This dissertation addresses three broad questions in political sociology: How do the structures of political institutions shape political conflicts? How are social cleavages (race, class, etc.) linked to conflicts between political parties? And why do states vary in their capacity to make and implement political decisions?

I develop a theory of political decision-making by drawing on the work of Max Weber, political institutional theories, and other sources. The overall argument is that states’ ability to reach decisions (such as creating new laws) is influenced by three factors: 1) the number and location of veto points, 2) the pattern of partisan control, and 3) the extent of alignment of partisanship with social and ideological cleavages. Many veto points, divided partisan control, and a strong link between partisanship and cleavages lead to a high level of political gridlock.

Budget gridlock in California provides a perfect case for assessing my theory of political decision-making. From 1970 to 2010, California’s government was increasingly unable to enact budgets on time. However, since 2010, it has enacted all of its budgets by the deadline. I use comparative-historical methods to examine the rise and fall of budget gridlock.

Broadly speaking, I find that the conjuncture of three factors drove the rise of budget gridlock from 1969 to 2010: the establishment of supermajority rules within the government; divided partisan control of government positions; and increasing polarization of Democrats and Republicans along demographic and ideological lines. Changes in two of these factors - the elimination of the supermajority rule for passing budgets, and the shift to full control of the budget process by Democrats – largely account for the disappearance of gridlock since 2010. These findings provide support for my theory of political decision-making.

The theory that I develop in this dissertation offers a much stronger explanation for political gridlock than existing models in political science. It can be used to improve our understanding of gridlock in the U.S. federal government, the states, and in other settings. More broadly, it is useful for explaining both the dynamics of political conflicts and variations in state capacity in a variety of contexts.