On case concord: the syntax of switch-reference clauses

This paper discusses switch-reference (SR) systems in Pano and Muskogean languages, and proposes that grammatical case plays an essential role in licensing same-subject SR constructions in these languages. Specifically, case activates an agreement relationship between two clauses, allowing for transmission of information about participant coreference. different-subject SR, on the other hand, does not involve case concord, but signals the activation of a discourse participant that was either inactive in the background or not present.