probabilistic evidence in criminal contexts:

  • The use of factors beyond the defendant’s control (e.g., parental alcoholism, schizophrenia) in actuarial risk assessments and sentencing can raise constitutional and ethical concerns.
  • The potential for probabilistic information to override direct evidence or to lead to prejudicial outcomes if not contextualized properly.

• The authors conclude that, while probabilistic evidence can be informative, it must be carefully framed within the legal standards and the evidentiary rules governing admissibility and weight.

• In sum, 1.03 emphasizes that there are deep philosophical and methodological divides between law and the behavioral sciences, driven by differences in:

  • Conceptualization of human agency and causation (intentional action vs. biological/social determinants).
  • Determination of what counts as a fact and how to weigh probabilistic information.
  • The adversarial process and the legal system’s emphasis on precedent, rules of evidence, and justice over truth alone.

1.04 (Not provided in the excerpt)

• The excerpt references additional discussions on Frye v. United States and Daubert v. Merrell Dow Pharmaceuticals as they relate to admissibility, suggesting that these cases will be discussed further in § 1.04(c). The present notes summarize the primary ideas up to § 1.03 and point to these cases as part of the ongoing discussion about standards for admitting expert testimony.

Key concepts and terms to remember

• Incremental validity: In legal contexts, a new expert opinion need not be absolutely correct; it should add useful information beyond existing evidence to aid decisionmaking.
• M'Naghten test: A historic insanity standard focusing on whether the defendant knew right from wrong, which has been criticized for being too narrow.
• Durham v. United States: A case that shifted focus from moral and cognitive knowledge to the character of the defendant's mental disorder; later deemed to be limited due to fundamental epistemological differences.
• Daubert v. Merrell Dow Pharmaceuticals: A later standard for admitting expert testimony (not described in detail in the excerpt, but referenced as a future discussion).
• Frye v. United States: A standard for admissibility focusing on general acceptance in the relevant scientific community (as discussed in relation to the admissibility of clinical testimony linking gambling disorder to insanity).
• “Story-telling” / “suppositional” testimony: Pejorative labels used to criticize clinical opinions that are not empirically tested.
• Forensic evaluation versus clinical treatment evaluation: Distinct purposes; forensic work informs legal decisionmaking, while treatment aims at patient care.
• G2i (General-to-Individual): The challenge of applying group-derived research findings to a specific person.
• Reasonable certainty: A legal standard sometimes used to gauge admissibility or weight of expert testimony, which can obscure the probabilistic nature of scientific conclusions.
• Base rates and base-rate fallacy: The risk that statistial information about a population does not translate directly to an individual case without considering base rates (as illustrated in Case 1.1 and the MMM example).
• Phenomena of neurobiological explanations for behavior: Brain pathology, neurotransmitter systems, epigenetic changes, and social determinants all contributing to behavior and potentially to legal responsibility debates.

Important equations and numerical references (LaTeX)

• Population and base-rate example (Table 1.1):
  • Total children and youth: $N = 74{,}000{,}000$
  • Proportion recently sexually abused: $p_{ab} = 0.05$
  • Number recently abused: $N<em>{ab} = N imes p</em>{ab} = 74{,}000{,}000 imes 0.05 = 3{,}700{,}000$
  • Proportion who fit the MMM profile among abusers: $q = 0.90$
  • True positives: $TP = N_{ab} imes q = 3{,}700{,}000 imes 0.90 = 3{,}330{,}000$
  • Non-abused population: $N_{not} = 74{,}000{,}000 - 3{,}700{,}000 = 70{,}300{,}000$
  • Proportion who fit the MMM profile among non-abused: $r = 0.10$
  • False positives: $FP = N_{not} imes r = 70{,}300{,}000 imes 0.10 = 7{,}030{,}000$
  • Total positives: $TP + FP = 3{,}330{,}000 + 7{,}030{,}000 = 10{,}360{,}000$
  • Positive predictive value (probability that someone fitting the MMM profile has been abused): $PPV = \frac{TP}{TP+FP} = \frac{3{,}330{,}000}{10{,}360{,}000} \approx 0.321\approx 32.1\%.$
• These calculations illustrate how base rates affect interpretation of probabilistic testimony and the risk of base-rate neglect in court.

Practical implications for exam preparation

• Expect questions about the tension between law and psychology/psychiatry: What can be reliably claimed about individuals versus groups? How should probabilistic information be presented? What are the limits of expert testimony when it comes to ultimate legal conclusions?
• Be prepared to discuss the evolution of insanity standards (M'Naghten, Durham) and why newer approaches emphasize the character of the mental disorder rather than strict knowledge of right and wrong.
• Understand the distinction between forensic and clinical evaluations, and why the legal process requires a balance between truth-seeking and justice/fairness.
• Be able to identify and articulate the G2i challenge and apply it to example cases, including the base-rate issues demonstrated in Table 1.1.
• Recognize the ethical responsibility of experts to report uncertainty and avoid overstatement of certainty in opinions.

2. Key terms recap (quick reference)

• Incremental validity, not absolute validity
• M'Naghten test, Durham test
• Frye v. United States, Daubert v. Merrell Dow Pharmaceuticals
• Story-telling and suppositional testimony
• Forensic evaluations vs. treatment evaluations
• General-to-Individual (G2i) problem
• Reasonable certainty, probabilistic reasoning in court
• Base rates, base-rate fallacy, predictive value