In Choctaw, a Muskogean language spoken today in Mississippi and Oklahoma, many verb roots participate in a transitivity alternation. However, different intransitive (henceforth 'non-active') verbs have different interpretations. In particular, some have inchoative interpretations and others have passive-like interpretations. Following much work on the semantics of passives and inchoatives across languages, I assume that these two interpretations are distinguished by, at least, the presence vs. absence of an implicit agent. I provide two diagnostics for the presence of an implicit agent in Choctaw, and a further two diagnostics for the absence of one. I then show that some non-active verbs pass both sets of diagnostics - that is, they may introduce or lack an implicit agent depending on context. With this small typology in place, I provide an analysis that employs root-conditioned contextual allosemy of a specifierless Voice head. The analysis captures not only the semantic properties of non-actives, but also their morphology uniformity and their non-productivity.