Evidence and Proof in Law

Abstract. Suppose that the word of an eyewitness makes it 80% probable that A committed a crime, and that B is drawn from a population in which the incidence rate of that crime is 80%. Many philosophers and legal theorists have held that if this is our only evidence against those parties then (i) we may be justified in finding against A but not against B; but (ii) that doing so incurs a loss in the accuracy of our findings. This (...) paper argues against (ii). It argues that accuracy considerations can motivate taking different attitudes towards individualized and statistical evidence even across cases where they generate the same probability that the defendant is guilty. (shrink)

Purpose: Illicit financial flows are targeted by the United Nations’ (UN) Sustainable Development Goals (SDGs). However, these illicit flows are not entirely understood. Furthermore, they can benefit from economic norms, laws, and regulations that lack mechanisms to detect and penalize them. This paper investigates whether a recent test, the embezzler test, can be used to identify regulatory architectures that facilitate illicit financial flows and related financial crimes. -/- Design/methodology/approach: To develop a more advanced version of the embezzler test in terms (...) of definitions and practical implementation methodology. -/- Findings: In this test, the definition of embezzlement can be understood to be the occurrence of illicit financial flows crossing the boundaries of organizations and/or countries. This is a multi-stage test, which intentionally simulates illicit financial flows to observe how well equipped is the regulatory architecture to deal with other financial offences that are related with these flows, such as theft, money laundering, fraud, corruption, market manipulation, and tax evasion. -/- Originality: This is the first explicit test that has been presented to identify norms, laws, and regulations that facilitate illicit financial flows and related financial crimes. -/- Research implications: Future research can employ the version of this test to stress test a large range of economic norms, laws, and regulations. -/- Practical/Social implications: This test’s new version can assist achieve the UN SDGs’ illicit financial flow reduction target. Furthermore, it can be used to study both existing and proposed norms, laws, and regulation. (shrink)

Criminal juries make decisions of great importance. A key criticism of juries is that they are unreliable in a multitude of ways, from exhibiting racial or gendered biases, to misunderstanding their role, to engaging in impropriety such as internet research. Recently, some have even claimed that the use of juries creates injustice on a large-scale, as a cause of low conviction rates for sexual criminality. Unfortunately, empirical research into jury deliberation is undermined by the fact that researchers are unable to (...) study live juries. The indirect sources of evidence used by researchers suffer from various problems, the most important of which is dubious levels of ecological validity. Real jury research—studying live jury deliberation—is controversial. However, as I argue, the objections to it are unconvincing. There is in fact a moral imperative to facilitate real jury research. (shrink)

Jury science is fraught with difficulty. Since legal and institutional hurdles render it all but impossible to study live criminal jury deliberation, researchers make use of various indirect methods to evaluate jury performance. But each of these methods are open to methodological criticism and, strikingly, some of the highest-profile jury research programmes in recent years have reached opposing conclusions. Uncertainty about jury performance is an obstacle for legal reform—ongoing debates about the ‘justice gap’ for complainants of sexual offences has rendered (...) these problems stark. This paper proposes a way to advance the debate. (shrink)

This paper defends an analysis of the epistemic contours of the interface between individuals and their cultural milieu.

La literatura sobre razonamiento probatorio busca incidir en la determinación de los hechos en los procesos judiciales. Para alcanzar dicho propósito, no basta con dirigir la mirada hacia disciplinas extrajurídicas exitosas e integrar lo que de ellas pueda extraerse a las teorías jurídicas de la prueba y a la práctica judicial. Es necesario, además, considerar el tipo de hechos a probar, los roles de las reglas jurídicas aplicables, y asumir que litigantes y jueces, actuando en un contexto institucional, podrán ser (...) más o menos agudos en la discusión fáctica, entre otras cosas. Minimizar la influencia de tales factores expone a los estudios probatorios a tener un bajo rendimiento práctico. Algo de esto ha ocurrido con la llamada concepción racionalista de la prueba. Su innegable aporte al debate académico en español no ha ido a la par de su impacto judicial. Para explicar esta brecha entre teoría y práctica, identificamos tres creencias-obstáculo que afectan a su discurso sobre la prueba y que deben ser sorteadas si lo que se busca es influir en la forma en que se juzgan los hechos en un sistema judicial realmente existente. (shrink)

“Excited Delirium Syndrome” (ExDS) is a controversial diagnosis. The supposed syndrome is sometimes considered to be a potential cause of death. However, it has been argued that its sole purpose is to cover up excessive police violence because it is mainly used to explain deaths of individuals in custody. In this paper, we examine the epistemic conditions giving rise to the controversial diagnosis by discussing the relation between causal hypotheses, evidence, and data in forensic medicine. We argue that the practitioners’ (...) social context affects causal inquiry through background assumptions that enter inquiry at multiple stages. This analysis serves to better understand the wide usage of the controversial diagnosis of ExDS. (shrink)

This essay is an accessible introduction to the proof paradox in legal epistemology. -/- In 1902 the Supreme Judicial Court of Maine filed an influential legal verdict. The judge claimed that in order to find a defendant culpable, the plaintiff “must adduce evidence other than a majority of chances”. The judge thereby claimed that bare statistical evidence does not suffice for legal proof. -/- In this essay I first motivate the claim that bare statistical evidence does not suffice for legal (...) proof. I then introduce and motivate a knowledge-centred explanation of this fact. The knowledge-centred explanation rests on two premises. The first is that legal proof requires knowledge of culpability. The second is that one cannot attain knowledge that p from bare statistical evidence that p. To motivate the second premise, I suggest that beliefs based on bare statistical evidence fail to be safe—they could easily be wrong—and bare statistical evidence cannot eliminate relevant alternatives. -/- I then cast doubt on the first premise; I argue that legal proof does not require knowledge. I thereby dispute the knowledge-centred explanation of the inadequacy of bare statistical evidence for legal proof. Instead of appealing to the nature of knowledge, I suggest we should seek a more direct explanation by appealing to those more foundational epistemic properties, such as safety or eliminating relevant alternatives. (shrink)

I defend the thesis that legal standards of proof are reducible to thresholds of probability. Many reject this thesis because it appears to permit finding defendants liable solely on the basis of statistical evidence. To the contrary, I argue – by combining Thomson's (1986) causal analysis of legal evidence with formal methods of causal inference – that legal standards of proof can be reduced to probabilities, but that deriving these probabilities involves more than just statistics.

The proof paradox results from conflicting intuitions concerning different types of fallible evidence in a court of law. We accept fallible individual evidence but reject fallible statistical evidence even when the conditional probability that the defendant is guilty given the evidence is the same, a seeming inconsistency. This paper defends a solution to the proof paradox, building on a sensitivity account of checking and settling a question. The proposed sensitivity account of legal proof not only requires sensitivity simpliciter but sensitivity (...) of each relevant step of the proof procedure and/or sensitivity concerning all relevant alternatives. This account avoids problems that have been identified for other sensitivity views of legal proof. Moreover, it is argued that sensitivity, rather than safety, is the crucial modal condition for legal proof. It is, finally, shown that the provided account can fruitfully support very different existing views on the relationship between knowledge and legal proof. (shrink)

Discusses the question of whether trials should just use two verdicts (e.g. guilty or not guilty) or whether they use multiple verdicts.

An introduction to philosophical research on the standards of legal proof.

Discusses whether legal proof is merely probabilistic, focusing on the famous proof paradox.

Discusses the idea that legal proof should use variable standards rather than a single fixed threshold.

Criminal courts make decisions that can remove the liberty and even life of those accused. Civil trials can cause the bankruptcy of companies employing thousands of people, asylum seekers being deported, or children being placed into state care. Selecting the right standards when deciding legal cases is of utmost importance in giving those affected a fair deal. This Element is an introduction to the philosophy of legal proof. It is organised around five questions. First, it introduces the standards of proof (...) and considers what justifies them. Second, it discusses whether we should use different standards in different cases. Third, it asks whether trials should end only in binary outcomes (e.g. guilty or not guilty) or rather use more fine-grained or precise verdicts. Fourth, it considers whether proof is simply about probability, concentrating on the famous 'Proof Paradox'. Finally, it examines who should be trusted with deciding trials, focusing on the jury system. (shrink)

Discusses who should decide the result of legal trials, focusing on the jury system.

In this paper I explore some ideas inspired by Federico Picinali’s Justice In-Between: A Study of Intermediate Criminal Verdicts. Picinali makes a case for the introduction of intermediate options in criminal trials – verdicts with consequences that are harsher than an acquittal, but not so harsh as a conviction. From a certain perspective, the absence of intermediate options in criminal trials is puzzling – out of kilter with much of our everyday decision-making and, perhaps, with the recommendations of expected utility (...) theory. I will argue, however, that the lack of intermediate options is much less puzzling when put in the context of our ordinary practices of blame and non-legal punishment. (shrink)

As artificial intelligence becomes more sophisticated and robots approach autonomous decision-making, debates about how to assign moral responsibility have gained importance, urgency, and sophistication. Answering Stenseke’s (2022a) call for scaffolds that can help us classify views and commitments, we think the current debate space can be represented hierarchically, as answers to key questions. We use the resulting taxonomy of five stances to differentiate—and defend—what is known as the “blank check” proposal. According to this proposal, a person activating a robot could (...) willingly make themselves answerable for whatever events ensue, even if those events stem from the robot’s autonomous decision(s). This blank check solution was originally proposed in the context of automated warfare (Champagne & Tonkens, 2015), but we extend it to cover all robots. We argue that, because moral answerability in the blank check is accepted voluntarily and before bad outcomes are known, it proves superior to alternative ways of assigning blame. We end by highlighting how, in addition to being just, this self-initiated and prospective moral answerability for robot harm provides deterrence that the four other stances cannot match. (shrink)

In epistemology, the concept of knowledge is of distinctive interest. This fact is also reflected in the discussion of epistemic value, which focuses to a large extend on the value problem of knowledge. This discussion suggests that knowledge has an outstanding value among epistemic standings because its value exceeds the value of its constitutive parts. I will argue that the value of knowledge is not outstanding by presenting epistemic standings of checking, transferring knowledge, and proving in court, whose values exceed (...) the value of knowledge in certain contexts. Moreover, the values of these other epistemic standings do not always rely on the value of knowledge. In terms of value, knowledge is not an outstanding epistemic concept. Hence, in terms of value we cannot find support for the privileged position that knowledge enjoys in epistemology. (shrink)

Resumen: Una de las formas más comunes y menos estudiadas de parcialidad judicial subjetiva es la disminución de la credibilidad otorgada a un testigo debido a un prejuicio identitario implícito del agente judicial. En la epistemología social, este fenómeno ha sido estudiado bajo la rúbrica de la injusticia testimonial. En este ensayo mostramos que para determinar la ocurrencia de un caso de injusticia testimonial en el derecho se deben cumplir tres condiciones que son imposibles de verificar empíricamente y que están (...) basadas en presupuestos psicológicos que han sido puestos en duda en años recientes. Sin la posibilidad de verificar estas condiciones, estamos frente a un tipo de parcialidad judicial indetectable. En su lugar, ofrecemos una nueva forma de entender la injusticia testimonial en el derecho como un fenómeno más general que describe una tendencia comportamental prejuiciosa recurrente por parte de un agente judicial. Entendida de este modo, la injusticia testimonial es completamente verificable. -/- Abstract: One of the most common and least studied forms of subjective judicial partiality is the credibility deficit suffered by a witness due to an implicit identity prejudice in a judicial agent. Social epistemologists have studied this form of partiality under the rubric, “testimonial injustice.” In this essay we argue that to verify the occurrence of a singular instance of testimonial injustice in law three facts must be established, none of which can be established with any degree of confidence. Furthermore, all of them are based on psychological suppositions that have been recently discredited. Without the possibility of establishing these facts, we end up with an undetectable form of subjective judicial partiality. In its place, we offer a new way of understanding testimonial injustice in law as a general phenomenon that describes a recurrent pattern of prejudiced behavior in a judicial agent. Under this characterization, testimonial injustice becomes empirically verifiable. (shrink)

Cada día es más evidente que existen muchas formas sutiles de exclusión y parcialidad que afectan el correcto funcionamiento de los sistemas jurídicos. El concepto de injusticia epistémica, introducido por la filósofa Miranda Fricker, ofrece una herramienta conceptual útil para comprender estas formas de exclusión y parcialidad judicial que a menudo pasan desapercibidas. En este artículo presentamos la teoría original de Fricker y algunas de las aplicaciones del concepto de injusticia epistémica en los procesos jurídicos. En particular, queremos demostrar que (...) la semilla sembrada por Fricker ha generado un floreciente campo de estudio en el cual el concepto se utiliza para analizar muchos fenómenos diferentes en el ámbito jurídico, no siempre siguiendo la caracterización original proporcionada por ella. Esto ha llevado a una distinción entre lo que llamaremos la versión estrecha del concepto, que se acerca a la descripción original de Fricker, y la versión más amplia de injusticia epistémica, que es una noción más controvertida porque existe el riesgo de que se confunda con otros conceptos más conocidos como el sexismo, la discriminación racial, la opresión, el silenciamiento y el gaslighting. Mostraremos que el valor de la versión estrecha es principalmente teórico y que para utilizar el concepto de injusticia epistémica se debe adoptar una comprensión más liberal del mismo. (shrink)

There is a growing awareness that there are many subtle forms of exclusion and partiality that affect the correct workings of a judicial system. The concept of epistemic injustice, introduced by the philosopher Miranda Fricker, is a useful conceptual tool to understand forms of judicial partiality that often go undetected. In this paper, we present Fricker’s original theory and some of the applications of the concept of epistemic injustice in legal processes. In particular, we want to show that the seed (...) planted by Fricker has flourished into a rich field of study in which the concept is used to analyze many different phenomena in law, not always following the original characterization provided by her. This has led to a distinction between what we will call the narrow version of the concept, which is closer to Fricker’s original account, and the wider version of epistemic injustice, which is a more controversial notion because it is always on the verge of morphing into other well-known concepts like sexism, racial discrimination, oppression, silencing, and gaslighting. We will show that the value of the narrow version is mostly theoretical, and that in order to use the concept of epistemic injustice one must adopt a more liberal understanding of it. (shrink)

Should we use the same standard of proof to adjudicate guilt for murder and petty theft? Why not tailor the standard of proof to the crime? These relatively neglected questions cut to the heart of central issues in the philosophy of law. This paper scrutinises whether we ought to use the same standard for all criminal cases, in contrast with a flexible approach that uses different standards for different crimes. I reject consequentialist arguments for a radically flexible standard of proof, (...) instead defending a modestly flexible approach on non-consequentialist grounds. The system I defend is one on which we should impose a higher standard of proof for crimes that attract more severe punishments. This proposal, although apparently revisionary, accords with a plausible theory concerning the epistemology of legal judgments and the role they play in society. (shrink)

Should we use the same standard of proof to adjudicate guilt for murder and petty theft? Why not tailor the standard of proof to the crime? These relatively neglected questions cut to the heart of central issues in the philosophy of law. This paper scrutinises whether we ought to use the same standard for all criminal cases, in contrast with a flexible approach that uses different standards for different crimes. I reject consequentialist arguments for a radically flexible standard of proof, (...) instead defending a modestly flexible approach on non-consequentialist grounds. The system I defend is one on which we should impose a higher standard of proof for crimes that attract more severe punishments. This proposal, although apparently revisionary, accords with a plausible theory concerning the epistemology of legal judgments and the role they play in society. (shrink)

Researchers face perennial difficulties in studying live jury deliberation. As a result, the academic community struggles to reach a consensus on key matters of legal reform concerning jury trials. The hurdles faced by empirical jury researchers are often legal or institutional. This note argues that the legal and institutional barriers preventing live deliberation research should be removed and discusses two forms that live deliberation research could take.

Sentencing outcomes turn on moral and evaluative determinations. For example, a finding of “irreparable corruption” is generally a precondition for juvenile life without parole. A finding that the “aggravating factors outweigh the mitigating factors” determines whether a defendant receives the death penalty. Should such moral determinations that expose defendants to extraordinary penalties be subject to a standard of proof? A broad range of federal and state courts have purported to decide this issue “in the abstract and without reference to our (...) sentencing case law,” as the Supreme Court recently put it. Kansas v. Carr, 577 U.S. 108, 119 (2016). According to these courts, “it would mean nothing” to ask whether the defendant “deserves mercy beyond a reasonable doubt” or “more-likely-than-not deserves it” because moral questions are not “factual.” Instead, moral determinations are highly subjective “value calls” to which concepts of doubt and certainty do not intelligibly apply. -/- Implicit in these rulings is a controversial view of the nature of moral judgment. This Article traces the contours of the view and argues that it is out of step with the way the broader public thinks about morality and fails to address the issues defendants have raised. Courts should avoid wading into such controversial waters for two reasons. First, the judiciary has historically maintained neutrality on issues of significant public concern. Second, even if moral determinations are not factual, applying a standard of proof to at least some moral decisions at sentencing would change the outcome of the sentencer’s deliberations, and improve the legitimacy of the legal system. For the reasonableness of doubt depends on context; and moral questions—"are you certain the defendant deserves death?”—make salient the stakes relative to which a person should decide what to believe about ordinary empirical matters. On the resulting view, reasonable doubt in the final moral analysis is not just intelligible, but essential for correcting a bias in the structure of the bifurcated criminal trial that systematically disadvantages defendants: the tendency for de-contextualized "factual findings” in the guilt phase to control outcomes at sentencing. (shrink)

Law-enforcement agencies are increasingly able to leverage crime statistics to make risk predictions for particular individuals, employing a form of inference that some condemn as violating the right to be “treated as an individual.” I suggest that the right encodes agents’ entitlement to a fair distribution of the burdens and benefits of the rule of law. Rather than precluding statistical prediction, it requires that citizens be able to anticipate which variables will be used as predictors and act intentionally to avoid (...) them. Furthermore, it condemns reliance on various indexes of distributive injustice, or unchosen properties, as evidence of law-breaking. (shrink)

The article reviews on the technical attributes on current technologies deployed in outer space and those that are being developed and mass produced. The article refutes the Chinese state-controlled Xinhua News’ propaganda several years ago on objecting America’s deployment of nuclear technologies in outer space with rigorous scientific evidence. Furthermore, the article warns on the dangers of physical signals applied in outer space technologies that can threaten the solar system, especially the Mozi quantum satellite with photon beams. The article concludes (...) with the illicit practices by the Chinese state party with militant ambitions in the supposedly scientific institutions. It violates the spirit on the peaceful use of outer space, and goes against the 2222 (XXI) resolution adopted by the general assembly, including the 1967 Outer Space Treaty banning the stationing of weapons of mass destruction in outer space. (shrink)

Upon Brexit & Trade War, the research took a supply-side analysis in macroeconomic paradigm for the purpose and cause of the actions. In the geopolitical competitions on crude oil resources between the allied powers & the Russian hegemony, the latter of which has effective control over P. R. China’s multilateral behaviors, the external research induced that trade war, either by complete information in intelligence or an unintended result, was a supply chain attack in prohibiting the antisatellite weapon supplies in the (...) Northern regions of mainland China in relation to Russia. Although no substantive change to international relations, the Trade War’s prohibitive effect on the high frequency trading in the monetary domain of CNY was observed, which had been the source of economic bubbles in the import-export control regime with centralized banking. The paper argues that by realism in economy & military strategy, trade war was ineffective in deterring the covert operations of the People’s Liberation Army by their territorial strategies and raises questions in humanitarianism in conflict situations. Moreover, with gross privacy breaches by mass surveillance in domain politics, totalitarianism with coercions, and counterfeit of drone strikes, traditional methods of threat elimination are rendered less pragmatic apart from the adversaries’ cyber security breaches. With the scientific approach, I offer an ecological paradigm with historic analysis of the Chinese military’s conducts in terms economics. The territorial methods of the PLA are contextualized into the ecological paradigm in regionalism & public administration. Electronic combats of the Chinese regime with the Great Firewall and Denial-of-Service attacks not only contribute to the diminishing natural freedoms of the population, but also transgress the fundamental right to health along with non-traditional nuclear threats to P.R.C. itself. (shrink)

Esta breve introducción a la filosofía de la ciencia parte del hecho de que tanto la investigación científica como el razonamiento probatorio judicial tienen un carácter inductivo. En esa medida, comparten características esenciales que permiten que el derecho se nutra de muchas de las reflexiones de la filosofía de la ciencia. El capítulo se concentra en cuatro temas principales: los criterios de demarcación entre el conocimiento científico y la pseudociencia; el carácter derrotable de las conclusiones de la ciencia y el (...) derecho; la estructura corroborativa de la relación entre la evidencia y las hipótesis científicas y judiciales; y las teorías de la explicación tanto en el ámbito científico como en el judicial. (shrink)

Legal epistemology has been an area of great philosophical growth since the turn of the century. But recently, a number of philosophers have argued the entire project is misguided, claiming that it relies on an illicit transposition of the norms of individual epistemology to the legal arena. This paper uses these objections as a foil to consider the foundations of legal epistemology, particularly as it applies to the criminal law. The aim is to clarify the fundamental commitments of legal epistemology (...) and suggest a way to vindicate it. (shrink)

A gunman intends to shoot and kill Victim. He shoots and misses his target, but the gunshot startles a group of water buffalo, causing them to trample the victim to death. The gunman brings about the intended effect, Victim’s death, but in a “deviant” way rather than the one planned. This paper argues that such causal structures, deviant causal chains, pose serious problems for several key legal concepts. -/- I show that deviant causal chains pose problems for the legal distinction (...) between attempts and completed crimes, and also for the distinction between attempts and mere preparations. I then suggest that cases of deviant causation undermine notions of legal liability for completed crimes in terms of actus reus and mens rea, and argue that natural accounts of negligence misclassify some cases involving deviant causal chains. After diagnosing several conceptual vulnerabilities in the law revealed by deviant causal chains, I show that natural strategies for shoring up legal theories in the face of these examples are unpromising. (shrink)

In some cases, there appears to be an asymmetry in the evidential value of statistical and more individualized evidence. For example, while I may accept that Alex is guilty based on eyewitness testimony that is 80% likely to be accurate, it does not seem permissible to do so based on the fact that 80% of a group that Alex is a member of are guilty. In this paper I suggest that rather than reflecting a deep defect in statistical evidence, this (...) asymmetry might arise from a general constraint on rational inquiry. Plausibly the degree of evidential support needed to justify taking a proposition to be true depends on the stakes of error. While relying on statistical evidence plausibly raises the stakes by introducing new kinds of risk to members of the reference class, paradigmatically `individualized' evidence---evidence tracing back to A's voluntary behavior---can lower the stakes. The net result explains the apparent evidential asymmetry without positing a deep difference in the brute justificatory power of different types of evidence. (shrink)

Studying evidence law as part of naturalized epistemology means using the tools and results of the sciences to evaluate evidence rules based on the accuracy of the verdicts they are likely to produce. In this chapter, we introduce the approach and address skeptical concerns about the value of systematic empirical research for evidence scholarship, focusing, in particular, on worries about the external validity of jury simulation studies. Finally, turning to applications, we consider possible reforms regarding eyewitness identifications and character evidence.

Many philosophers have pointed out that statistical evidence, or at least some forms of it, lack desirable epistemic or non-epistemic properties, and that this should make us wary of litigations in which the case against the defendant rests in whole or in part on statistical evidence. Others have responded that such broad reservations about statistical evidence are overly restrictive since appellate courts have expressed nuanced views about statistical evidence. In an effort to clarify and reconcile, I put forward an interpretive (...) analysis of why statistical evidence should raise concerns in some cases but not others. I argue that when there is a mismatch between the specificity of the evidence and the expected specificity of the accusation, statistical evidence—as any other kind of evidence—should be considered insufficient to sustain a conviction. I rely on different stylized court cases to illustrate the explanatory power of this analysis. (shrink)

Philosophical Issues, Volume 31, Issue 1, Page 85-103, October 2021.

Why can testimony alone be enough for findings of liability? Why statistical evidence alone can’t? These questions underpin the “Proof Paradox” (Redmayne 2008, Enoch et al. 2012). Many epistemologists have attempted to explain this paradox from a purely epistemic perspective. I call it the “Epistemic Project”. In this paper, I take a step back from this recent trend. Stemming from considerations about the nature and role of standards of proof, I define three requirements that any successful account in line with (...) the Epistemic Project should meet. I then consider three recent epistemic accounts on which the standard is met when the evidence rules out modal risk (Pritchard 2018), normic risk (Ebert et al. 2020), or relevant alternatives (Gardiner 2019 2020). I argue that none of these accounts meets all the requirements. Finally, I offer reasons to be pessimistic about the prospects of having a successful epistemic explanation of the paradox. I suggest the discussion on the proof paradox would benefit from undergoing a ‘value-turn’. (shrink)

Predictive algorithms are playing an increasingly prominent role in society, being used to predict recidivism, loan repayment, job performance, and so on. With this increasing influence has come an increasing concern with the ways in which they might be unfair or biased against individuals in virtue of their race, gender, or, more generally, their group membership. Many purported criteria of algorithmic fairness concern statistical relationships between the algorithm’s predictions and the actual outcomes, for instance requiring that the rate of false (...) positives be equal across the relevant groups. We might seek to ensure that algorithms satisfy all of these purported fairness criteria. But a series of impossibility results shows that this is impossible, unless base rates are equal across the relevant groups. What are we to make of these pessimistic results? I argue that none of the purported criteria, except for a calibration criterion, are necessary conditions for fairness, on the grounds that they can all be simultaneously violated by a manifestly fair and uniquely optimal predictive algorithm, even when base rates are equal. I conclude with some general reflections on algorithmic fairness. (shrink)

In recent years, the concept of “integrity” has been frequently discussed by scholars, and deployed by courts, in the domain of criminal procedure. In this paper, we are particularly concerned with how the concept has been employed in relation to the problem of the admissibility of evidence obtained improperly. In conceptualising and addressing this problem, the advocates of integrity rely on it as a standard of conduct for the criminal justice authorities and as a necessary condition for the state authority (...) to condemn and punish. We raise a series of challenges that need answering before integrity can perform these roles. Our aim is not to show that integrity is useless in normative theorising about the admissibility of evidence, and about the criminal process in general. Rather, it is to give guidance for the elaboration of a theory of integrity that is cogent, coherent, and has useful implications for the process of proof. (shrink)

While many of us would not want to abandon the requirement that a defendant can only be found guilty of a serious criminal offence by a unanimous jury, we should not expect epistemology to give us the resources we need for justifying this requirement. The doubts that might prevent jurors from reaching unanimity do not show that, say, the BARD standard has not been met. Even if it were true, as some have suggested, that rationality requires that a jury composed (...) of epistemic peers should coalesce around one view about the defendant’s guilt, the failure to reach unanimity might be a good reason to worry about the epistemic failings of some small number of jurors but no reason to worry that we’ve failed to protect the defendant from an unjustified imposition of, say, the risk against wrongful conviction. The arguments for the unanimity requirement will need to come from outside of epistemology. (shrink)

Abstract: When do we meet the standard of proof in a criminal trial? Some have argued that it is when the guilt of the defendant is sufficiently probable on the evidence. Some have argued that it is a matter of normic support. While the first view provides us with a nice account of how we ought to manage risk, the second explains why we shouldn’t convict on the basis of naked statistical evidence alone. Unfortunately, this second view doesn’t help us (...) understand how we should manage risk (e.g., the risk of violating rights against wrongful conviction) and faces counterexamples of its own. I shall defend an alternative approach that builds on the strengths of these two accounts. On the approach defending here, it is objectively suitable to punish iff we know a defendant to be guilty. To determine what is consistent with procedural justice and to determine what we prospectively ought to do, we need to think about the risks we face of deviating from this objective ideal. (shrink)

Los sesgos cognitivos afectan negativamente la toma de decisiones en todas las esferas de la vida, incluyendo las decisiones de los jueces. La imposibilidad de eliminarlos por completo de la práctica del derecho, o incluso de controlar sus efectos, contrasta con el anhelo de que las decisiones judiciales sean el resultado exclusivo de un razonamiento lógico-jurídico correcto. Frente el efecto sistemático, recalcitrante y porfiado de los sesgos cognitivos, una posible estrategia para disminuir su efecto es enfocarse, no en modificar el (...) comportamiento de los agentes judiciales, sino en moldear su entorno para que los sesgos tengan menos oportunidades de aparecer. En particular, es más provechoso concentrar los esfuerzos en identificar aquellas reglas procesales que faciliten o limiten el efecto de los sesgos. En este ensayo propongo un diálogo fructífero entre el derecho y la psicología que puede llevar a mejorar la calidad de los sistemas judiciales. La propuesta está basada en la creación de guías de práctica judicial que puedan servir de base para la creación de protocolos procesales que limiten en la medida de lo razonable sus efectos negativos y conduzcan a mejores decisiones judiciales. (shrink)

Rules 405(a) and 608(a) of the Federal Rules of Evidence allow the use of testimony about a witness’s reputation to support or undermine his or her credibility in trial. This paper analyzes the evidential weight of such testimony from the point of view of social epistemology and the theory of social networks. Together they provide the necessary elements to analyze how reputation is understood in this case, and to assess the epistemic foundation of a reputational attribution. The result of the (...) analysis will be that reputational testimony is extremely weak from an epistemological point of view, and that in many cases there are more reliable substitutes that achieve a similar purpose. The obvious fix, in my view, is to eliminate the use of reputation testimony to support or undermine the credibility, honesty, chastity or peacefulness of a witness. (shrink)

This paper defends the heretical view that, at least in some cases, we ought to assign legal liability based on purely statistical evidence. The argument draws on prominent civil law litigation concerning pharmaceutical negligence and asbestos-poisoning. The overall aim is to illustrate moral pitfalls that result from supposing that it is never appropriate to rely on bare statistics when settling a legal dispute.

Many jurisdictions prohibit or severely restrict the use of evidence about a defendant’s character to prove legal culpability. Situationists, who argue that conduct is largely determined by situational features rather than by character, can easily defend this prohibition. According to situationism, character evidence is misleading or paltry. -/- Proscriptions on character evidence seem harder to justify, however, on virtue ethical accounts. It appears that excluding character evidence either denies the centrality of character for explaining conduct—the situationist position—or omits probative evidence. (...) Situationism is, after all, presented as antithetical to virtue ethics. -/- This essay provides a virtue ethical defense of character evidence exclusion rules. We show that existing virtue ethical rebuttals to situationism themselves support prohibitions on character evidence; even if behavior arises from stable character traits, character evidence should be prohibited. In building our case, we provide a taxonomy of kinds of character judgment and reconcile the ubiquity and reasonableness of character judgments in ordinary life with the epistemic legitimacy of character evidence prohibitions in law. (shrink)

Is it right to convict a person of a crime on the basis of purely statistical evidence? Many who have considered this question agree that it is not, posing a direct challenge to legal probabilism – the claim that the criminal standard of proof should be understood in terms of a high probability threshold. Some defenders of legal probabilism have, however, held their ground: Schoeman (1987) argues that there are no clear epistemic or moral problems with convictions based on purely (...) statistical evidence, and speculates that our aversion to such convictions may be nothing more than an irrational bias. More recently, Hedden and Colyvan (2019, section VI) describe our reluctance to convict on the basis of purely statistical evidence as an ‘intuition’, but suggest that there may be no ‘in principle’ problem with such convictions (see also Papineau, forthcoming, section 6). In this paper, I argue that there is, in some cases, an in principle problem with a conviction based upon statistical evidence alone – namely, it commits us to a precedent which, if consistently followed through, could lead to the deliberate conviction of an innocent person. I conclude with some reflections on the idea that the criminal justice system should strive to maximise the accuracy of its verdicts – and the related idea that we should each strive to maximise the accuracy of our beliefs. (shrink)

The standard of proof applied in civil trials is the preponderance of evidence, often said to be met when a proposition is shown to be more than 50% likely to be true. A number of theorists have argued that this 50%+ standard is too weak – there are circumstances in which a court should find that the defendant is not liable, even though the evidence presented makes it more than 50% likely that the plaintiff’s claim is true. In this paper, (...) I will recapitulate the familiar arguments for this thesis, before defending a more radical one: The 50%+ standard is also too strong – there are circumstances in which a court should find that a defendant is liable, even though the evidence presented makes it less than 50% likely that the plaintiff’s claim is true. I will argue that the latter thesis follows naturally from the former once we accept that the parties in a civil trial are to be treated equally. I will conclude by sketching an alternative interpretation of the civil standard of proof. (shrink)

In this paper I respond to Marcello Di Bello’s criticisms of the ‘normic account’ of the criminal standard of proof. In so doing, I further elaborate on what the normic account predicts about certain significant legal categories of evidence, including DNA and fingerprint evidence and eyewitness identifications.

For the past half-century, both jurisprudence and epistemology have been haunted by questions about why individual evidence (i.e., evidence which picks out a specific individual) can sufficiently justify a guilty or liable verdict while bare statistical evidence (i.e., statistical evidence which does not pick out a specific individual) does not sufficiently justify such a verdict. This thesis examines three popular justifications for such a disparity in verdicts – Judith Jarvis Thomson’s causal account, Enoch et al.’s sensitivity account, and Sarah Moss’ (...) knowledge-first account, before critiquing each in turn. After such an analysis, the thesis then defends the claim that legal verdicts require the factfinder (e.g., the judge or jury) to have a justified de re belief (i.e., a belief about a specific object – namely the defendant), and that this doxastic requirement justifies the disparity in rulings, as it is epistemically insufficient to justify a de re belief based on bare statistical evidence alone. A brief account of how these beliefs are formed and spread is also given. After making such a distinction, the thesis then formalizes the burdens of proof of the preponderance of the evidence and beyond a reasonable doubt using the de re/de dicto distinction. Finally, the thesis pre-empts possible objections, namely by providing an account of DNA evidence as individual evidence and giving an account of how false convictions can occur on the de re view of legal proof. (shrink)