In writing The Republican Brain, I had a problem to solve. You see, it was one thing to cite all the psychological research suggesting that liberals and conservatives just think differently, because they have different personalities and cognitive styles. Sure, one could infer on this basis that certain conservatives, especially authoritarian conservatives, would simply be more factually wrong about certain deeply held beliefs. But I also needed evidence from the real world showing that, you know, conservatives or Republicans are more factually incorrect.
That’s where all the fact-checker data came in.
You see, we have paid professionals whose job it is to track just how wrong Democrats and Republicans are. They’re called fact-checkers, and as I show in The Republican Brain (and in this article for The Nation), both PolitiFact and the Washington Post’s fact-checker column do indeed rate Republicans significantly worse than Democrats overall. The data for PolitiFact had already been analyzed before I did the book (see here); I then carried out, with the help of a research assistant named Aviva Meyer, a similar analysis of 315 fact-checks by The Washington Post from 2007 through 2011. And the punchline is the same: Republicans fare worse than Democrats, especially when it comes to the worst ratings (4 Pinocchios, “pants on fire”).
I find these fact-checker data particularly compelling, by the way, for the following reason: Neither PolitiFact nor Glenn Kessler (who writes the Post’s column), think of themselves as liberal partisans. To the contrary, I would argue that both go too far in trying to ding Democrats and liberals, just to make themselves appear balanced (and, presumably, to keep getting their calls returned by the other side of the aisle). Therefore, if their data shows Republicans fare worse, that really says something.