In one variant of the trolley problem a trolley is rapidly bearing down on the innocent five who can be saved but only by pushing a single fat man onto the tracks. Do you push the fat man or not? The question throws into stark relief the moral theories of consequentialism and deontology.
Now suppose the fat man is named Tyrone. Does that change your answer? What if the fat man is named Chip?
In The Motivated Use of Moral Principles (pdf) the authors show that self-identified liberals are more reluctant to sacrifice Tyrone than Chip despite prior agreement that race is irrelevant to moral questions of this kind. Even more interesting when first presented with the Tyrone story liberals subsequently become less consequentialist even regarding Chip. But when first presented with the Chip story they maintain consequentialism for Tyrone.
On different questions, such as how consequentialist to be in military situations, self-identified conservatives swing back and forth in similar ways depending on whether Americans are attacking or being attacked.
Unfortunately, the authors don't present their statistical results in as clear a form as I would have liked (percentage changes would have been nice) so it's a little unclear how large the effect is. Nevertheless, although the conclusion isn't surprising it's interesting to see these results even in as clean a context as one could ever hope for:
Rather than being moral rationalists who reason from general principle to specific judgment, it appears as if people have a “moral toolbox” available to them where they selectively draw upon arguments that help them build support for their moral intuitions. While the present studies do not imply that general principles never play a direct, a priori role in moral judgment, they do suggest that moral judgments can be influenced by social desires or motivations, and that moral principles can be rationalizations for other causes of the judgment.
Hat tip Psychology Today.