In Chapter 1, I used as a paradigm context in which a strong rule is needed a judge's decision to enforce a bank's right to foreclosure despite unfortunate consequences in the individual case. The rule was supported by consideration of the cumulative effects on financial institutions and the practice of mortgage loans of judges acting on direct moral perceptions in such cases. I also suggested there that this sort of case could be generalized to a blanket duty of judges to defer to clear legal requirements even when they morally disagree with the outcomes of applying law in particular cases. Once again, while individual decisions on grounds of direct moral perceptions have minimal effects on the legal and political systems, the cumulative effects of allowing such decisions when opposed by law would nullify democratic institutions and must be avoided. Finally, I noted there that this fundamental moral rule for judges does not imply that the legal requirements to which they are to defer must themselves take the form of genuine rules.

Our questions for this chapter concern the extent to which legal norms do and should take this form. It is widely assumed, perhaps in contrast to the private moral sphere, that the need for uniformity and predictability in the legal system, and for limiting the power and discretion of those entrusted to enforce the law, means that legal requirements must typically be cast in the form of genuine rules.