Boundary Work and Problematised Contestation: Reconfiguring the Cordon Sanitaire in the European Parliament

Research on norm contestation frequently assumes, implicitly or explicitly, that contestation and contesters are normatively negative. While much scholarship acknowledges that contestation can also strengthen legitimacy, most of the time researchers are interested in assessing the damage done by contestation. This paper takes a step back and asks about the ways in which contestation is constructed in the first place, and as different from legitimate disagreement. This is particularly relevant in a moment in which the distinction between contesters and contested has become increasingly blurred as the identity and characteristics of contesting actors shift. In the EU, actors previously positioned outside the normative “in-group” are now shaping mainstream discourse, while mainstream actors are being sidelined. The boundaries dividing legitimate agreement from illegitimate contestation seem to be changing too. How can we conceptualise the changing relationship between the EU’s normative core and those who challenge it? This paper proposes a new theoretical approach to understanding this shift by applying the concept of boundary work to the study of contestation in the European Parliament. It argues that the erosion of the cordon sanitaire is best understood not simply as strategic accommodation or ideological convergence, but as the product of dynamic boundary-making practices that reshape how political actors define “acceptable” and “unacceptable” positions within the EU’s normative community. Boundary work explores how contesting actors can reposition themselves, and be repositioned, within an evolving political landscape. This approach is based on a combination of two existing frameworks. First, Wimmer’s (2008) taxonomy of boundary-making strategies highlights how boundaries shift through changes in topography (where boundaries are drawn) and membership (who belongs inside them). Second, Haker & Otterspeer’s (2020) application of Müller’s three populist dimensions (content, social practice, and rationality) provides a way to map how political actors enact their positioning within or outside a boundary. Integrating these approaches produces a multi-dimensional tool for analysing how the political mainstream and right-wing populist actors redraw the boundaries of the normative in-group. Empirically, the paper applies this framework to analyse contestation of EU climate and gender norms between 2009 and 2024. Using critical discourse analysis of plenary debates and speeches from the EPP and key PRR parties, the study tracks how boundaries of content, social practice and rationality shift over time, and how these shifts contribute to the mainstreaming of RWP discourse. The empirical application provides an additional level of analysis of contrasting issues. Both climate and gender issues show different patterns of contestation over time, largely due to the normalisation of long-standing disagreements on gender norms in contrast to recent politicisation of climate issues. The paper also investigates why these differences produce varying levels of boundary resilience. It offers broader insights into institutional resilience, the future trajectory of right-wing populism in Europe, and the EU’s capacity to sustain its normative authority in an increasingly contested political environment.