Like many people, I think the practice of racial profiling—the police or security practice of targeting individuals for investigation because of their race, ethnicity, or national origin—is obviously wrong. What’s less obvious, to me at least, is exactly why it’s wrong.

It’s not that profiling by itself is problematic. But here I’m thinking of the kind of complex profile investigators may come up with by gathering evidence from the scene of a crime, e.g. a murder. Some of that evidence will be purely physical in nature, but there might also be psychological evidence that can provide a clue as to what kind of person could have committed the crime. A good profiler might be able to infer information about the criminal’s personality, motives, skill set, relationship to the victim, and so on. Race could even be an aspect of that profile. For example, statistically speaking, serial killers tend to be white, so if police are investigating a serial killer, it would make sense for them to look for a white person, though, of course, exceptions are always possible.

The difference between these two types of profiling then—one racial profiling, the other, let’s call it complex profiling—suggests a reason to object to the first but not the second. Racial profiling is just too simplistic. By focusing only on a person’s race or ethnicity, police are making sweeping generalizations about a whole set of people without knowing anything else about their behavior or tendencies. And, we might think, these kinds of generalizations, based only on a single factor, are unjust.

That sounds plausible, except I know I that I do sometimes “profile” people based on a single factor, and I don’t think I do so unreasonably or unjustly. That single factor is gender. If I’m walking down the street alone at night, as a woman, I’m naturally going to be much more vigilant of men than I am of other women. I think this is probably true for many men too—they don’t tend to feel threatened by women on the street, but they may be wary of other men. Similarly, when we hear about violent crimes, we automatically assume they’re committed by men and are surprised to hear of a woman who commits such a crime. Think of serial killers again. We tend to assume they’re men and we’d be right to do so!

What’s the difference here? If it’s legitimate to be more wary of someone simply because they’re male, then why not because they’re black, or Latino, or Middle Eastern? It can’t be that focusing on a single factor is the problem, because gender is a single factor. So what is the problem with racial profiling?

The answer, I think, has to do with the predictive power of race. When it comes to violent crime, I think gender is genuinely predictive because of statistical regularities. Race, on the other hand, is not genuinely predictive in the same way.

Defenders of racial profiling might point to the higher population of African Americans or Latinos in prisons as evidence that race is predictive of certain kinds of crime, but I don’t think this kind of claim can stand up to scrutiny.

Take something like marijuana possession. Should the fact that blacks make up the majority of those incarcerated for this non-violent (and arguably victimless) crime lead us to believe that they are more likely to break anti-marijuana laws, or the law in general? This comprehensive report from the ACLU explains exactly why this is such a bad inference. So, why are so many black men incarcerated for a crime that, statistically speaking, they are actually less likely than whites to commit? Because they are more likely to be arrested for marijuana possession than whites. And why is that? Because of racial profiling. Because police are more likely to pull over and search a black driver than a white driver, despite the fact that a higher percentage of blacks have never used marijuana compared to whites.

The problem with racial profiling, then, is that it reflects racist attitudes and reinforces racist institutions. It is a tool of oppression dressed up as a tool of law enforcement.

If that’s the case, then how do we address it? This, I think, is a very difficult question, particularly when we consider some of the recent research on implicit bias, or unconscious prejudice, which shows that often our explicitly held beliefs conflict with our implicit attitudes.

In other words, the cop who pulls over a young black guy who is driving through a rich, white neighborhood because he looks “out of place” may not have explicitly racist beliefs, but he enacts racist attitudes in his unconscious evaluations and responses. He perceives the black man as a threat because of his implicit bias. Even a black cop could have such an implicit bias, just as women may have unconscious prejudicial judgments about other women. We internalize all sorts of negative stereotypes and unconsciously act upon them, even when they conflict with our explicit avowals.

Overcoming these implicit biases becomes more complicated when we consider how, by necessity, so much of how we read other people is done unconsciously. Consciousness is slow and clunky, and it requires a great deal of cognitive resources, which is why so much of our cognition happens automatically, or implicitly. We have all sorts of cognitive mechanisms that operate below our conscious awareness and if we didn’t, we’d never get anything done! We rely on these unconscious mechanisms to navigate our way through the world and to respond with speed and accuracy to what gets thrown in front of us. That includes our responses to other people.

Our show this week explores the issue of racial profiling in the light of this research on implicit bias. How and why do we develop these biases in the first place? Are all racial or ethnic stereotypes harmful? How does the kind of crime that police focus on (e.g. marijuana possession versus insider trading) reflect our racial biases? And what kinds of steps are needed to tackle the problem of racial bias and end racial profiling?