Agreement and DOM with impersonal se: A comparative study of Mexican and Peninsular Spanish

This chapter explores the different properties of impersonal se constructions in Mexican and Peninsular Spanish. Impersonal se requires Differential Object Marking (DOM) with transitive verbs. Contrary to Peninsular Spanish, Mexican Spanish allows agreement with DOM in situ. However, this agreement is blocked whenever DOM is cliticized. This leads to the question of the true nature of DOM and the clitic. The chapter shows that different dialects might show different clitic solutions to DOM in these constructions. These parametric differences can be explained depending on the level of underspecification of the clitic. The difference in availability of agreement of the verb with DOM is due to the availability of an empty clitic head that blocks agreement with DOM in Peninsular, contrary to Mexican Spanish. This difference is further captured in terms of phase theory, since it is assumed that a clitic creates a phase that cannot be penetrated by agreement.