Increased pressure lowered trust among unvaccinated during the COVID-19 pandemic: Effects of the announcement of reintroducing vaccination passports in Denmark

During the COVID-19 pandemic, the imposition of moralistically justified costs on unvaccinated individuals was used to incentivize vaccination uptake. Here, we ask whether such a strategy creates adverse consequences in the form of lowered trust in the pandemic response among unvaccinated individuals, which could jeopardize their compliance with the broader set of health interventions. As our empirical case, we use a press conference held by the Danish government on 8 November 2021, where COVID-19-vaccination passports were reintroduced, in part, to pressure unvaccinated people to take up the vaccine. We analyse the effects of the press conference using daily, nationally representative survey data (total N = 24,934) employing a difference-in-differences design. We demonstrate that the press conference decreased the trust in the pandemic management by 11 percentage points among unvaccinated individuals, while trust remained high among vaccinated individuals. Moralistic cost imposition also reduced collective action motivation and coping appraisal among unvaccinated individuals, and, while it increased societal threat appraisal among vaccinated people, it failed to do so among unvaccinated individuals. Our findings imply that decision-makers using moralized cost imposition as a health intervention should be aware of its potential unintended adverse consequences.