I have an oped in the New York Times today discussing an issue that I explore at length in my new book — the problem of colorism. Most people think about racial prejudice as being merely about how whites think about blacks, but the reality is far more complicated and nuanced. The issue is not just that racism is about groups other than whites and blacks. A vast array of experimental studies show that even within a single group, our minds make intricate distinctions between people. Within a group such as African-Americans, for example, our unconscious minds make subtle gradations that cause us to discriminate more against black people who are darker skinned than those who are lighter skinned.

Don’t take my word for it — the oped and the book detail empirical research that proves that darker skinned African-American defendants are more than twice as likely as lighter skinned African-American defendants to receive the death penalty for committing crimes of equivalent seriousness. Colorism, as it is sometimes called is both an inter-racial problem and an intra-racial problem.