In this paper, we show how some proposals within the Minimalist Program are compatible with a model of codeswitching that recognizes an asymmetry between the participating languages, the Matrix Language Frame model. Through our discussion of an analysis of NPs in a Spanish–English corpus, we illustrate this compatibility and show how recent minimalist proposals can explain the distribution of nouns and determiners in this data set if they adopt the notion of Matrix Language as the bilingual instantiation of structural uniformity in a CP. We outline the central premises of the Matrix Language Frame model, and introduce the Uniform Structure Principle which requires that the structure of constituents be uniform at an abstract level. We then review previous applications of the Minimalist Program to codeswitching.

Much recent research in minimalism has focused on issues related to feature checking. Earlier approaches to feature checking required matching of features in grammatical structures, although more recent proposals consider distinctions in the values of features and in types of matching. Because phi-features for grammatical gender in Spanish and English differ, an analysis of NPs in this corpus of naturally occurring Spanish–English conversations provides a test for minimalist applications to codeswitching. We present our general findings of the distribution of types of NP constituents and then consider explanations of these distributions in light of minimalist proposals. It is possible to explain these distributions in a recasting of the Matrix Language Frame model in minimalist terms, if the construct of the Matrix Language is maintained. The requirement that one language, the Matrix Language, provide an abstract grammatical frame in bilingual constituents corresponds to the type of uniformity that Chomsky (2001) suggests is necessary for the explanatory study of language and variation in language.