In this game, the player takes on the role of a police officer who is confronted with a series of images of white or black men variously holding guns or innocent objects such as wallets or cellphones. The aim is to shoot anyone with a gun while holstering your weapon in other cases.
Ordinary players (often university undergraduates) routinely shoot more quickly at black men than at white men, and are more likely to mistakenly shoot an unarmed black man than an unarmed white man.
In effect, we have a more impulsive trigger finger when confronted by black men and are more cautious with whites. This is true of black players as well, apparently because they absorb the same cultural values as everyone else: Correll has found no statistically significant difference between the play of blacks and that of whites in the shooting game.
Excerpt taken from “Is Everyone A Little Bit Racist?” by Nicholas Kristof.