Nicholas Scurich

University of California, Irvine | UCI ·  Department of Psychology and Social Behavior

Purpose Child Protective Services (CPS) investigates millions of cases of child maltreatment each year in the United States. A sizeable percentage of these cases involve allegations of sexual abuse. Little is known about the factors that are associated with cases being substantiated. Method The present manuscript analyzes data collected by the Nat...

This study examined how variations in signature complexity affected the ability of forensic document examiners (FDEs) and laypeople to determine whether signatures are authentic or simulated (forged), as well as whether they are disguised. Forty‐five FDEs from nine countries evaluated nine different signature comparisons in this online study. Recei...

Purpose This study aims to use a novel data set of 636 murderers sentenced to death in California to investigate homicide offenses that are committed but not prosecuted or officially solved, a concept known as the dark figure of crime. Design/methodology/approach Uaing appellate records from the Supreme Court of California, which contain extensive...

The modern canon of open science consists of five “schools of thought” that justify unfettered access to the fruits of scientific research: i) public engagement, ii) democratic right of access, iii) efficiency of knowledge gain, iv) shared technology, and v) better assessment of impact. Here, we introduce a sixth school: due process. Due process un...

The CPORT algorithm, commonly used to estimate the risk that a child pornography offender will offend again, hasn’t been validated for use in the U.S.

Signal detection theory posits that a rational decision made under uncertainty is a function of three properties: discriminability, base rates, and the relative cost of false positive and false negative errors, referred to in legal contexts as a Blackstone ratio. Building on the analysis by Smith and Wells (2024), which focuses on discriminability,...

When it comes to questions of fact in a legal context—particularly questions about measurement, association, and causality—courts should employ ordinary standards of applied science. Applied sciences generally develop along a path that proceeds from a basic scientific discovery about some natural process to the formation of a theory of how the proc...

Benefit–cost analyses are critical to support U.S. agencies’ programmatic decision making. These analyses are particularly challenging when one of the benefits is adversary deterrence. This paper presents a framework for calculating the value of deterrence related to countermeasures implemented to mitigate an attack by an adaptive adversary. We off...

Purpose Research on women who sexually abuse children is relatively scarce and tends to rely on small or unrepresentative convenience samples. The purpose of the current descriptive study is to examine characteristics female perpetrators of child sexual abuse using a large and contemporary dataset. Design/methodology/approach This study analyzes d...

Objectives: A sizeable percentage of federally-sentenced child pornography offenders have no history of other criminal offenses (hereinafter “child pornography-exclusive offenders”). There is a critical legal need to assess the recidivism risk of this population. The Child Pornography Risk Tool (CPORT) is a commonly-used actuarial risk assessment i...

The limited existing research on how jurors evaluate informant testimony suggests jurors may not be appropriately responsive to cues that could signal informant unreliability. In particular, jurors may fail to account for and properly weigh evidence that an informant is testifying for an incentive when reaching a verdict. However studies in this ar...

The field of psychology–law is extremely broad, encompassing a strikingly large range of topic areas in both applied psychology and experimental psychology. Despite the continued and rapid growth of the field, there is no current and comprehensive resource that provides coverage of the major topic areas in the psychology–law field. The Oxford Handb...

One question Professors Arkes and Koehler (2022) (hereinafter ‘A&K’) ask in their thoughtful paper is ‘What role should “inconclusives” play in the computation of error rates?’ (p. 5) The answer to this question is vital because the number of inconclusives in firearm error rate studies is staggering. For example, firearm examiners in the FBI/Ames L...

The matching of bullets to guns is subjective, and courts are starting to question it because of testimony from scientific experts

Purpose Official criminal justice statistics (e.g. arrest rates) underestimate the frequency of crime because not all crime gets reported to authorities, a phenomenon known as the “dark figure of crime.” The present study aims to examine the dark figure of violence committed by discharged psychiatric patients. Design/methodology/approach Multiple...

A sample (n = 79) of practicing firearm and toolmark examiners was queried about casework as well as their views about the potential role that statistics might play in future firearm examinations and expert witness testimony. Principal findings include: The modal response for time spent conducting bullet examinations is 2–4 h, and the modal respons...

Two studies using large samples of jury-eligible adults tested whether hindsight influences perceptions of potential grooming behaviours. In study 1, participants (n = 371) were presented with vignettes describing five different interactions between an adult and children and rated the likelihood that these behaviours were indicative of sexual abuse...

Polymorphic or crossover sexual offenders have victims in different categories (e.g., adult and child victims; male and female victims; related and non-related victims). The present study systematically reviewed and synthesized the existing literature in an effort to ascertain the prevalence of crossover among sexual offenders that takes into accou...

The New Mexico Supreme Court recently considered whether a trial court had erred in excluding behavioral genetic evidence of a murder defendant's low-activity monoamine oxidase A (MAOA) gene, which the defendant argued had predisposed him-along with his history of childhood maltreatment-to "maladaptive or violent behavior." After an extensive analy...

Objective: To assess the relative contributions of normative and informational influence in group decisions with a binary outcome. Method: We examined vote-switching behavior in the context of jury deliberation with a novel 2 × 2 experimental paradigm. Two-hundred and forty-one university students (median age = 20, 77% female, 12% South Asian, 15%...

Objectives: Firearms experts traditionally have testified that a weapon leaves "unique" toolmarks, so bullets or cartridge casings can be visually examined and conclusively matched to a particular firearm. Recently, due to scientific critiques, Department of Justice policy, and judges' rulings, firearms experts have tempered their conclusions. In...

*** THE FULL PAPER IS NOW FREELY & PUBLICALLY AVAILABLE AT: https://www.sciencedirect.com/science/article/pii/S2589871X20300553 ***ABSTRACT: Forensic science error rate studies have not given sufficient attention or weight to inconclusive evidence and inconclusive decisions. Inconclusive decisions can be correct decisions, but they can also be...

Objective: Use of risk assessment instruments in the criminal justice system is controversial. Advocates emphasize that risk assessments are more transparent, consistent, and accurate in predicting re-offending than judicial intuition. Skeptics worry that risk assessments will increase socioeconomic disparities in incarceration. Ultimately, judges...

Risk assessment algorithms are increasingly—and controversially—being used to inform whether criminal defendants are released or held in custody prior to their adjudications. A representative sample of Californians (n = 420)—the most recent state to consider eliminating cash bail and adopt an algorithmic approach to pretrial detention—was used to a...

Empirical studies of sexual offender recidivism have proliferated in recent decades. Virtually all of the studies define recidivism as a new legal charge or conviction for a sexual crime, and these studies tend to find recidivism rates of the order of 5–15% after 5 years and 10–25% after 10+ years. It is uncontroversial that such a definition of re...

The putative confession instruction (“[suspect] told me everything that happened and wants you to tell the truth”) during forensic interviews with children has been shown to increase the accuracy of children’s statements, but it is unclear whether adult’s perceptions are sensitive to this salutary effect. The present study examined how adults perce...

This article focuses on how judges present arguments in written opinions and whether the predominant style of argumentation promotes the legitimacy of the judiciary. Judicial opinions are habitually unequivocal, overstated, and lacking of any doubt that the singularly correct decision was reached. Studies examining the effect of argumentation in ju...

Risk estimates can be communicated in a variety of forms, including numeric and categorical formats. An example of the latter is “low/medium/high risk.” The categorical format is preferred by judges and practitioners alike, and is mandated by the most commonly utilized forensic risk assessment instruments (the HCR‐20 and the Static‐99). This articl...

Negative forensic evidence can be defined as the failure to find a trace after looking for it. Such evidence is often dismissed by referring to the aphorism "absence of evidence is not evidence of absence." However, this reasoning can be misleading in the context of forensic science. This commentary is designed to help forensic scientists understan...

Much legal discourse has focused on the probable cause standard and the constitutionality of law enforcement searches. Existing case law stipulates that probable cause requires less than 50% certainty in a suspect's involvement in a crime, and that it should be applied consistently regardless of the crime at hand or type of search in question. Beca...

The role of experts and their presentation of testimony in insanity cases remain controversial. In order to decrease possible expert bias associated with this testimony, a number of different alternatives to adversarial presentation have been suggested. Two such alternatives are the use of court‐appointed experts and the use of concurrent testimony...

Gruesome crime scene and autopsy photographs are admissible evidence under the Federal Rules of Evidence (FRE) if their probative value substantially outweighs their prejudicial impact. Despite important methodological differences and mixed results from past studies, recommendations from the psychological literature have been made about the prejudi...

Fingerprint examiners traditionally express conclusions in categorical terms, opining that impressions do or do not originate from the same source. Recently, probabilistic conclusions have been proposed, with examiners estimating the probability of a match between recovered and known prints. This study presented a nationally representative sample o...

Introduction of genetic evidence of a predisposition to violent or impulsive behaviour is on the rise in criminal trials. However, a panoply of data suggests that such evidence is ineffective at reducing judgements of culpability and punishment, and therefore its use in the legal process is likely to diminish.

Two experiments tested (a) whether jurors make assumptions about the potential punishment that would follow from a guilty verdict, (b) whether those assumptions influence jurors' implicit threshold for reasonable doubt, and (c) whether informing jurors of the potential punishment additionally influences their implicit threshold. Experiment 1 manipu...

Two jury simulation experiments tested participants’ sensitivity to variations in the probative value of a piece of negative forensic evidence: failure to find gunshot residue (GSR) on a defendant alleged to have fired a gun. Experiment 1 found that if no GSR was detected, juries (N = 115) of undergraduates were appropriately less likely to convict...

Referrals and admissions to state psychiatric hospitals of criminal defendants found Incompetent to Stand Trial (IST) are on the rise in the state of California and other parts of the country. Studies of treatment outcomes of this population have primarily focused on factors that determine competency and/or restorability. However, as IST patients p...

In order to identify victims of child neglect, social service workers rely heavily on referrals from concerned friends, neighbors, and others in the community. Little is known, however, about how lay individuals perceive child neglect and what factors influence their decision to make a referral. This study explored the effects of child, parent, and...

Criminal defendants found incompetent to stand trial (IST) are sent to state hospitals for treatment to be restored to competency. IST patients diagnosed with dementia and related disorders present a particular challenge to clinicians, because they must be restored successfully within a statutorily mandated time frame (e.g., 3 years in California f...

The United States Supreme Court recently abolished mandatory life in prison without parole (LWOP) for juvenile offenders, holding that the practice is inconsistent with the eighth amendment’s cruel and unusual punishment clause, and its “evolving standards of decency” jurisprudence. The Court explicitly left open the question of whether nonmandator...

The presumption of innocence explicitly forbids jurors from using official suspicion or indictment as evidence of guilt in a criminal trial. A behavioral experiment tested whether jurors follow this prescription. It revealed that, compared to when a suspect had been merely named, jurors thought that the individual was significantly more likely to b...

The state of public opinion regarding the death penalty has not experienced such flux since the late 1960s. Death sentences and executions have reached their lowest annual numbers since the early 1970s and today, the public appears fairly evenly split in its views on the death penalty. In this Essay, we explore, first, whether these changes in publ...

Although research reveals that children as young as 3 can use deception and will take steps to obscure truth, research concerning how well others detect children's deceptive efforts remains unclear. Yet adults regularly assess whether children are telling the truth in a variety of contexts, including at school, in the home, and in legal settings, p...

Rap music has had a contentious relationship with the legal system, including censorship, regulation, and artists being arrested for lewd and profane performances. More recently, rap lyrics have been introduced by prosecutors to establish guilt in criminal trials. Some fear this form of artistic expression will be inappropriately interpreted as lit...

The assessment of future dangerous behavior plays a central role in a variety of legal decisions. Instruments specifically designed to assess the risk of future dangerous behavior have proliferated and received myriad scholarly attention in the recent decades. By contrast, little is known empirically about the effect that such assessments have on l...

The current research investigated the mechanisms by which perceptions of confession evidence both influence and are influenced by perceptions of other case evidence using the theoretical framework of coherence-based reasoning (CBR). CBR posits that ambiguity and uncertainty are eschewed by artificially imposing consistency between pieces of evidenc...

In Stackelberg security games, a defender must allocate scarce resources to defend against a potential attacker. The optimal defense involves the randomization of scarce security resources, yet how attackers perceive the risk given randomized defense is not well understood. We conducted an experiment where attackers chose whether to attack or not a...

Links between genetic variants and negatively valenced behaviors have stimulated intense commentary about the implications for responsibility and punishment. Previous research has suggested that behavioral genetic evidence of a predisposition to negative behaviors has modest to no impact on mitigation of punishment, at least for serious crimes. Dat...

The presumption of innocence is sacrosanct in Anglo-legal doctrine, yet how jurors interpret it remains unknown. This experiment manipulated the alleged crime (violent, child, or sexual assault) and the defendant’s physical appearance (good, mediocre, or bad). Following Savage (1954), uncertainty about the guilt of the defendant was conceptualized...

The incarceration of criminal offenders in the United States has reached epidemic proportions. One way to scale back the prison population is by using empirical risk assessment methods to apportion prison sentences based on the likelihood of the offender recidivating, so-called "evidence-based sentencing." This practice has been denounced by some l...

Psychological assessment instruments designed to assist mental health experts in conducting forensic evaluations have proliferated in the past 2 decades. These instruments are intended to increase objectivity and reliability and therefore theoretically reduce bias. However, a burgeoning body of research suggests that when such instruments are appli...

Demonstrations of a link between genetic variants and criminal behavior have stimulated increasing use of genetic evidence to reduce perceptions of defendants' responsibility for criminal behavior and to mitigate punishment. However, because only limited data exist regarding the impact of such evidence on decision makers and the public at large, we...

How to communicate risk of recidivism in correctional and forensic contexts has been a subject of scholarly discussion for two decades. This emerging literature, however, is sparse compared with studies on the assessment of risk for violent and offending behavior. In this special issue of Behavioral Sciences and the Law, we have gathered together e...

Some claim that recent advances in neuroscience will revolutionize the way we think about human nature and legal culpability. Empirical support for this proposition is mixed. Two highly-cited empirical studies found that irrelevant neuroscientific explanations and neuroimages were highly persuasive to laypersons. However, attempts to replicate thes...

Contrary to popular belief, forensic science - including forensic DNA testing - is not infallible. The rate at which errors occur exerts an inordinate impact on the probative value of a DNA match. Previous research indicates that jurors are insensitive to this effect. The current study tests two possible explanations for the observed insensitivity:...

Twenty states, the District of Columbia, and the federal government allow for the postincarceration, indeterminate civil commitment of sexual violent predators (SVPs). Yet, although a large number of individuals has been committed under these laws, relatively little is known about how jurors make decisions in these proceedings. Using a sample of 27...

Twenty states, the District of Columbia, and the federal government allow for the postincarceration, indeterminate civil commitment of sexual violent predators (SVPs). Yet, although a large number of individuals has been committed under these laws, relatively little is known about how jurors make decisions in these proceedings. Using a sample of 27...

Recent advances in behavioral genetics suggest a modest relationship among certain gene variants, early childhood experiences, and criminal behavior. Although scientific research examining this link is still at an early stage, genetic data are already being introduced in criminal trials. However, the extent to which such evidence is likely to affec...

The public's view of the judiciary is a key factor in the legitimacy of any legal system. Ideally, popular judgments of the adjudicative branch would be independent of the outcomes of the decisions it furnishes. In a previous study (Simon & Scurich 2011), we found that lay people's evaluations of the judicial decision-making process were highly con...

Security of infrastructure is a major concern. Traditional security schedules are unable to provide omnipresent coverage; consequently, adversaries can exploit predictable vulnerabilities to their advantage. Randomized security schedules, which randomly deploy security measures, overcome these limitations, but public perceptions of such schedules h...

Forensic science is not infallible, as data collected by the Innocence Project have revealed. The rate at which errors occur in forensic DNA testing-the so-called "gold standard" of forensic science-is not currently known. This article presents a Bayesian analysis to demonstrate the profound impact that error rates have on the probative value of a...

Risk assessment expert testimony remains an area of considerable concern within the U.S. legal system. Historically, controversy has surrounded the constitutionality of such testimony, while more recently, following the adoption of new evidentiary standards that focus on scientific validity, the admissibility of expert testimony has received greate...

Thousands of children testify each year in the United States (Ceci & de Bruyn, 1999). Children testify both as witnesses and victims in a variety of legal settings, including family court, dependency court, civil matters, and, most conspicuously, in criminal cases in which sexual abuse is alleged (Quas & Sumaroka, 2012). In many of these cases, muc...

The public’s view of the judiciary is a key factor in the legitimacy of any legal system. Ideally, popular judgments of the adjudicative branch would be independent of the decisions. In a previous study (Simon & Scurich, 2011), we found that lay people’s evaluations of the judicial decision-making process were highly contingent on the outcome of th...

The doctrine of reasonable doubt is deeply entrenched within American culture, but the concept continues to mystify legal scholars, courts and jurors, and a coherent definition remains elusive. Reasonable doubt (RD) can be reified with the tool of decision theory as a tradeoff between acquitting the guilty and convicting the innocent. For instance,...

Structured methods to assess violence risk have proliferated in recent years, but such methods are not uncontroversial. A "core controversy" concerns the extent to which an actuarial risk estimate derived at the group level should-morally, logically, or mathematically-apply to any particular individual within the group. This study examines the rela...

We describe a Bayesian approach to evaluating children's abuse disclosures and review research demonstrating that children's disclosure of genital touch can be highly probative of sexual abuse, with the probative value depending on disclosure spontaneity and children's age. We discuss how some commentators understate the probative value of children...

In child sexual abuse cases, the victim's testimony is essential, because the victim and the perpetrator tend to be the only eyewitnesses to the crime. A potentially important component of an abuse report is the child's subjective reactions to the abuse. Attorneys may ask suggestive questions or avoid questioning children about their reactions, ass...

This study examined laypeople's evaluations of judicial decision making, specifically of the judicial decision-making process and the judiciary's legitimacy. Seven-hundred participants were presented with three judicial decisions, which were portrayed as following on the heels of solid and appropriate legal procedure. Each decision was accompanied...

Genetic databases are highly controversial. Significant controversy followed a report by the National Research Council (1996) concluding that a DNA match resulting from a database trawl is less probative than when only a single test is conducted. Legal scholars and statisticians have demonstrated why this conclusion is specious, but there is no emp...

The logical import of base rates is known among violence risk assessment researchers, but there has been little epistemological discussion of base rates, including identification of the relevant base rate and determining from whence the relevant base rate ought to come. This article describes the substantive considerations before examining whether...

Mechanical restraints are highly controversial because of the seriousness of their consequences. Death and severe physical and psychological injury are not uncommon consequences, yet, at the same time, restraints can be used to effectively avert violence and prevent injury. Hence, advocates call for their abolition and professionals regard them as...

In a previous study (presented at CELS 2009; in press, JELS), we tested how lay people evaluate judicial decision-making. Participants were presented with three judicial decisions, and were asked to evaluate the acceptability of those decisions, focusing on the decision-making process and on the courts’ legitimacy. One of the central findings of th...

Recent attempts to indict the use of actuarial risk assessment instruments have relied on confidence intervals to demonstrate that risk estimates derived at the group level do not necessarily apply to any specific individual within that group. This article contends that frequentist confidence intervals are inapposite to the current debate. Instead,...

Despite a proliferation of actuarial risk assessment instruments, empirical research on the communication of violence risk is scant and there is virtually no research on the consumption of actuarial risk assessment. Using a 2 × 3 Latin Square factorial design, this experiment tested whether decision-makers are sensitive to varying levels of risk ex...

There is an ethical debate about whether mental health professionals should predict dangerousness. One powerful objection involves considering the nature and scope of what is being predicted. Dangerousness is a bifurcated concept with a descriptive component, corresponding to risk factors and their relation to violence, and a normative component, c...

In child sexual abuse cases, the victim’s testimony is essential, because the victim and the perpetrator tend to be the only eyewitnesses to the crime. Children exhibit little affect when describing abuse, but jurors expect emotional displays when evaluating credibility. Attorneys may ask suggestive questions or avoid questioning children about the...