"IN ORDER TO GET BEYOND RACISM, we must first I take account of race." So wrote the late Justice Harry A. Blackmun in 1978, in one of the six opinions in the Supreme Court’s landmark decision in Regents of University of California v. Bakke. By a 5-4 vote, the Court struck down a rigid racial quota in admissions at a University of California medical school. But one member of the majority, the late Justice Lewis F. Powell, Jr., suggested that he would uphold a more flexible plan using race as a modest plus factor, such as the one then used by Harvard.

Now we have been taking account of race for three decades in admissions to virtually every highly selective university in the nation, as well as in employment and government contracting. The Supreme Court is due to issue by early July its first major decision since Bakke on the constitutionality of racial preferences in state university admissions, in a case brought by disappointed white applicants to the University of Michigan’s undergraduate and law schools. It’s a logical time to take stock. Do the benefits of this type of affirmative action exceed the costs? What do the most relevant empirical data tell us about how it works? How much longer should it continue?

First, let’s be clear about what "taking account of race" actually means in deciding whom to admit. Lawsuits have uncovered a great deal of information that had previously been secret. The weight given to race at the University of Michigan appears to be fairly typical of top universities, but unusually easy to measure because Michigan uses a numerical "selection index" to rank applicants; it almost always admits those with the highest scores. Here is how the process would probably work for two hypothetical applicants from the same Michigan high school: