Behavioral Jurisprudence: Law Needs a Behavioral Revolution – By Benjamin van Rooij & Adam Fine

Laws are supposed to protect us. At work, they should eliminate unsafe working conditions and harassment. On our streets, they should curb speeding, distracted driving, and driving under the influence. And throughout our countries, they should protect citizens against their own governments.

The law is the most important behavioral system we have. Yet it is designed and operated by behavioral novices. Lawyers draft legislation, interpret rules, and create policies, but legal training does not teach them how laws affect human and organizational behavior.

Law needs a behavioral revolution, like the one that rocked the field of economics. There is now a large body of empirical work that calls into question the traditional legal assumptions about how law shapes behavior. This empirical work also offers a path forward. It can help lawyers and others shaping the law understand the law’s behavioral impact and help align its intended influence on behavior to its actual effects.

There is now a large body of empirical work that calls into question the traditional legal assumptions about how law shapes behavior.

For instance, the law has traditionally focused on punishment as a means to deal with harmful behavior. Yet there is no conclusive evidence that threats of incarceration or fines reduce misconduct. Most people do not understand or know the law, and thus never come to weigh the law’s incentives in deciding whether to comply with it.

The law also fails to account for the social and moral factors that affect how people interpret and follow it. For instance, social norms—what people see others do or think others hold they should do—can shape what we think the laws say. Research also shows that people are more likely to follow rules they deem legitimate, and that rules that are made and enforced in a procedurally just and fair manner enhance compliance.

And, traditionally, the law has focused on motivational aspects of wrongdoing. But behavioral responses to the law are highly situational. Here, work in criminology, particularly within environmental criminology, shows that criminal opportunities are a chief driver of criminal behavior. Relatedly, when people have their needs met, for instance when they have a livable wage or sufficient schooling, they are more likely to follow the law.

These important empirical insights have yet to shape mainstream thinking about the law. We need a behavioral jurisprudence that corrects assumptions about the law’s influence on human behavior. But simply presenting empirical evidence is not enough. There are deeper, implicit tenets in legal thinking that obstruct the adoption of a scientific approach.

We need a behavioral jurisprudence that corrects assumptions about the law’s influence on human behavior.

For lawyers, the law is a very special object. It is what they are trained in, what they understand, practice, and shape. When thinking about behavior, lawyers tend to assume that the law’s text alone is what is going to drive human behavior. Yet most people do not have the fine details of the law in mind when they make decisions. Most people do not know criminal law, basic employment rights or family law, or the law specific to their professions. So a behavioral jurisprudence requires a less law-centric and more practical view of how people interact with the law.

Similarly, most legal research and education focuses on normative questions, developing arguments about what the law is and should be. This ignores the crucial question of effectiveness, of understanding whether laws actually deliver justice, which is what matters to most people. To understand how laws translate into a sense of justice, we must understand how legal rules structure the motivations and situations that shape behavior. Unfortunately, in political debates about legislation, disputes in court, or law school discussions, such empirical questions often exist only on the periphery. If discussed, they do not receive the methodological and theoretical attention they deserve. A true behavioral jurisprudence would move beyond a normative view of law to also embrace empirical questions of the law’s cause and effect.

A true behavioral jurisprudence would move beyond a normative view of law to also embrace empirical questions of the law’s cause and effect.

Finally, lawyers and politicians shaping the law place an outsized influence on the past. Lawyers are trained to interpret the law based on past court cases and legislative history. In litigation, lawyers deal with liabilities that revolve around disputes after they occurred. And debates about new legislation, which seeks to regulate future behavior, dwell on examples from the past. But for law to fulfil its function, it cannot simply react to harmful behavior after it occurs; it must reduce and prevent it ex ante. The law must move beyond understanding how to respond to the singular case and shift to investigating law’s effects on a large range of future cases to prevent harm in the first place. This requires an understanding of the science of human behavior and integrating it into the process of creating legislation. 

It is time for a behavioral revolution in the field of law. It is time our most important behavioral system operates with a knowledge and evidence base suited to its task. It is time for a behavioral jurisprudence, a movement that leverages empirical approaches to law and human behavior to create a more just, fair, and effective legal system.