What Should I, as a Forensic Psychologist Specializing in Violence Risk Assessment, Understand About Case Law Shaping Assessment Standards?

As forensic psychologists, we are often asked to provide opinions that affect a person’s liberty, including civil commitment, continued confinement, or conditional release. Courts rely on violence risk assessments to inform these decisions, but they also scrutinize the legal legitimacy of the methods and reasoning underlying those opinions.

Case law shapes:

• What constitutes legally relevant dangerousness: Courts define the types of risk that are legally meaningful, often requiring a nexus between an individual’s mental condition, their behavior, and the likelihood of serious harm. Case law clarifies that not all risk is sufficient to justify deprivation of liberty, shaping how forensic psychologists conceptualize and describe dangerousness.
• How prediction may be framed without violating due process: Judicial decisions limit how opinions about future violence can be expressed, emphasizing probabilistic language and cautioning against claims of certainty. Case law reinforces that violence risk evaluations inform, rather than determine, legal outcomes and must be framed in a manner consistent with due process protections.
• The limits of expert opinion regarding future violence: Courts place boundaries on the scope of expert testimony, distinguishing between informing the court about risk factors and opining on ultimate legal questions. Case law helps delineate what experts may appropriately conclude versus what remains the court’s responsibility to decide.
• Professional liability when assessments are later challenged: Judicial review of past cases highlights circumstances in which evaluators may face legal or professional consequences for flawed methods, overreached conclusions, or failure to follow accepted standards. Understanding this body of law helps forensic psychologists anticipate and mitigate risks associated with scrutiny of our work. Understanding these legal boundaries enables us, as forensic psychologists, to conduct violence risk assessments that are scientifically grounded and constitutionally defensible.

How Does Case Law Shape the Use of Risk Assessment Tools for Forensic Psychologists Specializing in Risk Evaluation?

Courts rarely require the use of specific violence risk assessment instruments. Instead, case law emphasizes whether the methods employed are reliable, relevant to the legal question, and transparently applied. Admissibility and credibility depend less on the tool selected than on whether the forensic psychologist can demonstrate that the tool was appropriate for the referral question and used in accordance with accepted professional standards.

Accordingly, evaluators are expected to use instruments as designed, interpret results within the broader clinical and legal context, and ensure that scores inform, rather than substitute for, reasoned risk formulation. Case law makes clear that tools do not speak for themselves; courts privilege defensible reasoning that clearly links data, methodology, and conclusions.

As forensic psychologists, we must do more than identify risk factors. Case law requires that we articulate why an individual’s characteristics meaningfully increase the risk of violence in a manner that justifies state intervention. In practice, courts expect risk opinions to be legally grounded, methodologically sound, and transparently reasoned.

Specifically, case law requires forensic psychologists to:

• Legally anchor our risk opinions: Identifying risk factors is insufficient. Courts expect evaluators to explain how a legally recognized mental condition contributes to impaired behavioral control and increases risk in a way that justifies intervention.
• Offer bounded and defensible predictions: Supreme Court precedent permits risk-based opinions only when they are probabilistic, evidence-based, and tied to specific mechanisms of risk. Overstated certainty or global conclusions invite challenge.
• Use assessment tools as frameworks, not verdicts: Risk assessment instruments such as the Historical, Clinical, Risk Management–20 (HCR-20) and Psychopathy Checklist–Revised (PCL-R) may inform risk formulation, but they do not establish dangerousness on their own. High scores or the presence of multiple risk factors require careful interpretation and cannot substitute for articulated reasoning.
• Recognize that tool stacking does not equal rigor: Pairing multiple instruments without a clear justification increases the risk of double-counting and undermines methodological defensibility under legal scrutiny.
• Explicitly state limitations: Courts increasingly scrutinize whether experts acknowledge data constraints, measurement error, and the boundaries of what an assessment can conclude. Failure to do so is a credibility risk. When these boundaries are left unstated, opinions can appear overstated or scientifically careless. Explicitly addressing limitations does not weaken an assessment. It demonstrates methodological competence, transparency, and respect for the court’s decision-making role. In contrast, failing to do so creates an easy credibility vulnerability on cross-examination. In today’s legal landscape, clarity about what an assessment can and cannot conclude is a marker of expert credibility, not a disclaimer.
• Remain jurisdictionally informed: Statutes and case law vary widely across states. Competent practice requires familiarity with local legal definitions, standards of proof, and procedural requirements that shape how risk opinions are evaluated.

Case law also illustrates how failures in these areas can give rise to professional liability. In Jablonski by Pahls v. United States (1983), the Ninth Circuit held that a clinician’s failure to consider available prior records, resulting in an incomplete evaluation of dangerousness, could constitute negligence. The case is frequently cited in risk assessment jurisprudence because it underscores the professional duty to conduct thorough, contextually grounded evaluations.

Similarly, Daubert-related jurisprudence, including Kumho Tire Co. v. Carmichael (1999), reinforces that the admissibility of expert testimony turns on the reliability of the methodology and reasoning, not on credentials or professional consensus alone. For forensic psychologists, this means that how risk opinions are developed and explained is often more consequential than the specific tools employed.

What Professional Liability Risks Arise for Forensic Psychologists Specializing as Expert Witnesses Who May Ignore Case Law?

Failure to account for relevant case law exposes forensic psychologists to significant professional and legal risk. Evaluations that exceed constitutional limits, mischaracterize legally relevant dangerousness, or rely on unsupported assumptions may be challenged long after they are completed—often in contexts where the evaluator no longer controls how their work is interpreted.

These risks include exclusion of testimony, ethical complaints, and lasting damage to professional credibility. Legal literacy should therefore be understood not as a separate legal skill, but as a core component of competence in violence risk assessment, protecting both the individuals evaluated and the forensic psychologist’s professional integrity.

Several landmark U.S. Supreme Court cases define the constitutional parameters of SVP commitment and, by extension, the expectations placed on forensic psychologists conducting violence risk assessments.

In Kansas v. Hendricks (1997), the Court upheld civil commitment statutes targeting individuals with a mental abnormality or personality disorder associated with future dangerousness. Importantly, the Court emphasized that commitment was not punishment, but was to address treatment needs, and that expert testimony regarding risk played a central role.

As forensic psychologists, we must recognize that Hendricks does not authorize limitless prediction. Instead, it requires that risk opinions be grounded in:

• A legally cognizable mental condition
• Evidence linking that condition to impaired behavioral control
• A rational connection between diagnosis and dangerousness

Subsequent cases, including Kansas v. Crane (2002), clarified that a total lack of control is not required, but some degree of volitional impairment must be demonstrated. This case has direct implications for how we formulate risk and explain mechanisms of violence.

Research examining U.S. case law on the PCL-R highlights how courts can shape, and sometimes distort, the role of assessment tools in violence risk opinions. Researchers found that the use of the PCL-R increased dramatically between 2005 and 2011, particularly in sexually violent person (SVP) and parole cases, and was introduced primarily by the prosecution. Challenges arise when evaluators describe its predictive value in ways that exceed the scientific literature, creating testimony that appears more certain or determinative than the data allow. Case law revealed systematic differences in how scores were reported by prosecution and defense experts, frequent pairing of the PCL-R with other risk instruments (raising concerns about double-counting risk), and a tendency to equate high scores with high future violence risk, despite the PCL-R not being a risk assessment tool per se.

SVP statutes and case law vary substantially across jurisdictions. As forensic psychologists specializing in violence risk assessment, we must understand the specific legal standards governing the cases we evaluate.

Jurisdictional variation (varying by state and court) affects:

• The definition of qualifying mental conditions
• The threshold for dangerousness
• The evidentiary weight given to actuarial versus SPJ tools
• The required nexus between diagnosis and future risk

An assessment that is legally sufficient in one jurisdiction may be inadequate in another. As forensic psychologists, we should tailor our evaluations to the legal framework in which they will be used, while maintaining scientific integrity.

A national review of Sexually Violent Person (SVP) statutes and related case law demonstrates how profoundly legal definitions and procedures shape the practice of violence risk assessment. Researchers found that although many SVP laws are modeled after constitutional benchmarks established in Kansas v. Hendricks, states vary widely in how they define key concepts such as “mental abnormality,” “likely to reoffend,” standards of proof, and procedural safeguards. Case law further reveals how these statutes are interpreted in practice, often filling gaps left by vague or incomplete legislative language.

For forensic psychologists, this variability has direct implications for assessment methodology, tool selection, risk communication, and testimony. Scientifically sound evaluations can still fail legally if they do not align with jurisdiction-specific statutory definitions, evidentiary standards, and due process requirements, underscoring the importance of legal literacy as an essential component of competent violence risk assessment in SVP contexts.

Recent litigation continues to test the constitutional boundaries and scope of expert opinions in violence risk assessment. Courts are increasingly attentive not only to whether risk exists, but to how risk is conceptualized, explained, and justified over time. This shift reflects growing concern that assessments relying too heavily on static or historical factors may fail to capture meaningful change, overstate dangerousness, or inadequately support continued deprivation of liberty.

Courts have expressed heightened scrutiny of evaluations that emphasize past violence without sufficient consideration of dynamic risk and protective factors, fail to articulate plausible pathways for risk reduction, or lack clear connections between assessment findings and available risk management options. These concerns signal an expectation that violence risk assessments move beyond categorical conclusions and instead demonstrate ongoing, individualized reasoning that remains responsive to change.

For forensic psychologists, these developments require refinement in both assessment practice and expert testimony. Risk opinions must increasingly integrate dynamic and protective factors, explain how risk may escalate or diminish over time, and explicitly link assessment findings to least-restrictive alternatives consistent with constitutional principles. This type of multifaceted evaluation includes demonstrating how treatment response, supervision conditions, environmental stability, and supports alter risk trajectories, rather than relying solely on static labels or historical severity.

Importantly, emerging case law reinforces that constitutionally defensible risk assessments are not merely accurate at a single point in time, but current, contextualized, and forward-looking in a manner that remains proportionate to the legal decision being made. Evaluations that fail to account for change or that present risk as fixed are increasingly vulnerable to challenge.

How Can I, As a Forensic Psychologist, Integrate Case Law Into Expert-Level Practice?

Integrating case law into forensic practice involves internalizing the principles courts apply when evaluating expert evidence and ensuring they are reflected in assessment reasoning and conclusions.

Expert-level practice is strengthened when forensic psychologists remain current with relevant appellate decisions, understand jurisdiction-specific statutory and evidentiary standards, and consult with legal professionals when appropriate. Most critically, legal constraints should be reflected in how risk is formulated, communicated, and bounded, ensuring that opinions remain scientifically grounded, professionally appropriate, and ethically sound.

When case law is meaningfully integrated into violence risk assessment, evaluations are better positioned to function effectively across clinical, institutional, and legal contexts—supporting public safety while respecting constitutional limits on state intervention.

As forensic psychologists specializing in violence risk assessment, we must recognize that case law is not peripheral to our work; instead, it defines the boundaries within which our opinions operate. Foundational SVP cases, jurisdictional variations, and emerging constitutional challenges shape what courts will accept as legitimate expert evidence. Understanding these legal constraints allows us to produce assessments that are scientifically sound, ethically responsible, and constitutionally defensible. It also enables us to communicate risk with clarity, restraint, and credibility.

In an era of heightened scrutiny of expert testimony, legal literacy is not an optional enhancement to violence risk assessment practice. It is a core component of expert-level forensic psychology.

Training

• Violence Risk Assessment Certificate
• AAFP: Case Law - Criminal Responsibility
• AAFP: Case Law Series: Competence to Stand Trial
• AAFP: Case Law Series: Juvenile Justice
• AAFP: Case Law: Disability & Worker's Compensation
• Legal Issues and Violence Risk
• MDLPA: Landmark Criminal Law and Procedure Cases Involving Persons with Mental Disabilities
• An Introduction to Violence Risk/Threat Assessment: Legal Issues

Blog Posts

• Rapid Growth of PCL-R Use in U.S. Courts Accounted for by Prosecution of Sexually Violent Predators and Parole Hearings
• Sexual Violence (RSVP-V2 & SVR-20-V2)
• Sexually Violent Person Statutes Differ Considerably Throughout the United States
• What are the Roles and Responsibilities of a Forensic Psychologist?
• Sexually Violent Predator Commitment – What We Know and What Works