How Policy Defection and Political Compromise Affect Ideological Perceptions of Representativeness

How do policy defection and compromise among member parties of coalition governments affect a voter’s ideological perceptions of their party? I argue that perceptions of representativeness, or congruence, of the party shift when the party participates in political compromise as voters observe the party’s performance as a member of a governing coalition. The causal mechanism operates through ideological updating: when voters learn about their party’s compromise, they update beliefs about where the party stands on the ideological spectrum, thereby changing how well they feel represented. I test this mechanism in the context of Italy using a pre/post vignette survey experiment examining subject perceptions and support of their party regarding asylum seeker policy. I find that individuals update their perceptions about the ideological positioning of their party after they learn about policy defection, and this effect is moderated—but not eliminated—when they simultaneously learn about political compromise. When compromising parties also defect from voter expectations, subjects report feeling less supportive of their party serving as a member of a governing coalition, feel less close to their party, and feel less represented. Together, these results clarify the causal mechanism linking political compromise to governing costs, with implications for understanding when and why coalition democracy becomes unstable.