Exceptional case-marking (ECM), in linguistics, is a phenomenon in which the subject of an embedded infinitival verb seems to appear in a superordinate clause and, if it is a pronoun, is unexpectedly marked with object case morphology (him not he, her not she, etc.).
The term ECM itself was coined in the Government and Binding grammar framework[1] although the phenomenon is closely related to the accusativus cum infinitivo constructions of Latin.
Both types of analysis show a relatively flat structure insofar as the material in bold consists of two separate sister constituents.
The more layered analysis has the advantage that it accommodates the insight that the subject/object constituent is a semantic argument of the infinitival verb.
The flat analysis has the advantage that it is more consistent with data delivered by operational considerations: the object morphology on the pronoun (e.g. him, her, them, etc.
), the ability of the object/subject to become the subject in the passive counterpart (e.g. That was proved to be true), the obligatory appearance of the reflexive pronoun when coindexation occurs with the subject (e.g. They1 judge themselves1/*them1 to be important), and the inability of constituency tests to clearly identify a clausal constituent (e.g. Topicalization: ?