The test results baffled Florida State University psychologist Ashby Plant. She checked and rechecked the figures. Something must be wrong, she told herself.

Plant and her colleagues had just administered a racial Implicit Association Test to 74 white college students. A common tool in psychology lab work, the IAT purports to measure the kinds of biases people may not admit or even know they harbor. It is one of the more troubling, and fascinating, realities in Plant’s line of work that when the test is administered to whites, about 75% typically show some degree of anti-black bias.

But in this case, her subjects were displaying almost no bias against African Americans. In fact, about 45% appeared to be favoring blacks over whites.

“It made us stop dead in our tracks,” she said. “I mean, this was unheard of.”…

At Stanford University, researchers led by graduate student Daniel Effron found what might be called a reverse Obama effect. In their studies, white Obama supporters showed favoritism for whites over blacks in certain hypothetical situations — perhaps because by supporting Obama, they felt bestowed with non-racist “moral credentials” that made them more comfortable siding with fellow whites.