Rude but Right? Emotions, Message Alignment, and the (Un)Persuasive Power of Incivility

Despite the rise of incivility - conceptualised as disrespectful, impolite, and vulgar language - in political discourse, its persuasive impact, particularly for congruent messages, remains contested and understudied, especially outside the United States. By persuasive impact, we mean the ability of incivility to change attitudes. We argue that incivility is not an objective reality but a subjective, perceptual construct: what is considered “uncivil” depends on who receives the message and on their pre-existing beliefs. However, incivility perceptions - i.e., how uncivil or impolite one believes a behaviour to be - are incomplete without considering incivility evaluations, that is, how appropriate or entertaining one believes this behaviour to be. This distinction is essential as it allows us to fully capture the normative assessment of incivility. As a result, incivility perceptions and evaluations are tied to individual predispositions as well as to the nature of the message itself, namely, whether it aligns or conflicts with the recipient’s own views. Message congruence is an important moderator as it enables us to understand whether partisans can potentially accept some forms of incivility and therefore, whether incivility may become normalised in our political discourse. Thus, we investigate how the interplay between message alignment and the degree of incivility jointly shapes the persuasive impact of incivility, as well as the perception, evaluations, and emotional responses elicited by these messages. For the scope of this paper, we focus on elite-level incivility, that is incivility expressed by political elites and how individuals receive it. Two competing theoretical expectations are tested. On the one hand, social identity theory suggests that uncivil congruent messages may trigger moral backlash for violating in-group norms. On the other hand, motivated reasoning implies that these messages are tolerated due to partisan biases. We posit that the degree of incivility matters: cruder forms of impoliteness may be more strongly perceived and thus punished, whereas milder cases may be tolerated when they come from one’s own side. This enables us to understand the bounds of norm enforcement especially for ingroup partisans and which degree of incivility may be detrimental to public discourse. We conduct a 2 (message alignment: in favour of vs against stance) x 3 (incivility: civil, mild, high incivility) between-subjects experiment in Switzerland, France, and Germany (N = 3,000). By examining these dynamics across three national contexts with distinct political cultures, this study provides insights into when incivility backfires, when it is dismissed, and its emotional repercussions –specifically, moral indignation. It offers a novel, comparative test of incivility’s effects, moving beyond U.S.-centric findings and refining theories of motivated reasoning and norm enforcement. This allows us to identify the conditions under which partisan incivility is normalised – and acceptable - or sanctioned.