Dunning & Kruger strike again.

Dunning–Kruger effect is that "idiots think they are geniuses - because they are idiots".

The case in question is "bigots think they are unbiased because they are bigots".

Specifically, in How Social Science Might Be Misunderstanding Conservatives, the very liberal author admits that

Within social psychology, there is something like a 14-to-1 ratio in favor of liberal-identifying researchers relative to conservative-identifying ones.

and then dismisses the claim of liberal bias in academia as overstated.

However, a growing insurgency claims that

Liberal psych researchers, centering their work on liberal values and political opinions, have built up a body of knowledge that is fundamentally flawed and biased.

Final gem:

the so-called C-scale developed ... in the 1960s, ... describe[d] as “the psychological instrument that has been most widely used to measure conservatism.” It consists simply of 50 items where the respondent circles “yes” or “no” to indicate whether they “favor or believe in” the item in question. For scoring purposes, saying you dislike jazz contributes just as much to your designation as a “conservative” than saying you are in favor of the death penalty, despite the fact that one item is clearly an example of ideological conservatism and the other is, well, whether you like jazz.

More details are in Rethinking the rigidity of the right model: Three suboptimal methodological practices and their implications.