How stereotypes influence us, even if we don't accept them

Interesting analysis of the recent Trayvon Martin incident based on psychology studies involving 'the Police Officer's Dilemma' : tests to make split second shoot/don't shoot decisions.
http://blogs.scientificamerican.com/guest-blog/2012/03/26/trayvon-martins-psychological-killer-why-we-see-guns-that-arent-there/?WT_mc_id=SA_WR_20120330
Some points :

• First of all, no matter how racist the participants were (or were not), they were equally likely to shoot unarmed Black targets; outright levels of racism did not predict the results at all. However, one thing did predict performance on the task ? the participants? level of awareness that there is prejudice towards Black people in American society, even if the participant adamantly did not support those stereotypes. Simply being highly aware of prejudice in the world, even if you don?t agree with, support, or like that prejudice, makes it more likely that you might make the fateful mistake of shooting an unarmed target when making split-second decisions in uncertain conditions. The more aware you are of cultural stereotypes, the more likely you are to make a biased mistake.
• Correll?s research demonstrated that everyone ? even an upstanding college undergraduate lacking any racial prejudice ? is vulnerable to making racially biased decisions, particularly under the split-second pressures of the Police Officer?s Dilemma. Did racism motivate George Zimmerman?s actions against Trayvon Martin? Yes. But does a person have to be racist to make the same split-second decision? No.
• When the ?shooting game? task was given to Black participants, they turned out to be just as likely to accidentally shoot unarmed Black targets as the White participants were.
• At the end of the day, it?s not always about whether or not you are racist, or whether or not you think that Black people are violent. Cultural stereotypes can become automatically activated and applied to our behaviors even when we don?t actually endorse them; the sheer knowledge that these stereotypes exist can be enough to influence our judgments, especially when it comes to split-second decisions. Because of cultural stereotypes, the shooters in Correll?s games had a lower threshold for when they would decide it was OK to shoot at Black targets, although most of them probably could not have told you that this was happening, and most of them would have been appalled to find out about their biases.