Agree and person hierarchy effects in German copular clauses

Recent work on person hierarchy effects has argued that constraints on combinations of internal argument clitics in some languages (the Person Case Constraint) are also evidenced in some languages in binominal copular clauses, in particular ruling out cases where the subject is 3rd person and the “predicate” a 1st or 2nd person pronoun. Copular clauses in German have been argued to exhibit this constraint (Coon & Keine 2021). In this paper we describe experimental data from German that shows that any effect is very weak, contrasting this with observations that have been made for Hindi-Urdu (Bhatia & Bhatt 2023). Further, our data do not show any evidence for an ameliorating effect of syncretism, contra the predictions of accounts that derive ungrammaticality in these cases from problems of morphological exponence. We speculate instead that any effect of person hierarchy in German copular clauses is pragmatic in nature.