Cordons sanitaires or tainted coalitions? The electoral consequences of populist participation in government

An increasing literature has studied the recent growth of populist parties and the determinants of their electoral success. This article contributes to this body by addressing the question of whether cordon sanitaires or tainted coalitions are more effective at hindering the electoral success of populist parties. Building on the populist parties and cost of governing literatures, we hypothesize that populist parties suffer considerable loses at the ballot box when they join coalition governments as junior partners. Moreover, we test various mechanisms for this negative effect: poor economic conditions, the existence of parliamentary majorities, ideological extremism and low intra-cabinet conflict. Using data from ParlGov and Klüver and Spoon, we find strong support for the main hypothesis, and additional analyses suggest that when populists join coalitions as junior partners they lose extra electoral support if they are ideological extreme, there is low intra-cabinet conflict, or their coalition has a parliamentary majority.