Several scholars agree that low political trust has fundamental negative implications for society at large. This study tests the power of institutional performance theory in explaining the differences between individuals in political trust (cross-sectional) and fluctuations of political trust over time (longitudinal). Indeed, the dominant scholarly debate has concerned whether political trust is stable and dependent of endogenous factors such as political socialization and social trust, or whether it is exogenous (i.e., in constant fluctuation due to later experiences with institutions and the outputs they produce). In terms of cross-sectional differences, the aim is to assess the relative impact institutional performance on political trust of a citizen. As regards the longitudinal approach, political trust varies over time and from an explanatory perspective it is important also to understand how well the institutional performance theory predicts over-time variation of political trust. The study employs repeated European Social Survey data for Finland between 2004 and 2013. The results show, first and foremost, the strong impact of evaluations of institutional performance on political trust: satisfaction with government and economy explains differences both between individuals and over time. Social trust and welfare state performance are also strong predictors, but they explain differences only at the individual level and do not predict over-time variations.
