Les tempêtes médiatiques en période électorale : effets sur les médias, sur les dynamiques de construction de l’ordre du jour et sur les citoyens

The purpose of this doctoral dissertation is to assess the linearity of electoral agenda-building dynamics. To that end, the concept of media storm is used. A media storm can be defined as an explosive increase in news coverage of a specific item (event or issue), which garners a substantial share of the total news agenda during a certain time. Recent analyses on the subject suggest that media storms cause changes in the attention patterns of political actors and the media and that they may disrupt the usual power dynamics delineating the reciprocal influence between their respective agendas. Empirically examining agenda-building dynamics during the 2015 Canadian federal election, this study examines the impact of media storms on the three types of actors at the core of any political communication process: the media, the political actors, and citizens.  First, the effects of media storms on election coverage by the media are evaluated. Three media storms were detected during the 2015 Canadian election, and they extended for more than half of the 79-day length of the campaign. One finding is that storm periods decrease the average number of issues present in daily media coverage of the campaign, as the media focus their attention on items related to the storm. Another finding is that parties are more likely to interact with a storm issue during its respective storm period.  Second, the idea that media storms negatively affect political actors’ electoral agenda-building efficiency is tested. Specifically, how storm periods impact the ways in which parties’ attention to given issues promotes their next-day importance in the media’s agenda is examined. Results suggest a significant drop in this salience transfer mechanism during storm periods, when political actors are less successful in their efforts to promote issues unrelated to the storm. They also indicate that parties’ attention to storm-related issues is not guaranteed to raise their profile in the next day’s media agenda, even during storm periods. These findings suggest that agenda-building dynamics are not linear; some contexts are more amenable to successful influence by parties than are others.  Third, how media storms, through agenda-setting and a priming mechanism, affect citizens’ political attitudes and vote choice is investigated. Using the case of the “refugee crisis,” how the storm’s emergence brought changes in opinions about items related to the prominent frames invoked in the competition for the definition of the issue is detailed. Partisan identity is shown to have a significant mediating role in this influence process. Compelling empirical evidence is also offered about the ways in which the storm gradually increased the impacts of those attitudes on vote choice during the 2015 Canadian election campaign.  The dissertation offers an exciting contribution to the literature on media storms – which had never been examined in an electoral context – and on agenda-building dynamics. More generally, it provides novel, and potentially far-reaching, insight on the well-known aphorism that the best election campaign always stays “on message.”

Keyphrases: Media storms, Agenda-Building, Priming, Electoral Campaigns, Mass media, Political Communication, Political Parties