Defining Spheres of Influence: The Intersection of Spheres of Argument and Amicus Curiae Briefs in the State Court Debate Over Same Sex Marriage

Erica Lynne Delgadillo, University of Colorado Boulder


In 1982 Goodnight introduced the concept of personal, public, and technical argument spheres to rhetorical scholars which quickly supplanted Toulmin’s argument fields. While not intended as merely a typology for argument, argumentation scholars have repeatedly applied the spheres in this manner, obscuring the important aspects of argument. In order to demonstrate how reliance upon spheres precludes a clear understanding of arguments, this study focuses on a particular social controversy—same sex marriage. The debate over same sex marriage has held our nation’s collective attention for over three decades. While the debate has been carried out in our public spaces, much of the change in the status of same sex couples has resulted from state court decisions. Because the debate over same sex marriage represents the confluence of the multiple perspectives regarding private and public rights, many organizations have contributed to the legal debate in the form of amicus curiae briefs. To demonstrate the lack of explanatory power of argument spheres, I explore the amicus curiae briefs submitted to several state courts of last resort. Not only do these briefs represent a shift in legal argument, they illustrate the problems created for scholars when Goodnight’s spheres are misappropriated. I argue that scholars should return to close readings of arguments in the context of the social controversy.