Partisan Media Ownership, News Content, and Policy Preferences

Abstract

We study how partisan newspaper ownership shapes news content, media demand, and policy preferences. Our setting is the 2010 takeover of the Basler Zeitung, a leading Swiss regional daily, by owners affiliated with the conservative Swiss People's Party (SVP), and its 2018 sale to a nonpartisan media group. We combine over three million articles from six German-language Swiss newspapers with municipality-level circulation data and outcomes from 160 federal referendums over twenty years. Using difference-in-differences designs that compare the Basler Zeitung to control group newspapers and exploit cross-municipality variation in pre-takeover penetration, we trace the effects of ownership along the full chain from content to readership and voting. Partisan ownership shifts coverage toward the SVP platform, especially before referendum votes and on party-sponsored proposals. Circulation declines by 28.8 percent during partisan ownership. Losses are largest in historically left-aligned municipalities, but exposure to the newspaper remains substantial even there. At mean pre-takeover penetration, partisan ownership increases SVP-aligned vote shares by 0.34 percentage points across all referendums, implying a persuasion rate of 14.6 percent among retained, persuadable readers, with larger effects for referendums closely tied to the party platform. Overall, ownership induces both ideological sorting in media demand and persuasion among voters who remain exposed, with political effects concentrated in local environments where SVP positions are more prevalent or less strongly opposed.

Keywords: Media bias, Persuasion, Ideological sorting, Policy preferences, Media ownership

JEL Classification: D72, L82, D83, L15