Checking and Sharing Alt-Facts

Using a randomized experiment in the context of the 2019 European elections in France, we study how fact-checking affects real sharing of "alternative facts" (false or misleading statements by politicians) on Facebook and the determinants of the decision to view the factchecking. We expose over 4200 voting-age French to statements on the role of the EU made by the extreme-right party Rassemblement National. A randomly selected subset of participants was exposed to fact-checking of these statements while another randomly selected subset was offered a choice whether to view the fact-checking or not. Then, all participants were offered an opportunity to share alternative facts on their Facebook pages. Those who saw fact-checking information could also share it on Facebook. We show that: (i) both imposed and voluntary fact-checking reduces sharing of alternative facts by more than 25%; (ii) the size of the treatment effect is similar between these two treatments; and (iii) each additional click required to share alternative facts reduces sharing by 75%.