The U.S. Supreme Court and the Model of Contingent Discretion

Abstract

An inherent tension exists between the legislative and judicial branches - Congress initially passes statutes defining particular areas of the law, but the Supreme Court (as the highest judicial authority) has the opportunity to interpret those statutes. This tension caused by the constitutional invitation to struggle over the meaning of the rule of law has profound implications for democratic theory and the separation of powers. Though scholars have examined whether the Supreme Court issues decisions against the preferences of Congress, there has been little focus on whether legislators can constrain the Court. Our paper fills this scholarly gap by employing a measure of statutory constraint that examines how much discretion Congress provides in the statutes it enacts into law. Our basic argument is that ideological decision making by Supreme Court justices is contingent upon the level of discretion afforded by the law. The greater the level of discretion incorporated into a statute by Congress, the less constraint federal judges (and Supreme Court justices) will encounter when they decide cases; consequently the more likely those judges will be to vote according to their individual ideologies. Conversely, more detailed statutes will reduce the level of discretion afforded to judges, and consequently they will be constrained from voting attitudinally. Using data on Supreme Court decisions from 1953-1996, our analysis provides empirical evidence to support our theoretical conceptualization of judicial behavior. If everything else is held equal, the justices will render decisions according to their ideological preferences. Yet, all things are not equal and the presence of legal factors, such as statutory constraint, limits the ability of some justices to rule ideologically. Our findings demonstrate that the presence of detailed statutory language can also facilitate the expression of ideological voting among other justices.