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Political consequences of conspiratorial thinking: evidence from 2016 Italian constitutional referendum


Recently, the literature has devoted increasing attention to beliefs in conspiracy theories. Among various aspects of the phenomenon, it was found that conspiratorial attitudes are associated with political behaviour. In Italy, previous research found that Five Star Movement and right-wing parties' voters tend to show higher levels of conspiratorial thinking than other voters. However, the relationship between conspiracism and vote choice remains obscure. By analysing an Italian panel survey data collected before and after 2016 constitutional referendum, we show that the belief in conspiracy theories is associated with referendum vote choices, even when controlling for partisan opinions, leaders’ evaluations, and perceived economic wealth. Moreover, the effect of conspiracism on referendum vote choice proves to be stronger among the supporters of the government, which promoted the referendum. This paper aims at shedding light on the processes of opinion formation and how these are affected by external attitudes, such as conspiratorial ones.

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    During the referendum campaign, Gustavo Zagrebelsky was even involved in a tv-debate against Matteo Renzi, the leading figure in the campaign for Yes vote. The debate, broadcast on September 30, 2016, by the private channel La7, represented one of the most relevant media events of the campaign.

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    Adusbef is an association for consumers’ protection whose president was the MP Elio Lannutti.

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    Descriptives are computed on the 2,843 individuals interviewed both in the pre- and in the post-referendum surveys.

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    The three items are: parties are necessary to defend special interests of groups and social classes; parties guarantee that people can participate to politics in Italy; without parties there cannot be democracy.


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Correspondence to Moreno Mancosu.

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Mancosu, M., Ladini, R. & Vassallo, S. Political consequences of conspiratorial thinking: evidence from 2016 Italian constitutional referendum. Acta Polit (2020). https://doi.org/10.1057/s41269-019-00146-3

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  • Conspiracy theories
  • Political behaviour
  • Referendum
  • Constitutional reforms
  • Italian politics