He looked at states from 1995 through 2003, a period in which California, Florida, Texas and Washington State banned affirmative action in admissions. He found that in states that eliminated the consideration of race in admissions, black students saw a gain in their exposure to white students (of 1.45 percentage points) and a decrease of the dissimilarity index of 1.66 points. That means, he said, that the result of the bans was not to exclude black students from higher education but to redistribute their enrollment -- and to do so in ways that more closely reflected enrollment patterns in those states.
Hinrichs is quick to say in the paper (and in the interview) that his findings do not suggest that states should ban affirmative action. (Hinrichs said he describes himself as neither a supporter or critic of affirmative action, seeing both benefits and problems with the practice.) He said that there are valid reasons for people to want to assure higher levels of black enrollment at elite institutions than might be the case without affirmative action. But he also wrote that the data show that "it is plausible that an affirmative action ban could decrease measured racial segregation."The abstract:
This paper documents how segregation between blacks and whites across colleges in the United States has evolved since the 1960s. It also explores potential explanations for the trends. The main findings are as follows: (1) White exposure to blacks has been rising since the 1960s, whereas black exposure to whites increased sharply in the late 1960s and early 1970s and has fluctuated since then. Meanwhile, black-white dissimilarity fell sharply in the late 1960s and early 1970s and has fallen more gradually since. (2) There has been regional convergence, although colleges in the South remain more segregated than those in any other region when measured by dissimilarity or by black exposure to whites. (3) A major channel for the decline in segregation, especially in the South, is the declining share of blacks attending historically black colleges and universities. (4) Recent statewide affirmative action bans by some states may actually be reducing racial segregation.