When Rick Santorum suspended his candidacy for the GOP presidential nomination on Tuesday, he removed any remaining doubt that Mitt Romney would be the Republican presidential nominee. The result is a news vacuum that can easily be filled by spin and misinformation.

Consider the ridiculous debate over comments made on CNN about stay-at-home moms by Hilary Rosen, which dominated the news cycle and the political Twittersphere yesterday. As NBC’s First Read points out, while “manufactured controversies are nothing new in American politics,” what is new “is how much faster and professionalized—due to Twitter and the drive to make something go viral—these manufactured controversies have become.” Such controversies can be especially potent as we enter what First Read calls “silly season.” When few competing stories exist and political reporters are starved for material, any whiff of scandal or controversy can create a feeding frenzy (PDF). A bored media is dangerous for politicians.

In this case, the Rosen controversy, like the “Etch-a-Sketch” flap, is unlikely to have a significant effect on the outcome of the campaign. It was a wasted day for those who produce and consume political news and will probably have few real-world consequences.

That isn’t always the case when journalists flock to a story on Twitter, though. The dynamic we observed when South Carolina governor and potential GOP vice presidential nominee Nikki Haley was smeared on the social network in late March, for example, suggests a troubling potential outcome that campaign reporters should seek to avoid.

As Jeremy W. Peters reported this week in The New York Times, a blog post falsely claiming that Haley would soon be indicted for tax fraud was retweeted by numerous national reporters and commentators. From there, it was linked on the Drudge Report, and the rumor was soon covered in a front-page story in The State, the largest newspaper in South Carolina.

The report was quickly debunked, but the speed with which it circulated echoes similar episodes involving false reports of the deaths of former Rep. Gabrielle Giffords (D-AZ) and former Penn State football coach Joe Paterno.

Should we be concerned about the way the Haley episode played out? Ben Smith, the former Politico blogger who now serves as editor-in-chief of BuzzFeed, offered a counterintuitive defense of the process. “The beauty of all this is the speed of the self-correction,” he told Peters. “If it had been a newspaper report, it could have hung out there for a day.”

But that optimism may be unfounded. It’s too soon to know what damage has been done to Haley’s reputation (I have not been able to locate any public polls that have been conducted since the episode took place). However, research on the psychology of misinformation has found that the effects of false claims on people’s opinions tend to persist even after they are told that the claims are false (PDF). In other words, the most important factor is not how quickly a claim was debunked, but how widely it spread while it was in circulation. Journalists need to start taking accuracy concerns on Twitter more seriously before the next Rosen-style frenzy claims someone else’s reputation.

Brendan Nyhan is an assistant professor of government at Dartmouth College. He blogs at brendan-nyhan.com and tweets @BrendanNyhan.