Political parties are more than key players of democratic politics under the law of democracy. In addition to acting behind the scenes of election lawmaking, political parties regulate themselves in the name of ''party autonomy,'' and the extra-legal self-regulations they make often have external effects on the democratic political process as a whole. The most important function political parties perform is to select candidates for electoral competition, and how parties regulate candidate selection in general and candidacy in particular exemplifies their role as co-regulators of electoral democracy. Using Taiwan as a case study, this article explores how partisan self-regulation of legislative candidacies has diversified and complicated the qualifications for representatives. It also attempts to grasp the normative significance and implications of partisan rules by theorizing a pluralistic account of democratic authorities and election lawmaking: the pluralism of the law of democracy. By taking pluralism seriously, this article aims at shedding new light on the regulatory roles of the state, the courts, and political parties in advancing electoral integrity.