Agreement and unlocking at the edge

A growing body of work argues that Agree has the effect of “unlocking” certain domains, phases, such that otherwise illicit extraction from them becomes permitted (Rackowski & Richards 2005, van Urk and Richards 2015, Halpert 2016, 2018, Branan 2018). First, we address when such unlocking is required. While some works argue that unlocking is only needed for extraction from deep within a phase, others argue that all extraction requires it. We argue in support of the former view, based on Chichewa facts reported in Mchombo (2004, 2006). Second, we consider the relationship between unlocking effects and phase theory more generally. We argue that the possibility of unlocking indicates that material deep within a phase must not be rendered inaccessible by spellout, or else unlocking effects should be impossible. We explore how unlocking might be handled in the cyclic linearization theory of phases (Fox & Pesetsky 2005, a.o.) which leaves syntactic elements accessible post-spellout.