The US Supreme Court routinely purports to resolve statutory interpretation disputes by deferring to the enactment-era “ordinary,” “public” meaning of the statute’s terms (their “OPM”). In recent years, scholars have begun using surveys and experiments to test judges’ claims about OPM in particular cases, and to critique modern textualist theory and practice more generally. This chapter argues that surveys and experiments can provide highly probative evidence of OPM, whether one favors the more populist conception of OPM on which the modern Supreme Court frequently purports to rely, or the more thoroughly stylized conception that some scholars favor. Drawing on the handful of published survey-experimental efforts to date, and responding to scholarly criticisms of them, the chapter suggests that surveys and experiments may prove too probative for comfort. If modern textualists were to spell out ex ante their conception of OPM with sufficient precision to render it capable, even in theory, of resolving the hard cases they claim it resolves, then survey-experimental data might reveal that the theory produces disappointing results – not just in discrete cases, but across the board.

Psychology and law, by their nature, are deeply entwined. Both are about human behavior – understanding it, modifying it, regulating it. Psychology’s research engagement with legal topics enjoys a long history, but until recently has been largely limited to clinical assessment (e.g., capacity, insanity) and police and trial evidence and procedures (e.g., eyewitnesses, jury instructions). The traditional canon of “Psychology & Law” research gained prominence when DNA evidence revealed that many wrongful convictions involved problems foreseen by psychologists. Also, the emergence of “Behavioral Law & Economics” likely provided more legitimacy to law’s engagement with empirical psychology topics and methods, spurring “Law & Psychology” teaching and research in law schools. The expanded range of research can be found across the US law curriculum as illustrated in four main first-year courses – Criminal Law, Torts, Contracts, and Property – and two commonly taken or required courses – Evidence and Professional Responsibility. The current experimental jurisprudence boom has added to the topics and methods used in this research and amplifies the existing trend in which psychology engages more closely with the content and values of law.

The present chapter presents an overview of the recent applications of experimental methods to jurisprudential issues in international law as well as potential future developments of the field. We discuss how experimental methods can helpfully contribute to the understanding of the different moments of international law: the making of new rules, the interpretation of these rules, and, finally, their application in practice. We also present three main topics that constitute the studies of rule application in practice, namely, the mechanisms behind human judgment, policymaking, and, finally, the decision taking itself. We identify some future potential lines of development based on the example of the current disagreements over the definition of an international crime of “ecocide” and discuss some potential limitations of the experimental approach.

Experimental jurisprudence draws methods and theories from an increasingly wide variety of fields, including psychology, economics, philosophy, and political science. However, researchers interested in legal thought have thus far paid relatively little attention to its origins in development. This chapter highlights an emerging approach that leverages methods and insights from developmental science to better understand the nature and development of adult intuitions about the law. By studying children’s earliest intuitions about rules, laws, and other topics, this “intuitive jurisprudence” approach can provide new methods and theoretical frameworks for experimental jurisprudence, as well as clarify places in which the law does or does not match human intuitions about justice. Already, developmental psychology and legal scholarship may converge to be mutually informative in a number of diverse areas, and this chapter reviews several, including: intent and punishment; fairness and procedural justice; ownership and property rights; trust in testimony and evidentiary issues; and social biases and equal protection under the law.

Legal language is often ambiguous. Consider: “Only cars and trucks with permits are allowed.” Does [PP with permits] have “wide scope” over the entire series [NP cars and trucks] or “narrow scope” over only the closest noun, [trucks]? Judges often choose narrow scope, citing a legal canon, the “Last Antecedent Rule.” But they sometimes choose wide scope, referencing the “Series Qualifier Canon,” which assigns modifiers to a series. Though judges claim to want to use “most people’s” interpretations, these conflicting choices led us to ask “What WOULD most people say?” We ran three experiments to find out.

Overall, wide scope was preferred. With biased PPs, the preference dropped slightly when the bias matched the last noun, “[NP cars and trucks] [PP with trailers],” but not the first, “[NP trucks and cars] [PP with trailers],” where a universal syntactic “No Crossing Branches principle” limits the PP’s domain. With temporal PPs, “People may park [NP cars and trucks] [PP on weekends],” the preference was also uniformly wide scope, not surprisingly, since these PPs can only modify verbs, not nouns. Taken together, our experiments show how experimental psycholinguistics can offer powerful evidence about how “most people” understand legal language, important information for judges and lawmakers alike.

Rules are ubiquitous. They figure prominently in all kinds of practical reasoning. Rules are especially important in jurisprudence, occupying a central role in answers to the question of “what is law?” In this chapter, we start by reviewing the evidence showing that both textual and extratextual elements exert influence over rule violation judgments (Section II). Most studies about rules contrast text with an extratextual element identified as the “purpose” or “spirit” of the rule. But what counts as the purpose or the spirit of a rule? Is it the goal intended by the rule maker? Or is purpose necessarily moral? Section III reviews the results of experiments designed to answer these questions. These studies show that the extratextual element that’s relevant for the folk concept of rule is moral in nature. Section IV turns to the different explanations that have been entertained in the literature for the pattern of results described in Sections II and III. Finally, in Section V we discuss some other extratextual elements that have been investigated in the literature. We conclude with a brief discussion of future directions.

As a branch of analytic philosophy, jurisprudence, understood as legal philosophy, is often thought to be a nonempirical enterprise. It turns out, however, that unresearched, unsupported, and largely impressionistic empirical assertions have long been a part of the analytic jurisprudential enterprise. Recognizing this is the first step towards examining and testing these empirical assertions. Using the proclivity of ordinary people to obey the law (or not) because of the content-independent existence of law as one example of such an assertion, this chapter explores how that assumption might be tested by experimental and other means, as a prolegomenon to testing the empirical claims and assumptions that have long pervaded even the most traditional jurisprudence.

Legal concepts can sometimes be unclear, leading to disagreements concerning their contents and inconsistencies in their application. At other times, the legal application of a concept can be entirely clear, sharp, and free of confusions, yet conflict with the ways in which ordinary people or other relevant stakeholders think about the concept. The aim of this chapter is to investigate the role of experimental jurisprudence in articulating and, ultimately, dealing with competing conceptual inferences either within a specific domain (e.g., legal practice) or between, for example, ordinary people and legal practitioners. Although this chapter affirms the widespread assumption that experimental jurisprudence cannot, in and of itself, tell us which concepts should be applied at law, it highlights some of the contributions that experimental jurisprudence can, in principle, make to normative projects that seek to prescribe, reform, or otherwise engineer legal concepts. Thus, there is more that experimental jurisprudence can normatively offer than has usually been claimed.

Legal rights, obligations, and liabilities bind together entities, including people, real and moveable property, and abstract objects, across time. Determining whether these rights, obligations, and liabilities exist at any particular time therefore requires the law to embed within it a theory of persistence – that is, a theory of how entities persist over time. The philosophical and psychological literature has identified multiple different theories of how objects persist over time, some of which are identity relations and some of which are not. Research in experimental jurisprudence has shown both that ordinary people’s judgments about the law often match the content of the law itself and that ordinary people’s judgments appear sensitive to multiple different persistence relations. These findings provide reason to think that the law, to the extent it reflects the judgments of ordinary people, also reflects multiple different theories of persistence – contrary to recent arguments that legal rights depend solely on numerical identity.

This chapter briefly introduces experimental jurisprudence and the contents of the handbook.

The law and corpus linguistics movement shares many of the commitments of experimental jurisprudence. Both are concerned with testing intuitions about legal concepts through the lens of empirical evidence gathered through experimentation. Though often discussed in the context of a given case or legal problem, linguistic evidence from legal corpora can help provide content to otherwise indeterminate concepts in the law.

Using language evidence from linguistic corpora, we can begin to have more meaningful conversations about what concepts like ordinary meaning, ambiguity, and speech community might actually mean and make progress on the boundaries of these concepts and their implications for legal interpretation. And, because corpora are constructed from linguistic utterances made in natural linguistic settings, they can provide an important check and means of triangulation for experimental jurisprudence claims that are often premised on survey data.

In this chapter we ask if people have rights to their social identities – in particular, their gender identities. We cash out what such gender identity rights entail by discussing the appropriate level of constitutional scrutiny to apply to laws that target transgender people.

This chapter discusses the promise and the pitfalls of conducting social psychological research on mock jurors. The tremendous potential of this methodology to shed light on the psychology of jury decision-making is only beginning to be tapped. We use two recent experiments on the psychology of character assessments as case studies to explore some of the necessary tradeoffs in this methodological design, and to showcase the importance of understanding the psychological underpinnings of our legal doctrines. However, future research must present more diverse stimuli that better reflect the racial and gender composition of parties in real trials. Recognizing how hard it can be to replicate complex psychological processes experimentally, we argue that in some cases we should switch the burden of proof – that is, near-universal psychological processes should be presumed to also occur in the courtroom.

A writer, a theorist, and an empiricist walk into a book. They muse about how the law might influence people’s moral intuitions. Their dialogue touches on recent studies exploring such an effect in moral dilemmas. As they ponder the possible feedback loop between law and morality, they also wonder: What might happen when people feel that a disfavored law – such as a ruling by a disfavored court – does not really count as law at all?