Public Sphere in Crisis Mode: How the COVID-19 Pandemic Influenced Public Discourse and User Behaviour in the Swiss Twitter-sphere.

In modern democracies, large societal crises like the COVID-19 pandemic are accompanied by intensified public discourse about which policies and strategies are adequate to fight the crisis. In such times, the public sphere switches to crisis mode with fundamentally different communicative dynamics compared to routinised periods. Data from social media platforms like Twitter offers new possibilities to study such dynamics. However, comprehensive studies on how crises affect discourse in distinct national publics are missing up to now. Based on 1,762,262 tweets referring to COVID-19 written between 1 January and 30 April 2020 by 56,418 validated Swiss users, we illustrate how the lockdown of public life in Switzerland affected the discourse in the Swiss Twitter-sphere. Based on public sphere theories, we identify four crisis-related dimensions for our analysis. We show that the pandemic led to a narrowing of the topic agenda and to a more inwardly oriented public sphere with increased Twitter activity by experts. Furthermore, actors from the social periphery were able to reach the centre of public discourse with their tweets. Overall our study shows how methodological innovation allows us to better connect an empirical analysis with the concept of a public sphere as a communication network.