Since blacks represent a disproportionate share of those arrested for certain crimes, police believe that it makes sense to stop a disproportionate share of blacks. Carl Williams, Superintendent of the New Jersey State Police, put the matter even more bluntly in an interview with the Newark Star-Ledger. In other words, officers may be targeting blacks and other minorities, but this is a rational thing to do. This type of thinking means that anyone who is African-American is automatically suspect during every drive to work, the store, or a friend's house. Suspicion is not focused on individuals who have committed crimes, but on a whole racial group.
Skin color becomes evidence, and race becomes a proxy for general criminal propensity.
Pretextual traffic stops aggravate years of accumulated feelings of injustice, resulting in deepening distrust and cynicism by African-Americans about police and the entire criminal justice system. But the problem goes deeper. If upstanding citizens are treated like criminals by the police, they will not trust those same officers as investigators of crimes or as witnesses in court. Fewer people will trust the police enough to tell them what they know about criminals in their neighborhoods, and some may not vote to convict the guilty in court when they are jurors. Recent polling data show that not just blacks, but a majority of whites believe that blacks face racism at the hands of police.