This study explores how academic scientists engage as experts in public debates characterised by scientific uncertainty and societal urgency, focusing on rhetorical positioning and communicative intentions. The research centres around the debate concerning COVID-19 measures in Sweden and analyses 109 opinion pieces written by scientists in various newspapers. The analysis identifies four ideal-typical expert roles: Reformers, Advisors, Informers, and Evaluators. These roles illustrate how scientific expertise can serve multiple purposes in societal crises marked by uncertainty. Reformers take a critical stance, questioning foundational assumptions and advocating for systemic change. Advisors offer actionable recommendations in the face of uncertainty, while Informers contribute by clarifying facts and providing context; Evaluators look back to assess what has worked, guiding future improvements. The typology responds to calls for greater transparency and reflexivity among experts by illustrating the diverse ways scientists assume expert roles in public debate. Recognising the variety and complementarity of these roles and promoting awareness and openness about them can play an important role in sustaining science’s legitimacy amid uncertainty. By shedding light on scientists’ rhetorical positioning and communicative intentions, our framework supports a more structured and nuanced reflection on public engagement. Such awareness is necessary for building and maintaining public trust, particularly during times of crisis.

© The Author(s) 2025.