Buffalo Law Review

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This Article aims to create a complete typology of the forms of decisional law. Distinguishing “rules” from “standards” is the most commonly attempted jurisprudential line, roughly drawn between nonvague and vague. But no agreement exists on the dimension along which the rule/standard terminology lies, or on where the dividing line on the continuum lies. Thus, classifying in terms of vagueness is itself vague. Ultimately it does not aid legal actors in formulating or applying the law. The classification works best as an evocative image.

A clearer distinction would be useful in formulating and applying the law. For the law-applier, it would be more useful if expressly focused on whether the law-giver was trying to pin things down and thus narrow the room for discretion. For the law-giver, it would be more useful if it had helped to think about how to pin things down.

This better top-level distinction divides binary from scalar directives. If the directive comprises a checklist of one or more yes/no conditions, then it is a binary directive. If instead the directive calls for consideration of multivalent factors, it is a scalar directive. First, binary/scalar is a superior distinction for analysis because it is a clean distinction. Second, it is a telling distinction that represents a significant difference between the components that compose the law. Third, it tells the law-applier much about whether the law-giver tried to pin things down. Fourth, it conveys a better sense of the tools at hand for the law-giver’s pinning down the law-applier, and thus enables the tools’ deployment in an optimal way. Fifth, it allows the drawing of meaningful subdivisions that bring to the fore the choices in shaping that law: for example, one such subtype of scalar directives is a true balancing test, which explicitly or implicitly presents an exhaustive listing of quantifiable and commensurable considerations to be scaled and weighed against one another—and so offers a route to retrieving some control in the application of any scalar directive.

Parenthetically, a running example to illustrate the superiority of binary/scalar comes from injunctive relief. The test for a temporary restraining order was the supposedly binary condition of “irreparable harm,” but it has disintegrated in practice to the prevailing test for a preliminary injunction. The diversity among the tests for preliminary injunctions reveals the essential struggle between the necessary flexibility for infinitely variable situations and the need for appropriately corralling the judges’ discretion. From ancient roots of unrestrained discretion, the test for a preliminary injunction has evolved in recent decades from a sequential test of four supposedly binary conditions to the indefiniteness of a sliding-scale approach that balances the so-called four factors, back to a hopeless stab at crispness in the form of the alternatives test that tries to state alternative combinations of situational facts warranting provisional relief. The best test emerges as a systematized form of scalar directive—a true balancing test—that asks if the expected costs of a potentially wrongful denial exceed the expected costs of a potentially wrongful grant of a preliminary injunction. The inadequacy of the current rule/standard distinction for this analysis reveals itself in the fact that it would probably categorize all the competing preliminary injunction tests as “standards.”

In the end, this Article does not propose casting rule/standard aside as a way of evocatively classifying decisional law. Instead, it proposes adopting binary/scalar as the way technically to define rules and standards: a rule appears as a yes/no checklist, and a standard involves a subjective or multidimensional scalar measurement.