Philosophy needs a methodology, including rules about burden of proof, in order to resolve many of its classic issues. Law might seem to provide a helpful model for assigning burdens of proof. However, candidate rules that distribute burden of proof according to form, degree of belief, and consequences all fail to help when inspected closely. This gap makes it difficult to see how to resolve many of the most important philosophical issues.

Enforcement is costly, so sometimes states choose not to enforce their laws. We study this choice under rules and under standards. We show that nonenforcement of rules sends a relatively clear signal about state capacity. Regulated parties can use this information and violate law to some extent with impunity. Nonenforcement of standards sends a noisier signal, and this uncertainty may cause regulated parties to comply with law even though the state lacks capacity to enforce, a surprising implication. According to conventional wisdom, standards are costlier to enforce than rules, meaning a switch from rules to standards should decrease compliance. However, we argue that standards, by obscuring the state’s capacity, can increase compliance. We identify the characteristics of standards that yield these effects, and we show that the logic generalizes to the complexity of law as well as its precision.

This Essay focuses on and expands Schauer’s justification for the rules of evidence. To that end, I present Schauer’s fundamental idea that establishes the necessity of rules in the domains of morality, politics and law while responding to the challenge of act-utilitarianism. In addressing that challenge, Schauer famously singled out the principal-agent settings featuring asymmetrically informed rule-maker and rule-applier and then demonstrated that rules have the ability to minimize this asymmetry—a social benefit that offsets the costs incurred by the over- and under-inclusiveness of the rules. After explaining this insight, I move the discussion to legal epistemology and examine how Schauer connected the “necessity of rules” thesis to the law of evidence. Based on Schauer’s work that established this connection, I identify reasons that can and cannot justify factual findings in adjudication.

Fred Schauer’s work on probability and evidence exposes a persistent problem for criminal law: credible allegations of sexual assault routinely fall short of proof beyond a reasonable doubt, leaving serious wrongdoing unaddressed. Schauer highlights this failure through cases involving probabilistic aggregation, but ultimately locates the payoff of his analysis outside criminal adjudication. This Article returns the argument to where it belongs – within the criminal law. Deploying Schauer’s own analytical toolkit, it examines three potential levers – the burden of proof, the construction of criminal offenses, and evidentiary rules – that could be used to respond to the injustice of sexual violence. For each, it details the difficult trade-offs between protecting defendants and vindicating victims. There is no clear winner.

What is unprincipled adjudication and when, if ever, is it justified? In addressing those questions, this essay attempts to complete a project begun with Professor Fred Schauer.