In the USA, Trump supporters are the most prolific users and sharers of "junk news" (a mix of untruth and distastefully presented materials)
Oxford's Computational Propaganda Project surveyed 13,500 "politically active" US Twitter users and 48,000 publicly visible Facebook pages, coding them for political affiliation, then measuring how much "junk news" (a news article that fails to live up to three or more of the following: professionalism, style, credibility, bias, counterfeit) was consumed and share by users based on their political affiliation.
The researchers concluded that the "extreme hard right" (as distinct from "Republicans") were the most prolific consumers and promulgators of "junk news." The group identified as "Trump supporters" were the worst offenders.
There's an obvious problem with this study, which is that it conflates "lying" with "telling the truth in ways the authors find distasteful." There is a world of difference between untruthful/counterfeit news and news that is "unprofessional" or that has an unlikable "style." It also conflates junk "sites" with junk "stories." A true story is true even if it is told by a habitual liar, and it is a form of ad-hominem itself to disqualify a true story because you don't like the person who's telling it.
On Twitter, the Trump Support Group shares 95% of the junk news sites on the watch list, and accounted for 55% of junk news traffic in the sample. Other kinds of audiences shared content from these junk news sources, but at much lower levels. On Facebook, the Hard Conservative Group shares 91% of the junk news sites on the watch list, and accounted for 58% of junk news traffic in the sample. The coverage and consistency scores for Facebook and Twitter reveal some important features of these platforms when it comes to junk news circulation. The average coverage score for the major audiences of junk news on Twitter and Facebook is 54 and 33, respectively. This means that on average, groups of Twitter share 54% of the junk news watch list and groups of Facebook users share 33%.
The social networks mapped from public Twitter and Facebook data show that the junk political news and information was concentrated among Trump’s supporters. The two main political parties, Democrats and Republicans, prefer different sources of political news, with limited overlap. For instance, the Democratic Party shows high levels of engagement with mainstream media sources and the Republican Party with Conservative Media Groups. On Twitter in particular, the Democratic Party have interacted closely with the Progressive Movements Group, suggesting a broad intersection of interests. On Facebook, most connections between groups conform to the partisan polarization found on Twitter. We also find close interactions between the Occupy Group and the Conspiracy Group.
Polarization, Partisanship and Junk News Consumption over Social Media in the US [Vidya Narayanan, Vlad Barash, John Kelly, Bence Kollanyi, Lisa-Maria Neudert, and Philip N. Howard/University of Oxford Computational Propaganda Project]
Fake news sharing in US is a rightwing thing, says study [Alex Hern/The Guardian]