Brendan Nyhan

From my new Upshot column:

A lot of time and effort has been spent correcting the falsehoods, lies, rumors and conspiracy theories promoted by politicians during this election — most notably by Donald J. Trump. Does it do any good? Or have we entered a “post-fact” age?

In some cases, research I have conducted with the political scientist Jason Reifler has found that correcting people’s false beliefs can be ineffective or, worse, make them cling to their views even more strongly.

However, other research we have done suggests that fact-checking can be effective. The political scientists Thomas Wood and Ethan Porter have also found corrective information is generally effective in reducing false beliefs, though the extent to which it is effective can depend on people’s political views.

The four of us decided to evaluate the effectiveness of corrective information in reducing misperceptions during this election.

From my new Upshot column (co-authored with Kyle Dropp):

Hillary Clinton and President Obama are outraged about the F.B.I. director James Comey’s decision to disclose further inquiries into her handling of confidential email, but are the American people?

Although numerous prosecutors and former Department of Justice officials have accused Mr. Comey of violating formal guidelines and informal norms against commenting on continuing investigations or publicizing political cases just before elections, voters do not seem to share their indignation.

From my new Upshot column (co-authored with Kyle Dropp):

America’s most prominent birther has finally disavowed the myth he helped to create. Will Donald J. Trump’s concession affect the public’s belief about whether President Obama was born in the United States?

Results from a new Morning Consult poll of registered voters suggest that fewer Americans now believe that President Obama was born outside the country — the false claim that Mr. Trump renounced last Friday — although birtherism continues to linger among a subset of the public.

From my new Upshot column:

Hillary Clinton undoubtedly had a tough weekend, but how much will it affect the election?

On Friday night, Mrs. Clinton said half of Donald J. Trump’s supporters belonged in “the basket of deplorables” — “racist, sexist, homophobic, xenophobic, Islamophobic.” Survey data suggests that a substantial fraction of Mr. Trump’s supporters do hold deeply negative views of several demographic groups, but after heavy criticism she said, “I regret saying ‘half’ — that was wrong.”

Then on Sunday, Mrs. Clinton staggered in public. Following hours of uncertainty, her campaign disclosed that she had previously been diagnosed with pneumonia, prompting renewed questions about her health and her secretive tendencies.

Both episodes are receiving extensive news media coverage, but past experience shows that what many consider to be gaffes typically have very limited effects on the actual vote. Candidate health issues, however, could be more unpredictable.

From my new Upshot column:

Anyone who has followed this election carefully would be forgiven for thinking that voters have diverged into two separate realities. But it’s too soon to declare that we have entered a “post-fact” apocalypse, especially when we consider where people get information about politics.

New research shows that the great majority of people learn about political news from mainstream, relatively centrist media sources, not ideological websites or cable channels. However, relatively small numbers of partisans, especially Republicans, are heavy consumers of a highly polarized media diet.

This dynamic helps explain why there is so much concern about “echo chambers,” even though most people don’t confine themselves to one.

From my new Upshot column:

As public support turns against him, Donald Trump is suggesting without evidence that the election could be “rigged” by Democrats using vote fraud. This claim threatens the norms of American elections and could provoke a damaging reaction among his supporters.

Ultimately, democracies depend on losers’ acceptance of the legitimacy of the political process. That’s why the norm of accepting election outcomes among defeated presidential candidates is so important.

From a new Monkey Cage post co-authored with my former students Sasha Dudding and Heather Szilagyi:

Last month, the House Intelligence Committee released a previously classified section of the 2002 congressional inquiry into the September 11 attacks known as the missing “28 pages.” The U.S. government allegedly kept this document confidential to protect its relationship with Saudi Arabia. Instead, the move ended up fueling a massive controversy centered on claims of a cover-up by the U.S. government intended to suppress evidence of Saudi complicity in the 9/11 attacks.

Our research helps explain why withholding information from government documents like the “28 pages” is so often counterproductive. In a new article (written with co-authors at Dartmouth College) in the Journal of Experimental Political Science, we show how the use of redactions can undermine the effectiveness of documents intended to reduce belief in conspiracy theories. Keeping information from the public can create the perception of a cover-up even when none exists.

Our post is based on our new article in the Journal of Experimental Political Science (ungated), which was co-authored with the students in my 2014 Experiments in Politics seminar:

Classified or Coverup? The Effect of Redactions on Conspiracy Theory Beliefs

Brendan Nyhan, Franklin Dickinson, Sasha Dudding, Enxhi Dylgjeri, Eric Neiley, Christopher Pullerits, Minae Seog, Andy Simpson, Heather Szilagyi and Colin Walmsley

Conspiracy theories are prevalent among the public. Governments frequently release official documents attempting to explain events that inspire these beliefs. However, these documents are often heavily redacted, a practice that lay epistemic theory suggests might be interpreted as evidence for a conspiracy. To investigate this possibility, we tested the effect of redactions on beliefs in a well-known conspiracy theory. Results from two preregistered experiments indicate that conspiracy beliefs were higher when people were exposed to seemingly redacted documents compared to when they were exposed to unredacted documents that were otherwise identical. In addition, unredacted documents consistently lowered conspiracy beliefs relative to controls while redacted documents had reduced or null effects, suggesting that lay epistemic interpretations of the redactions undermined the effect of information in the documents. Our findings, which do not vary by conspiracy predispositions, suggest policymakers should be more transparent when releasing documents to refute misinformation.

From my new Upshot column:

In declaring himself “the law and order candidate” in his convention speech Thursday night, Donald Trump officially made crime one of his core issues. This emphasis is relatively new, and it’s strategic.

From my new Upshot column:

The F.B.I. recommendation on Tuesday not to file charges against Hillary Clinton for what the director James Comey called her “extremely careless” email practices has set off a debate over whether there was any partisan influence in the case.

The issue came to the fore last week when news broke that former President Bill Clinton had boarded Attorney General Loretta Lynch’s plane. Though both sides insisted they had not discussed the case against Mrs. Clinton, the resulting furor prompted Ms. Lynch to vow to accept the recommendation of career prosecutors and the F.B.I. on whether to file charges.

In his announcement of the recommendation, which is likely to be endorsed by prosecutors at the Department of Justice, Mr. Comey said that the investigation had not been subject to outside influence.

Mr. Comey’s claim carries credibility given his status as a Republican who served in the George W. Bush administration. The case was also extraordinary in its level of importance and scrutiny — which may have created pressure to avoid any appearance of affecting the November election — and may not fit previous patterns. However, the historical record suggests that politically sensitive cases are often not immune from politics, especially in the timing of when they are resolved.

From my new Upshot column:

Donald Trump keeps making promises that experts don’t think he can possibly fulfill. It might seem that he has people fooled by his implausible claims, which include pledges to make Mexico pay for a border wall and to bring manufacturing jobs back to the United States. The psychologist David Dunning, for instance, has suggested that many voters are backing Mr. Trump because they lack the expertise to recognize his mistakes.

But in some news reports, his supporters sound more realistic about what Mr. Trump, the presumptive G.O.P. nominee, could accomplish as president.