Party law, or the legal regulation of political parties, has become a prominent feature of party systems. Some party laws are designed to have a much larger political impact than others. It... Show moreParty law, or the legal regulation of political parties, has become a prominent feature of party systems. Some party laws are designed to have a much larger political impact than others. It remains unknown why some countries adopt party laws that have substantial implications for party politics while other countries’ legislative efforts are of a very limited scope. This dissertation explores why different party laws appear as they do. It builds a theoretical framework of party law reform that departs from the Latin American experience with regulating political parties. Latin America is not necessarily known for its strong party systems or party organizations. This raises the important question of why Latin American politicians turn to party law, and to political parties more generally, to structure political life. Using these questions as a heuristic tool, the dissertation advances the argument that party law reforms provide politicians with access to crucial party organizational resources that allow them to win elections and to legislate effectively. It identifies threats to party organizational resources as an important force shaping adopted party law reforms – with potentially damaging consequences for the legitimacy of the political system as a whole. Show less