How do political parties respond to street protest by political outsiders widely considered to be ‘pariahs’ (i.e. radical or extremist actors)? Bridging the literature on responses to ‘populist’ radical right parties with insights from social movement studies, we propose a theoretical model that conceptualises potential party responses to pariah protest. Innovatively, our typology distinguishes between a set of formal and substantive responses to street mobilisation. Empirically, we apply this model by providing the first systematic study of how political parties have responded to the ‘anti-Corona’ protests of Querdenken, contributing to social science research on the politics of the COVID-19 pandemic. Analysing the critical case of Germany, we underline the stark difference between how the populist radical right AfD and all other Bundestag parties respond to anti-Corona mobilisation, showing how political protest may sharpen the polarisation of party politics. Moreover, we highlight the more nuanced but still important differences in responses by established German parties. Theoretically, the article provides an analytical framework valuable in times of increasing street mobilisation by radical and extremist actors. Methodologically, our analysis relies on a systematic media analysis of articles from two major German newspapers. Empirically, it contributes to our understanding of the difficult but crucial relationship between the German protest and party arena during the COVID-19 pandemic.