In 2002, a team of researchers at the University of Washington decided to take the defenses of the drug war seriously, by subjecting the arguments to empirical testing in a major study of drug-law enforcement in a racially mixed city - Seattle. The study found that, contrary to the prevailing "common sense," the high arrest rates of African Americans in drug-law enforcement could not be explained by rates of offending; nor could they be explained by other standard excuses, such as the ease and efficiency of policing open-air drug markets, citizen complaints, crime rates, or drug-related violence. The study also debunked the assumption that white drug dealers deal indoors, making their criminal activity more difficult to detect.

The authors found that it was untrue stereotypes about crack markets, crack dealers, and crack babies - not facts - that were driving discretionary decision making by the Seattle Police Department. The facts were as follows: Seattle residents were far more likely to report suspected narcotics activity in residences - not outdoors - but police devoted their resources to open-air drug markets and to the one precinct that was least likely to be identified as the site of suspected drug activity in citizen complaints. In fact, although hundreds of outdoor drug transactions were recorded in predominantly white areas of Seattle, police concentrated their drug enforcement efforts in one downtown drug market where the frequency of drug transactions was much lower. In racially mixed open-air drug markets, black dealers were far more likely to be arrested than whites, even though white dealers were present and visible. And the department focused overwhelmingly on crack - the one drug in Seattle more likely to be sold by African Americans - despite the fact that local hospital records indicated that overdose deaths involving heroin were more numerous than all overdose deaths for crack and powder cocaine combined. Local police acknowledged that no significant level of violence was associated with crack in Seattle and that other drugs were causing more hospitalizations, but steadfastly maintained that their deployment decisions were nondiscriminatory.

The study's authors concluded, based on their review and analysis of the empirical evidence, that the Seattle Police Department's decision to focus so heavily on crack, to the near exclusion of other drugs, and to concentrate its efforts on outdoor drug markets in downtown areas rather than drug markets located indoors or in predominantly white communities, reflect "a racialized conception of the drug problem." As the authors put it: "[The Seattle Police Department's] foucs on black and Latino individuals and on the drug most strongly associated with 'blackness' suggest that law enforcement policies and practices are predicated on the assumption that the drug problem is, in fact, a black and Latino one, and that crack, the drug most strongly associated with urban blacks, is 'the worst.' This racialized cultural script about who and what constitutes the drug problem renders illegal drug activity by whites invisible. "White people," the study's author's observed, "are simply not perceived as drug offenders by Seattle police officers.

A survey was conducted in 1995 asking the following question: "Would you close your eyes, envision a drug user, and describe that person to me?" The startling results were published in the Journal of Alcohol and Drug Education. Ninety-five percent of respondents pictured a black drug user, while only 5 percent imagined other racial groups. These results contrasted sharply with the reality of drug crime in America. African Americans constituted only 15 percent of current drug users in 1995, and they constitute roughly the same percentage today. Whites constituted the vast majority of drug users then (and now), but almost no one pictured a white person when asked to imagine what a drug user looks like. The same group of respondents also perceived the typical drug trafficker as black.

There is no reason to believe that the survey results would have been any different if police officers or prosecutors - rather than the general public - had been the respondents. Law enforcement officials, no less than the rest of us, have been exposed to the racially charged political rhetoric and media imagery associated with the drug war. In fact, for nearly three decades news stories regarding virtually all street crime have disproportionately featured African American offenders. One study suggests that the standard crime news "script" is so prevalent and so thoroughly racialized that viewers imagine a black perpetrator even when none exists. In that study, 60 percent of viewers who saw a story with no image falsely recalled seeing one, and 70 percent of those viewers believed the perpetrator to be African American.

Decades of cognitive bias research demonstrates that both unconscious and conscious biases lead to discriminatory actions, even when an individual does not want to discriminate. The quotation commonly attributed to Nietzsche, that "there is no immaculate perception," perfectly captures how cognitive schemas - thought structures - influence what we notice and how the things we notice get interpreted. Studies have shown that racial schemas operate not only as a part of conscious, rational deliberations, but also automatically - without conscious awareness or intent. One study, for example, involved a video game that placed photographs of black and white individuals holding either a gun or other object (such as a wallet, soda can, or cell phone) into various photographic backgrounds. Participants were told to decide as quickly as possible whether to shoot the target. Consistent with earlier studies, participants were more likely to mistake a black target as armed when he was not, and mistake a white target as unarmed, when in fact he was armed. This pattern of discrimination reflected automatic, unconscious thought processes, not careful deliberations.