State Supreme Courts have grown in importance during the last thirty years in the formation of public policy. Their judgements determine many aspects of constitutional law, tort reform, judicial selection, and campaign finance reform, among others. A vast body of literature has been developed that analyzes State Supreme Court decision making, which emphasizes the conditioning effects of the legal and institutional environment. This article expands on this previous work by incorporating the interaction of the judiciary with other government institutions, and applies the Positive Political Theory approach to law and legal institutions to the State Supreme Court. In addition, the neo-institutionalist literature of the selection process is incorporated to defend a systematic approach towards decision making. Towards that end, this article explores how judicial decisions are conditioned by institutional rules, resulting in a formal modeling of how the State Supreme Courts interact with political actors to form constitutional interpretation. This model includes the judicial selection process'retention or competitive reelection—and is extended to constitutional amendment rules, explaining how these two interact rather than acting independently. Finally, the hypothesis is tested that when State Supreme Court judges face retention elections and political preferences are homogeneous, the probability increases of observing constitutional amendment prosposals.
