For about four decades, the US has had a system of racial preference (affirmative action) meant to remedy the dire consequences of its previous system of racial preference (Jim Crow). Last Monday, a narrow decision in the Supreme Court showed that the system has reached the limits of its logic.

The Ricci case concerned 118 firefighters who took a promotion test in New Haven, Connecticut, in 2003. The pool was a mix of whites, blacks and Hispanics and none of the 27 black candidates qualified for promotion. So the city threw out the test results. The white and Hispanic firefighters who had qualified sued the city on the grounds that they had been discriminated against. The Supreme Court found they were right. “The city made its employment decision because of race,” Justice Anthony Kennedy wrote. “The city rejected the test results solely because the higher scoring candidates were white.”