Person case constraint effects in Polish copular constructions

The paper examines two patterns found in one type of copular constructions in Polish, i.e., those containing the verbal copula by´ 'be' and the pronominal copula to. In the first pattern the verb by´ 'be' agrees with the second, postverbal element, not with the first one, while in the other 1st and 2nd person pronouns are banned from appearing as the first elements in to bycopular clauses. It is argued that these apparently unrelated patterns are amenable to a uniform analysis couched within the minimalist approach to the Person Case Constraint (henceforth, the PCC). This approach crucially relies on the application of multiple Agree and the assumption that in Polish, just like in other languages, T probes separately for person and number. It is argued that in both patterns under consideration T probes the first DP for person and the second one for number and gender, which accounts for agreement with the second element in the first pattern. If the first DP is 1st or 2nd person, it values the person feature of T as 1st or 2nd and this is responsible for a person clash if the second DP is marked for 3rd person, which accounts for the second pattern. The analysis offered predicts that the two DPs in to byclauses must match in person. It is shown that this prediction may turn out to be problematic in the light of the fact that identity statements and inverted copular sentences allow person mismatch. It is argued that although they seem to be problematic in fact neither in the former nor in the latter the mechanism underlying the PCC effect, i.e., multiple Agree, is operative, but for a different reason. Equatives are analysed along the lines proposed by Perelstvaig (2001; 2008) for Russian and Italian by Moro (1997; 2006), i.e., they are treated as bare small clauses which lack a label unless the second DP is internally merged with the bare small clause and thus provides it with a label (DP). As a result of this movement, the moved DP is closer to the probe T than the other DP, which blocks multiple Agree. In inverted copula sentences, on the other hand, parallel probing by T and C applies, which forces the movement of the inverted element to Spec CP and thus makes it unavailable to Agree with T.