Climate change communication and public engagement in interpersonal deliberative settings: evidence from the Irish citizens’ assembly

Citizens are being increasingly called upon to participate in climate change policymaking. Citizen assemblies have been proposed as a viable and effective way of boosting public support for ambitious climate policies. This study examines the varying effects of climate change communication on citizen support for the speaker's policy proposals, in the framework of the most consequential citizen-centred experimentation in environmental policymaking to date - the Irish Citizens' Assembly. Drawing on the six-principle framework for authors of the Intergovernmental Panel on Climate Change (IPCC), we test whether effective communication contributes to explaining outcomes of deliberation on climate change. Methodologically, we take a set-theoretic approach, using fuzzy-set qualitative comparative analysis (fsQCA) to operationalise conditions and analyse the data. Our findings show that effective communication does explain why certain policy proposals were adopted by the Irish Citizens' Assembly over others, in conjunction with other conditions, such as having a high proportion of proposals being repeated by other speakers. Key policy insights Citizen assemblies and other deliberative fora can boost public support and provide legitimacy for ambitious climate policy. The information presented to participants in such fora has an effect upon engagement with, and support for, policy proposals. It is not climate change information per se, but how it is communicated that matters for participants' uptake of ambitious climate measures. Speakers who communicate effectively see greater uptake of their policy proposals. Differences exist in the paths to success for expert and non-expert speakers. While the former were successful when they presented a high number of proposals, the latter were successful when they presented a simple, unique message. Organisers of citizens' assemblies should encourage the participation of such non-expert speakers who can connect with audiences on 'real-life' climate action.