Not at all encouraging, though this explains a lot.
New research, published in the journal Political Behavior last month, suggests that once those facts — or “facts” — are internalized, they are very difficult to budge. In 2005, amid the strident calls for better media fact-checking in the wake of the Iraq war, Michigan’s Nyhan and a colleague devised an experiment in which participants were given mock news stories, each of which contained a provably false, though nonetheless widespread, claim made by a political figure: that there were WMDs found in Iraq (there weren’t), that the Bush tax cuts increased government revenues (revenues actually fell), and that the Bush administration imposed a total ban on stem cell research (only certain federal funding was restricted). Nyhan inserted a clear, direct correction after each piece of misinformation, and then measured the study participants to see if the correction took.
For the most part, it didn’t. The participants who self-identified as conservative believed the misinformation on WMD and taxes even morestrongly after being given the correction. With those two issues, the more strongly the participant cared about the topic — a factor known as salience — the stronger the backfire. The effect was slightly different on self-identified liberals: When they read corrected stories about stem cells, the corrections didn’t backfire, but the readers did still ignore the inconvenient fact that the Bush administration’s restrictions weren’t total.
It’s unclear what is driving the behavior — it could range from simple defensiveness, to people working harder to defend their initial beliefs — but as Nyhan dryly put it, “It’s hard to be optimistic about the effectiveness of fact-checking.”