Almost everyone is familiar with the problem. In the United States, Black and Hispanic people are more likely to be stopped, frisked, arrested, beaten, and shot by the police (National Academies of Sciences, Engineering, and Medicine, 2018).
Less well understood are the reasons for these disparities. One popular explanation is the implicit bias hypothesis, which makes two claims. First, that police officers, as a group, hold nonconscious prejudices against Black people and other minorities. Second, these prejudices, which reside outside of awareness, cause officers to treat Black and Hispanic people less favorably than Whites.
In an attempt to address racial disparities in policing outcomes, many police departments in the U.S. have implemented implicit bias seminars. These trainings are unregulated and largely untested, although three recent studies shed some light on their effectiveness.
Three Studies of Implicit Bias Training
In one study, researchers presented a 4-hour implicit bias training to 85 police officers (63 percent male, 39 percent White) who completed an online survey in the days before the workshop and again immediately after the workshop.
The researchers discovered that most of the officers changed their minds about the value and importance of implicit bias education. They came to believe that bias education was “in their own best interest and [could] improve their relationship with the general public” (Vitriol, Banaji, & Lowe, 2024). Unfortunately, the researchers measured self-reported attitudes only—which may not predict actual behavior.
In another study, researchers measured the impact of a one-day implicit bias training on the knowledge, attitudes, and intentions of 3,764 police officers (Lai & Lisnek, 2023). Officers who completed the training became more knowledgeable and more concerned about racial prejudice; they also became more motivated to address bias in their conduct as police officers. Unfortunately, the effects of the training were short-lived. After one month, concerns about bias and intentions to police in a less biased manner returned to their pre-training level.
In a third study, published last month, researcher Robert Worden, of the University of Albany, and his colleagues investigated the impact of a one-day implicit bias training on the frequency of police stops, arrests, searches, and use of force. The training was delivered to 14,471 police officers (81 percent male, 44 percent White) in New York City.
The training was designed to (1) increase officers’ knowledge of the damaging effects of unconscious prejudice and (2) teach specific techniques that officers can use to manage their own thoughts and behavior. Officers were taught to perform self-checks, avoid profiling, use “slow down” responses, and assess situations thoroughly to reduce ambiguity.
When Worden and his team examined policing outcomes over time, they discovered that the implicit bias training had no impact on racial and ethnic disparities. Before the training, 55 to 60 percent of the police stops in New York City were of Black citizens—and 30 percent were of Hispanics. Those numbers did not change after the training (Worden et al., 2024).
A second pattern was also unaffected by the training—and this is perhaps good news. Although Blacks and Hispanics are more likely to be stopped by the police in New York City, the individuals who had been stopped were not more likely to be frisked, beaten, or shot because of their race or ethnicity. In other words, the racial disparities are confined to police stops. After a suspect has been stopped, police officers do not treat Blacks, Hispanics, and Whites differently, according to this research.
In short, implicit bias training in New York City had no impact on officers’ policing decisions and failed to reduce racial disparities in policing outcomes.
Why Don’t Diversity Training Programs Work?
Careful reviews of the efficacy of anti-racism and implicit bias programs have come to a discouraging conclusion: They appear to have little or no positive long-term effects (Singal, 2023). Why don’t they work?
First, most programs aren’t designed to reduce implicit bias per se; they’re designed to make individuals aware of prejudices they may hold.
Second, mandatory workshops often lead to defensiveness, and what psychologists call “reactance.” When a new rule or policy threatens our autonomy, we’re motivated to reassert our independence by ignoring or even contradicting the rule.
Third, implicit bias is a controversial concept in terms of its definition, measurement, and (in)ability to predict actual behavior. Some behavioral scientists have argued that implicit bias is not a useful scientific concept and should be abandoned. (Explicit bias, on the other hand, is measurable and predicts discriminatory behavior.)
Finally, the racial disparities that exist in police stops, arrests, and use of force may not be a product of racial prejudice. They may exist for reasons that have nothing to do with a police officer’s frame of mind. Studies have found that rates of violent crime are higher in neighborhoods that are economically and socially disadvantaged. These same neighborhoods are more likely to have residents who are Black or Hispanic (Worden et al., 2024).
