Working Paper

Abstract

What role do journalists play in how political debates are portrayed in mainstream news coverage? We answer this question using data on climate change in Congressional floor speeches and in mainstream and partisan US newspapers from 2012-2022. We find that Republican lawmakers primarily discuss the costs of climate regulation while Democrat lawmakers primarily discuss the urgency of climate action. However, the climate debate in mainstream newspapers is predominantly focused on urgency. We propose a theory of journalist selection, arguing that this effect is driven by journalists increasingly self sorting into newsrooms based on their perceived ideological position. We find that journalists who join mainstream newspapers later are more likely to focus on urgency and less likely to focus on economic costs in their articles compared to older journalists in the same year, newsroom, and section. However, the opposite pattern holds for journalists who join far right partisan newspapers.