Locality and variation in Finnish structural case

Finnish has both nominative and genitive objects. The two cases are normally in a complementary distribution based on the local syntactic context (Jahnsson's Rule). The pattern breaks down in nonfinite clauses where the conditioning is non-local and the cases may occur in free variation. This puzzling pattern can be understood if we make the following assumptions: (i) structural case distinguishes the external argument from other arguments; (ii) structural case assignment is cyclic. In our optimality-theoretic analysis the choice of case is determined by the interaction of markedness constraints that apply cyclically and faithfulness constraints that protect case assigned on prior cycles. Non-locality arises because faithfulness is violable; free variation arises because constraint conflicts can be resolved in multiple ways. In addition to categorical well-formedness contrasts the analysis predicts degrees of well-formedness in cases of free variation.