Does Joining the European Union Affect Institutional Trust in Post-Communist Countries? An Application of the Synthetic Control Method

Abstract: This paper applies the synthetic control method, a statistical methodology for empirical case studies, to examine the effect of EU accession and EU negotiation status on trust in institutions in post-communist European countries. For each examined unit, the method produces a synthetic control unit from a pool of similar countries. The post-treatment trajectories are then compared to establish a treatment effect. A treatment effect cannot be established at the time of EU accession. However, a treatment effect is found at the time of EU negotiation status for one of the treated units, Croatia. No treatment effect can be established at the time of EU negotiation status for the other treated unit, Montenegro.