Case Sensitivity Reflects Case Structure: Agreement, Extraction, and Clitics

A variety of syntactic phenomena seem to be conditioned by morphological case (an effect known variously as `case discrimination', `case targeting', `case opacity', or simply `case sensitivity'). In this talk I address three such phenomena---phi-agreement, A' movement, and clitic-doubling---with the eye to two related questions: What is the representation of (marked) case on a nominal? And how are syntactic operations sensitive to this representation? In place of the relatively standard view of case as a feature on a DP, I argue that a full understanding of case sensitivity in syntactic operations calls for a view of (marked) case as a structure around DP, i.e. a KP. Treating case assignment as structure addition, and case sensitivity as structure sensitivity, I show how we can capture proposed hierarchies of case sensitivity in phi-agreement (Bobaljik 2008) and A' movement (Otsuka 2006), as well as a novel case-hierarchy effect in the realm of clitic-doubling.