"In one study, researchers used computers to generate several faces that were exactly the same except..."

“In one study, researchers used computers to generate several faces that were exactly the same except for the skin color — half were black and half were white. All respondents (yes, including black people studied for the project) were more likely to rate the black faces as showing greater hostility. In another study, scientists showed a group of subjects a video of one person pushing another person. When the “shover” was black and the “victim” was white, 75 percent of research subjects said the push was aggressive. When the “shover” was white and the victim was “black,” only 17 percent of subjects said the push was aggressive. Implicit racial bias has also been found in what researchers call a “shooter bias” — in which subjects playing a simulated video game are more likely to mistakenly pull the trigger on unarmed black men than on unarmed white suspects. The phenomenon has been tested and proved with police officers, too.”

- Trayvon Martin, Obama, and the persistence of bias | The Great Debate