Populist Contagion in the House of Commons: Extent, Content, Mechanisms, and Conditions

Ebru Ece Özbey

Several studies to date have argued that politics in Western liberal democracies have become gradually populist since the 1990s, not only due to the increasing number of populist parties, leaders, and movements but also to their mainstream competitors, who have followed suit. The empirical evidence concerning populist contagion has remained inconclusive, however, and the existent literature has focused predominantly on electoral performance and support as the focus of inquiry, political parties as the unit of analysis, and a priori identification of cases through literature reviews, expert interviews, or surveys. This dissertation project sets out to revisit the theoretical arguments on populist contagion beyond the party-political sphere while questioning the alleged linear and one-directional (from populist towards mainstream) pattern of contagion. It adopts a non-normative, narrower definition of populism and perceives the phenomenon as a matter of degree rather than with a dichotomous either/or approach. Focusing on the textual data from parliamentary debates alongside other qualitative and quantitative data sources and using a mixed-methods research design, it measures populism at the individual as well as aggregate level and reveals the temporal trends of "populistization" for the period between 1997 and 2017. Furthermore, it unravels the specific content(s) of different populist manifestations, explores the stylistic ornamentation of populist communication, and ascertains the mechanisms of and conditions for populist contagion.