If you are watching the current political fiasco known as our presidential election, and wonder why politicans would so prone to make erroneous claims (ie lie) that can be easily refuted, check out this study of how people's opinions were changed when given claims, and then refutations of those claims.
"In experiments conducted by political scientist John Bullock at Yale University, volunteers were given various items of political misinformation from real life. One group of volunteers was shown a transcript of an ad created by NARAL Pro-Choice America that accused John G. Roberts Jr., President Bush's nominee to the Supreme Court at the time, of "supporting violent fringe groups and a convicted clinic bomber."
A variety of psychological experiments have shown that political misinformation primarily works by feeding into people's preexisting views. People who did not like Roberts to begin with, then, ought to have been most receptive to the damaging allegation, and this is exactly what Bullock found. Democrats were far more likely than Republicans to disapprove of Roberts after hearing the allegation.
Bullock then showed volunteers a refutation of the ad by abortion-rights supporters. He also told the volunteers that the advocacy group had withdrawn the ad. Although 56 percent of Democrats had originally disapproved of Roberts before hearing the misinformation, 80 percent of Democrats disapproved of the Supreme Court nominee afterward. Upon hearing the refutation, Democratic disapproval of Roberts dropped only to 72 percent.
Republican disapproval of Roberts rose after hearing the misinformation but vanished upon hearing the correct information. The damaging charge, in other words, continued to have an effect even after it was debunked among precisely those people predisposed to buy the bad information in the first place."
That should have intuitive appeal: we are all guilty of cherry-picking our data, giving unwarranted credibility to that which confirms our bias, and heaping undue skepticism on that which we already doubted. And once an idea gets into our heads, it is sometimes hard to get out. However, there was an additional effect, known as the "backfire effect", where people's opinion's on a subject would move in the opposite direction of the data refuting it, and it was not spread evenly across the political spectrum.
"Bullock and others have also shown that some refutations can strengthen misinformation, especially among conservatives.
Political scientists Brendan Nyhan and Jason Reifler provided two groups of volunteers with the Bush administration's prewar claims that Iraq had weapons of mass destruction. One group was given a refutation -- the comprehensive 2004 Duelfer report that concluded that Iraq did not have weapons of mass destruction before the United States invaded in 2003. Thirty-four percent of conservatives told only about the Bush administration's claims thought Iraq had hidden or destroyed its weapons before the U.S. invasion, but 64 percent of conservatives who heard both claim and refutation thought that Iraq really did have the weapons. The refutation, in other words, made the misinformation worse.
A similar "backfire effect" also influenced conservatives told about Bush administration assertions that tax cuts increase federal revenue. One group was offered a refutation by prominent economists that included current and former Bush administration officials. About 35 percent of conservatives told about the Bush claim believed it; 67 percent of those provided with both assertion and refutation believed that tax cuts increase revenue.
In a paper approaching publication, Nyhan, a PhD student at Duke University, and Reifler, at Georgia State University, suggest that Republicans might be especially prone to the backfire effect because conservatives may have more rigid views than liberals: Upon hearing a refutation, conservatives might "argue back" against the refutation in their minds, thereby strengthening their belief in the misinformation. Nyhan and Reifler did not see the same "backfire effect" when liberals were given misinformation and a refutation about the Bush administration's stance on stem cell research."
If you have been watching the battle against the lies Palin and McCain has been spinning, this should come as no surprise. I would attribute it to the growing paranoid nature of conservatives, where criticism, especially from untrusted sources, equates to confirmation in their mind. Thus, if Media Matters criticizes something Sarah Palin says, that is processed as a confirmation, because of course every good conservative knows that the liberal media is out to get them. We see similar reasoning among Intelligent Design proponents. Since the scientific establishment is out to get them, any proclamations from said establishment is more proof they are right. One can also see this in the common refrain, from both the political and scientific right, that anger from one's opponents means one's arguments are sound. Those in the right, it is assumed, don't get angry or "negative".
This is why the refutations of right-wing political nonsense must come from those not considered "liberals" by the right-wingers, and why ads like this one featuring people like Rachel Maddow will not be effective.