Abstract
This essay analyzes how the borders between the technical and the public sphere were argumentatively demarcated in the B-06 lumpectomy controversy. Drawing from Thomas Gieryn's metaphor of “cultural cartographies of science,” it tracks the implications of four discursive maps of scientific practice that circulated in argument spheres as the controversy unfolded. Considered together, these maps preserved institutional jurisdiction over decision making and missed a critical opportunity to address stakeholder concerns about scientific practice more meaningfully. This case study suggests the need to extend our understanding of argument spheres in science-based controversy.