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?

How may experimental jurisprudence contribute to legal questions or advance legal scholarship? This chapter provides a preliminary perspective from German criminal law with a focus on the specific legal practice of doctrinal reasoning (Rechtsdogmatik). It has not been in the focus of experimental jurisprudence, which is understood broadly as empirical studies with laypersons and experts about various legal questions. It overlaps with the classic field of psychology and law, but it is primarily interested in addressing normative aspects. German law is one of the main civil law systems, with firm roots in Roman law. German criminal law has noticeable influence on numerous legal systems throughout the world, from South America to Japan. The following thus hopes to promote the dialogue between these systems and between them and the common law jurisdictions.

In an 1870 essay, Oliver Wendell Holmes, Jr. made a series of penetrating observations about the common law that can still be profitably used by researchers in experimental jurisprudence today. First, Holmes observed that common law reasoning is a process in which judges decide the case before determining the principle on which that decision rests. Second, he suggested that this decision is typically fast, easy, and intuitive, while finding its rationale is often slow, difficult, and deliberate. Third, Holmes noted that this behavioral pattern applies not only to judges and lawyers, but to “other men,” that is, to human beings generally. Fourth, he observed that legal intuitions are often correct, whereas the reasons first offered to explain and justify them are often mistaken. Fifth, he suggested that common law reasoning can be modeled as a practical syllogism. Finally, Holmes implied that the common law is not a body of rules existing “outside the head” of those who discern and apply them, but a mental capacity or psychological entity of some sort. Each of these points anticipated key insights associated with strands of Legal Realism, and each offers valuable lessons for experimental jurisprudence.

We review experimental research on judicial decision-making with a focus on methodological issues. First, we argue that only experiments with relatively high realism, in particular real judges as study subjects, plausibly generalize to judicial decision-making in the real world. Most experimental evidence shows lay subjects to behave very differently from expert judges in specifically legal tasks. Second, we argue that studying the effects of non-law is not a substitute for studying the effects of law since large unexplained residuals could be attributed to either. Direct experimental studies of the law effect are few and find it to be puzzlingly weak. Third, we review the substantive findings of experiments with judges, distinguishing between studies investigating legal and nonlegal factors and paying close attention to the nature of the experimental task.

Settlement, not trial, is the predominant way in which most legal disputes are resolved. Despite this, very little research has examined how the public thinks about settlement. This chapter discusses the need for such research and describes the first few projects trying to fill that need. People hold complex and fairly accurate beliefs about the nature and prevalence of settlement. They also show remarkable willingness to draw inferences when parties settle, including inferences about a defendant’s responsibility. Some avenues for the future of this burgeoning field are also discussed.

Most of the contracts we sign are standard form consumer contracts. Also known as boilerplate or fine print agreements, these uniform “one-size-fits-all” agreements are the most common type of economic contract, used for billions of commercial transactions each year. As this chapter will highlight, experimental research has the potential to significantly inform the regulatory discourse about consumer contracts by providing evidence as to the problems that consumer contracts generate, as well as to the effectiveness of the regulatory tools currently implemented (or under consideration) in addressing these problems. This chapter reviews existing experimental scholarship on consumer contracting with the goal of elucidating its contributions to our knowledge, while at the same time highlighting what remains to be done. Its focus is on experimental studies involving three main issues: (1) consumers’ contracting realities – how consumers behave around form contracts; (2) consumer psychology – how consumers perceive form contracts and the law governing them; and (3) how different regulatory interventions could refashion these contracting realities.

Bias is a topic that has received intense academic study, but its importance within experimental jurisprudence has yet to be unpacked. To fill this lack, we make the following contributions in this chapter. First, we situate the topic within this newly named – but not necessarily new – academic movement: We present recent research on bias in the law and discuss whether it rightly fits within the remit of experimental jurisprudence. Second, continuing to draw on this recent research, we unpack issues that inhere to explorations of bias, ones that are important for understanding, in the experimental jurisprudence context, participants and the data they generate as well as researchers and the data they garner and interpret. Finally, we conclude by offering words of caution and guidance as bias research within experimental jurisprudence progresses.