He uses a chilling example to highlight how racial profiling can lead to horrific outcomes. In 1999 in the Bronx, a young Black immigrant named Amadou Diallo was standing outside his apartment complex. 4 police officers, in plain clothes, driving an unmarked car, drove by and were supposedly shocked that a man standing outside his own home would be so brazen as to continue standing there, as a car drove by. The 4 cops (all white) decided this was very suspicious behavior, so they got out of the car and approached him, while yelling at him. Diallo became fearful, and retreated to the door, trying to get it open. The police charged. Diallo pulled a black object from his pocket. The cops thought he had a gun. They killed him. Between the four cops, they fired 41 bullets at him. Four cops. Against one retreating man. 41 bullets. After killing him, they finally saw what was really in his hand. A wallet. Amadou Diallo had recently immigrated to the USA and didn't speak English well. He thought they we going to mug him. So he retreated, while trying to give them his wallet. And they killed him, because they deemed him to be a threat, based on biases that completely twisted their perception of reality. 

Gladwell goes on to give an insightful explanation on how biases against Blacks lead to false and very harmful perceptions. 

Thanks Casey! 

heeey whats up casey, and coolio youre added!