We are exploring different aspects of the general schema for dependent case assignment given in (1):

(1) If XP bears c-command relationship Y to ZP in local domain WP, then assign case V to XP.

In the last chapter, I presented some evidence that c-command is indeed crucial to dependent case assignment, and I surveyed the different c-command relationships that languages can make use of in their case-assigning rules. A second aspect of this schema that calls for clarification – and where we might look for parameterization – is the local domain WP which must contain both XP and ZP in order for dependent case to be triggered. That is the topic of this chapter.

Marantz’s (1991) original outline referred to domains in two ways. First, he recognized that case assignment is local to (roughly) the clause. For example, the subject and the object of a single clause interact case theoretically, but the subject of a matrix clause and the subject of an embedded clause typically do not. More specifically, he said that one NP causes dependent case to be assigned to another when both are “governed by the [same] VþI complex.” Second, he envisioned the possibility that different cases might be assigned within different kinds of phrase. In particular, the unmarked case for a single NP in a clause might be nominative/absolutive, whereas the unmarked case for a single NP in a complex nominal might be genitive. Generalizing on this, we might expect two sorts of domain effect. First, there might be some variation across languages in whether phrase WP counts as a domain for dependent case marking at all. Second, given that WP counts as a domain, the particular cases that are assigned in relevant c-command configurations might vary with the category of WP. Indeed, we could see this type of variation in dependent case rules as well as in unmarked case rules.