Public authorities supplement routine government functions by building infrastructure, maintaining bridges, building stadiums and convention centers, managing public housing, and running mass transit systems. These special purpose governments are a fixture of urban development and service delivery. Drawing on a framework informed by theories of public authorities and intergovernmental politics, this study examines how statewide public authorities interact with localities and what the implications are for intergovernmental politics and local democratic planning. This research focuses on a state public authority in New York State responsible for economic development: the Empire State Development Corporation. Through archival analysis, interviews, legislative review, and document and project analysis, I show that when a public authority carries out economic development, it can facilitate local economic development planning by overcoming local political inertia, or it can hinder a locality’s planning efforts by substituting statewide economic development interests for local interests. In both cases, there is a negative effect on local democratic processes. By overriding local laws, acting in isolation from the public and the legislature, and allowing the businesses community special access to the public authority, the public authority subverts deliberative and inclusive democratic processes. This study concludes by suggesting ways that public authorities can take up democratic planning principles.