Remarks such as these typify the school of jurisprudence known as American legal realism. Legal realists regard the law-in-the-books as less important than the law in action —the conduct of those who enforce and interpret the positive law. American legal realism defines law as the behavior of public officials (mainly judges) as they deal with matters before the legal system . Because the actions of such decision makers—and not the rules in the books— really affect people’s lives, the realists say, this behavior is what deserves to be called law.
It is doubtful whether the legal realists have ever developed a common position on the relation between law and morality or on the duty to obey positive law. They have been quick, however, to tell judges how to behave. Many realists feel that the modern judge should be a social engineer who weighs all relevant values and considers social science findings when deciding a case. Such a judge would make the positive law only one factor in her decision.
Because judges inevitably base their decisions on personal considerations, the realists assert, they should at least do this honestly and intelligently. To promote this kind of decision making, the realists have sometimes favored fuzzy, discretionary rules that allow judges to decide each case according to its unique facts.