When Corruption Investigations Come to Nothing: A Natural Experiment on Trust in Courts

Anti-corruption investigations often undermine public support for political authorities while increasing that of judges and prosecutors. However, what happens when investigations fail to result in actual sanctions? Is citizens’ trust in the legal system undermined? Does that depend on their co-partisanship with the investigated politicians? Or is the lack of sanctions taken as “business as usual”, particularly in contexts where impunity is perceived as endemic? These rival hypotheses are examined taking advantage of an April 2021 decision to drop corruption charges against former Portuguese Prime Minister José Sócrates during a public opinion survey’s fieldwork. Employing an Unexpected Event during Survey Design approach, we show that the decision had a large negative immediate impact on public trust in the legal system.