In contrast to the predominant ways new dictatorships were formed in the 20th century, most new autocracies in the 21st century arise when elected leaders dismantle democracy from within. This project posits that personalist political parties – or parties that exist primarily to further a leader’s personal political career rather than advance policy – are the key agent that enables democratic backsliding and collapse. Using original, global data on personalism in ruling political parties in the past three decades, we carefully document the process through which this occurs. We argue that personalist parties lack both the incentive and capacity to push back against leaders’ efforts to expand executive power. Without the constraint of the party, leaders of personalist parties are more likely to dismantle institutional checks on the executive in a variety of domains. We further demonstrate that such attacks on state institutions reverberate throughout society, deepening political polarization and weakening supporters’ commitment to democratic norms of behavior. Thus, the underlying cause of democratic collapse lies less with mass publics’ support for illiberal leaders, which is endogenous to backsliding itself, and instead can better be explained by the key mobilizing agent that dismantles democracy from within: personalist political parties.

scoco@ceibs.edu