A Detailed Look at the Downside of California’s Ban on Affirmative Action

Mr. Bleemer’s study does not support the mismatch hypothesis. If Black and Hispanic students had benefited from enrolling in less selective universities, they would have been more successful in rigorous math and science courses there. They were not. Instead, they were less likely to earn bachelor’s degrees in a science or engineering field, as well as less likely to graduate over all, compared with Black and Hispanic students before Proposition 209. They were also less likely to earn graduate degrees.

Any differences in their classroom success compared with white and Asian-American students appeared to be largely explained by lower-quality preparation in K-12 schools, the study said, not admissions preferences. Black and Hispanic students with lower high school grades were affected most. Mr. Mountjoy calls the study “an important and impressive piece of scholarship” that “brings some clarity to this chaotic literature.”

Proposition 209 also depressed the number of highly qualified Black and Hispanic high school students who applied to the University of California system, perhaps because they mistakenly believed they would not be accepted.

The timing could not have been worse. California in the late 1990s was on the cusp of an explosion in technology-created wealth. Degrees from the state’s elite universities were a ticket to the riches of Silicon Valley. Because of Proposition 209, students of color in the study earned 5 percent less on average every year, an effect that persisted into their mid-30s, when the study period ended. The impact on wages was concentrated among Hispanic students, who were also significantly less likely to earn more than $100,000 per year.

Of course, selective university admissions is a zero-sum game. For every Black and Hispanic student excluded by Proposition 209, another student, probably white or Asian-American, took their place. But in focusing on those who got into the most selective U.C. campus at Berkeley, the study found that white and Asian-American students didn’t actually benefit from the policy in concrete ways.

Mr. Bleemer’s study suggests they would have otherwise enrolled in an equally selective college elsewhere, and had the same chances to graduate and begin successful careers.

Another recent study of the Texas top 10 percent admissions preference found similar results: The more racially and economically diverse students who benefited by enrolling at selective University of Texas campuses were more likely to graduate and earn higher salaries, while the students who were displaced did not suffer by the same measures.